Chapter 1,2,7,8,9 Psych 200, Psych 200 Learning and Memory-- Chapters 3,4,5, &6, Psych 200- Exam 1 Video Notes, Learning and Memory

eyewitness testimony (video)

(Jennifer Thompson) 22 year old college student Some man broke into her hour and raped her Two women were raped in the same nightt (Jennifer Thompson) was brought in to do a photo line up (Jennifer Thompson) she said it was ronald cotton (Ronald Cotton) Had a record of breaking and entering and sexual assult (Ronald Cotton) He was sentenced to life plus 50 years -when he walked into the prison kitchen a man that looked like him was in there (Bobby Poole) (Bobby Poole)-Was brought in for rape in a different case. He heard that Bobby Poole had admitted to raping Jennifer and the other women (Ronald Cotton) He was able to get another trial and Bobby Poole was sitting in the front row of this trial (Ronald Cotton) was convicted again for 2 life sentences (Ronald Cotton) after 7 year later the OJ Simpson case was on trial--- he would listen to it on the radio and found out about DNA He asked his new atorny about his DNA They were able to Match DNA from his sperm It was able to come back as bobby poole. (Jennifer Thompson) met ronald after he was let go and asked him to forgive her

3 Major theories:

- James-Lange - Cannon-Bard - Two-factor • James-Lange theory proposes that emotions start with physiological (autonomic) responses, which are then perceived by the CNS to create conscious emotional feelings. - Independently proposed by William James and Carl Lange - Consistent with this theory, merely adopting body postures for an emotion can actually lead to conscious experiences of that emotion (e.g., holding a pen between the teeth, which mimics a smile, can induce increased happiness in human subjects). • Cannon-Bard theory proposes that physiological and conscious components of emotion are actually independent. - Proposed by Walter Cannon, a student of James's, and elaborated by Philip Bard - Notes that physiological arousal does not automatically lead to emotional feelings (e.g., running elevates heart rate but doesn't cause fear) • Two-factor theory synthesizes prior approaches, suggesting that arousal and context are interpreted by the CNS to generate conscious feelings. - Developed by Stanley Schachter and Jerome Singer - Sees emotional feelings as based on interpretation of the situation • Falling sensation -> in a roller coaster, interpreted as safe, feeling of exhilaration • Falling sensation -> crashing elevator, interpreted as unsafe, feeling of fear • Supported by considerable experimental evidence ... • Interpretation of physiological arousal (Schacter & Singer, 1962): - Participants injected with epinephrine, causing increased heart rate and blood pressure - Each participant placed with a colleague instructed to act in a different way: joyful or angry - Participants reported feeling the same emotion as the colleague—they interpreted the physiological effects of the injection to be consistent with their expected outcome.

Axon

is where the electrical signal travels from the dendrite to the axon terminal

The scientific study of learning and memory indicates ways to improve these processes:

-Pay attention -Use imagery -Use multiple senses -Sleep well -Relax -Create associations -Practice -Reduce overload -Try a rhyme -Re-create the learning event

Priming

1) Initial Prime: MOTH SUPREME (on first slide; primed participants only) 2) Complete these stems: MOT__ SUP___ 3) Results:Primed Participants MOTH SUPREME Unprimed Participants MOTEL or MOTER SUPPOSE or SUPPER 1.Prime some participants with initial exposure to stimulus (can be without explicit processing). 2.Re-expose participants to stimulus or partial stimulus. Due to prior exposure, participants more likely to recognize stimulus and faster to process In this example, the initial primes were "MOTH" and "SUPREME", written on the first two slides. -Did you respond "moth supreme"? Priming is a subtle but reliable effect. -Did you remember seeing them? Priming works even without conscious recall. •Priming is also a form of perceptual learning. •Priming has many applications within psychology and in the real world. -Can you think of uses in advertising? -"Psychics" often use priming ... Can you think of how?

Philosophical Traditions: Rules of Association

Aristotle proposed that ideas are built by rules of association: 1.Contiguity - experiences near each other in time/space are joined together 2.Frequency - experiences often repeated are connected more strongly 3.Similarity - experiences similar to one another are connected

A Model of Memory Formation The Atkinson-Shiffrin Model-with some additions (1968)

1.Stimuli are recorded by our senses and held briefly in sensory memory. 2.Some of this information is processed into short-term memory/working memory and encoded through rehearsal . 3.Information then moves into long-term memory where it can be retrieved later. 4.Some information seems to go straight from sensory experience into long-term memory; this is automatic processing.

Jennifer Thompson

22 year old college student Some man broke into her hour and raped her Two women were raped in the same nightt she was brought in to do a photo line up she said it was ronald cotton

Cortical Representations of Sensory Stimuli//Distributed Representations// Generalization and the Hippocampal Region

: •Initial cortical processing of sensory information occurs in areas dedicated to each sense. •Each area exhibits an anatomical mapping of the sense (e.g., homunculus for touch). • This topography occurs via adjacent cells with overlapping receptive fields Distributed Representations: •As experience shapes receptive fields, the topography of the cortex is also reshaped: -Habituation to a tone: contracts cortical space devoted to that pitch -Fear conditioning to a tone: expands cortical space devoted to that pitch •Experience thus distorts cortical maps to emphasize processing of relevant/important stimuli! Generalization and the Hippocampal Region: •The hippocampus plays an important role in learning about relationships between sensory cues. •Specifically, hippocampus damage disrupts performance: -Sensory preconditioning task -Acquired-equivalence tasks -Latent inhibition

Punishment// Making Punishment Effective

A punisher is an outcome that decreases the frequency of the behavior. Punishment or Generalized Suppression? •Skinner noted that during punishment, animals cease many activities, not just the punished one (less appetite, less movement, etc.). •Also, punishment can become less effective with time, with Rs creeping back up to non-punished levels. •Proposed that punishment does not produce true operant conditioning (true learning of a contingency) •Instead produces generalized suppression, a temporary decrease in most behaviors Skinner was wrong!! •Although punishment can produce a general decrease in behavior, the punished behavior decreases much more. •Punishment does not always wear off. This is a problem only with weak punishers, which can cause habituation. •Still, using punishment effectively is very tricky: -Circumvention - animal may learn discriminative stimuli that help it avoid punishment -Can produce fear/anxiety/rage that can impair behavior -Can produce generalized behavior disruptions -Can produce aggression •Therapists disagree over the utility of punishment in therapy and child rearing. Making Punishment Effective: •Manner of Introduction -Weak punishers habituate -Escalating punishers habituate more -Need to start with strongest punishment •Immediacy: •Longer delay between R and S, weaker effect of punishment •Schedule: •FR1 most effective, other VRs much less effective •Alternatives: •Having other Rs greatly improves effectiveness of punishment •Discriminative Stimulus - signals the contingency is in effect •With punishment, discriminative stimuli can enable cheating -e.g., if police are watching, speeding -> fine -e.g., if coach is watching, foul play -> run laps •For effective punishment, contingency should always be in effect.

Adolescence: Childhood to Adulthood

Adolescence: Childhood to Adulthood • Adolescence: the transitional stage between the onset of puberty and full adulthood • Strong development of working memory and central executive function during adolescence. • Digit span increases through early teens. • Executive function develops throughout early adulthood. • Why? • Ongoing development of frontal lobes • Increasing familiarity leading to better encoding: child chess experts can remember more chess pieces than adults, due to higher familiarity • Gender differences also emerge during this time: • Women perform slightly better (on average) on verbal memory and on spatial learning of landmark locations. • Men perform slightly better (on average) on spatial learning of routes. • Similar gender differences evident in many mammals, suggesting the differences aren't purely cultural • Gender differences may be due partly to different levels of sex hormones between males and females (more on this later).

Aging Memory: Adulthood to Old Age

Aging Memory: Adulthood to Old Age • Adult abilities can stay stable for many years. • Unfortunately, though, the overall pattern is decline in most basic memory and learning skills. • Working memory is one of the first to show age-related decline. - Proactive interference? Older adults have learned much more and may be less able to prevent this from interfering with the formation of new memories. • Similar trends for learning: - Eyeblink conditioning starts declining at 40-50 and can take twice as long in older adults relative to young adults. - Skill learning declines rapidly after 60 (e.g., rotary pursuit). • Some good news: strong compensation - Although basic skills decline, older adults have more skills and experience to draw on. - This richer pool of experience can often help compensate for diminished skills and enable performance of complex skills at the same or better level than in young adults! • Example: older typists make slower movements, but have better semantic memory and need to look at their manuscript less often, leading to excellent overall performance. • Warning: use it or lose it! Overall performance is only preserved in skills that are practiced throughout aging. • Semantic and episodic memory show uneven decline. • The ability to retain and retrieve these memories shows little decline during healthy aging. - e.g., Seniors who studied Spanish in high school still recalled many Spanish words learned, even with little practice over long spans of time. • Unfortunately, the ability to form new episodic and semantic memories does decline with age. - Older adults show poor paired associate learning. Deficits can be ameliorated with slower rates of presentation and/or meaningful stimuli.

myelin sheath

Allows the electrical signal to travel faster down the axon so instead of activating every ion channel down the axon only the channels in the spaces between the myelin sheath called the Node of Ranvier is activated and activities of action potential

From STM to Working Memory

Baddeley proposed that STM be re-conceived as working memory Working memory is a workspace for the mind. It collects sensory input, activates relevant LTMs, and transforms information to suit current needs. •Baddeley also decomposed working memory into 3 component parts -Phonological loop - inner voice -Sketchpad - inner eye -Central executive - attention

The Reign of Behaviorism

Behaviorists worked to make psychology more scientific and objective: They focused on objectively observable events: stimuli and responses. They adopted an evolutionary approach. They searched for mathematical laws of behavior that would apply to humans and other animals as well. •Tolman found, though, that the exclusive focus on stimulus and response is too narrow. Key figures include Watson, who named the movement, Hull who focused on mathematical models of learning, and especially Skinner, who became a leading public intellectual

Blocking//Blocking: Why is this strange?

Blocking: •Control group: -Trained to tone+light CS preceding shock US -Afterward, both tone and light produced modest CRs (freezing) •Pre-trained group: -Pre-trained with light CS preceding shock US -Then same tone+light CS training as in the control group -Afterward, light produced large CR and tone produced none Analogy: •Anne, the perfect stock analyst—an amazing find! •Bob, the perfect stock analyst you meet 1 week after Anne—who cares! He's redundant. Blocking: Why is this strange? •Because both groups experience the same association between tone and the shock •However, prior experience with the light+US association blocks learning of the tone+US association •Suggests that CC is about tracking information in the environment •When the CS is redundant to what is known, no learning occurs •Thus, it seems as though internal states (what the organism already knows) are required to explain CC

Autism Spectrum Disorder//Brain Substrates of Social Learning: Issues//Mirror Neurons

Brain Substrates of Social Learning: Issues SAME: Social learning involves memories for both episodes (I saw her do this) and skills (now I'm going to do the same). Perhaps, then, are the brain substrates the same as for traditional episodic and skill memory? DIFFERENT: Strong social learning is only evident is some species. Perhaps, then, it takes specialized brain structures. • How is it done? - Encoding: Visual or auditory observations (what the model did) - Retrieval: Actions or speech (what you do) - How are memories for model actions translated into motor plans? Mirror Neurons • Recordings from awake primates have revealed so-called mirror neurons: neurons that fire for both watching and doing an action. - e.g., A mirror neuron might fire when a monkey grasps an object and when it sees another monkey grasp an object. • Mirror neurons seem to represent a neural component of social memory, linking observed behaviors with motor outputs. - True imitation: Some mirror neurons fire only during specific activities, when observed and performed. - Emulation: Other mirror neurons fire for specific outcomes, regardless of how achieved, when observed and performed. • Humans do seem to have mirror neurons. - Not usually possible to record directly. - However, EEG and fMRI both indicate that some brain regions are activated for both observing and performing action. - Areas of joint activity match those where mirror neurons are found in primate relatives. Song Learning in Birds • As in social learning in mammals, birds exhibit brain activity that seems to help map observations (songs heard) onto performance (songs being sung): - Neurons in two song centers (RA and HVC) are active both when listening to songs and when producing songs. • As with skill learning in mammals, song learning in birds also requires the function of a brain area homologous to the basal ganglia (area X). Socially Transmitted Food Preferences • Learning paradigm: - A demonstrator rat is fed food with a novel odor (e.g., cinnamon-flavor food). - The demonstrator rat is then placed in a cage with a food-deprived observer. - The observer smells the scent of food on the demonstrator's breath, and will form a long-lasting preference for that flavor food. • Lesion studies indicate important roles for the hippocampus and the basal forebrain. - Hippocampal lesions produce retrograde amnesia with a temporal gradient (most recent food preferences are most affected). - Basal forebrain lesions completely eliminate ability to retrieve socially learned food preferences, but new preferences can be formed. - Anatomically, very similar to the brain substrates of episodic memory. Autism Spectrum Disorder • A syndrome defined primarily by impaired social function: - Poor social interactions - Need to have strict routines - Sensory overload - Stereotypical/repetitive movements - Echolalia - repeating words and spoken phrases - Symptoms are quite varied across those afflicted. • Only recognized as a distinctive disorder in the 1940s; definitions and diagnosis are tricky, and under debate. • Autism has been suggested to be a type of "mind blindness"—an inability to understand the mental life of others. - According to this theory, autistics should have great difficulty with true imitation, as they lack the processing necessary for this type of social learning. - The evidence on this is mixed, though... • Autism is associated with some deficits of imitation: - Some studies have shown strong deficits, others less so. - Autistic children can complete do-as-I-do tasks for simple actions (e.g., drinking) but had difficulty with action sequences. - In the two-action task (model demonstrates, then observe to see if specific model behavior is copied), older autistic children tested normally, but younger autistic children were impaired. - Probably not a global deficit of all social learning, but some specific impairments seem common. • Autism has been associated with a wide range of brain abnormalities, but causal links remain unclear: - Sensory cortex - Prefrontal cortex - Hippocampus - Cerebellum - Amygdala - Basal ganglia - Corpus callosum - Temporal lobes - Mirror neuron system? • Diversity of findings may reflect generalized developmental problems, diversity of symptoms, and/or problems of diagnosis! • Imitative Deficits After Stroke • Stroke can also cause problems with imitation and social learning. - Parietal lesions can cause difficulty initiating movement (apraxia) that includes difficulty imitating. - Frontal lobe lesions can cause "involuntary imitations," including echolalia. These make the patient susceptible to disruption ... Come up with a real world example (that is different from the examples we talked about in class today) of each of the following: - Social Learning: Learning in which the learner actively monitors events involving other individuals and then chooses later actions based on their observations. - Emulation: Accomplishing the same overall goal as the model but in a different way - Observational conditioning: When cues in the environment become associated with contagion reactions - Contagion: Inborn tendency to react to cues from other members of the same species - Stimulus enhancement: When a teacher directs the attention of the learner to particular parts of the environment

Clinical Perspectives: Negative Emotions, Stress, and Health

Clinical Perspectives: Negative Emotions, Stress, and Health • Negative emotions and high stress can cause: - Physical problems (e.g., high blood pressure, suppressed immune system) - Psychological problems (anxiety disorders) • Phobia—overwhelming, irrational fear of an object, place, or situation - e.g., ophidiophobia (fear of snakes), agoraphobia (fear of open spaces) - Best explained as arising through classical conditioning procedure Classical Conditioning and Phobias • Stimulus in a phobia is almost always something that was threatening to human ancestors - A biological predisposition to fear certain things • Not everyone who has a fear-evoking experience develops a phobia. - Possibly developed through social transmission (e.g., fear of flying develops after reports of airplane crash)

Clinical Perspectives

Clinical Perspectives: •The hippocampus plays a major role in guiding generalization and discrimination. •Damage to the hippocampus can therefore disrupt these functions. -Alzheimer's -Traumatic brain injury -Stroke -Schizophrenia

Practice: Constant vs. Variable

Constant practice is focused on a single skill. Constant practice: Play the G Major scale 20 times. Variable practice alternates between a set of skills Variable practice: Play the G, C, E, and D Major scales 5 times each. Variable practice is often (but not always) more effective However, constant practice is sometimes as good or better; it is still unclear how to pick the best practice schedule for a specific skill.

Aristole proposed that ideas are built by rules of association

Contiguity Frequency Similarity

Thorndike's Puzzle Box

Cool, but some methodological problems •Have to repeat trials over and over, resetting animal and device •Cutoff? - What is worst performance? •Decreases with learning •Hard to compare across animals, trials •How do you generate a prediction from latencies?

Copying What Is Seen

Copying What Is Seen The experimental study of social learning started with a set of experiments by Albert Bandura. Wanted to see if aggressive behavior in adults would be copied by children. • Exposure: - Children watched an adult modeling aggressive behavior (beating on an inflatable Bobo doll) or an adult modeling quiet play. • Test: - Children were watched while playing with toys, including the Bobo doll. Some children were provoked by taking away their first toy of choice Bandura found a complex pattern of results: • For children provoked, those who had viewed adult aggression were more likely to be aggressive. - Often copied specific actions and words from the adult, demonstrating clear use of the adult as a model • For children unprovoked, those who had viewed adult aggression were less likely to be aggressive themselves. • Despite their complexity, clear demonstration that just observing adult behavior influences child behavior • Moreover, the ability to learn from observation seems to reflect complex cognitive operations, including perspective taking. • Note that these points do not align with behaviorism ... The experimental study of social learning started with a set of experiments by Albert Bandura. Wanted to see if aggressive behavior in adults would be copied by children. • Exposure: - Children watched an adult modeling aggressive behavior (beating on an inflatable Bobo doll) or an adult modeling quiet play. • Test: - Children were watched while playing with toys, including the Bobo doll. Some children were provoked by taking away their first toy of choice Bandura found a complex pattern of results: • For children provoked, those who had viewed adult aggression were more likely to be aggressive. - Often copied specific actions and words from the adult, demonstrating clear use of the adult as a model • For children unprovoked, those who had viewed adult aggression were less likely to be aggressive themselves. • Despite their complexity, clear demonstration that just observing adult behavior influences child behavior • Moreover, the ability to learn from observation seems to reflect complex cognitive operations, including perspective taking. • Note that these points do not align with behaviorism ...

Basal Ganglia and Skill Learning: Review

Declarative and procedural memories are distinct in terms of behavior and brain mechanisms: Declarative memory (semantic and episodic):Flexible, consciously accessible, verbal Consolidation depends on the medial temporal lobes (MTL), especially the hippocampus. HM and others with bilateral MTL damage can no longer form new declarative memories, but can learn new skills. Procedural/Skill memory -Rigid, not always consciously accessible, hard to verbalize -Depends on the basal ganglia, cerebellum, and regions of cortex -Parkinson's patients and others with basal ganglia damage are impaired at skill learning, but fine with forming new declarative memories.

Multiple Memory Systems

Declarative memories can be broken down into two types: •Episodic - memories for specific autobiographical events (e.g., first kiss) •Semantic - memories for facts and general knowledge (e.g., your mother's name) •Both are forms of declarative memory. •HM could not form new episodic and semantic memories, though he could recall those he had formed before surgery. What type of memory? •Remembering how you got to class today Episodic •Remembering your address Semantic

Medial Temporal Lobes and Memory.. Depth of Processing+ False Memory

Depth of Processing: Deeper processing may involve more MTL activity, producing better encoding. -Images produce bilateral MTL activation; words only unilateral. -More MTL activity during learning predicts not only ability to recall but also the ability to remember source information. False Memory: In the related word paradigm, the hippocampus is "fooled" by the lure word (the word that is related but not presented). -One region of MTL, though, is only activated by the words seen, not the lure word, suggesting a possible physical way of distinguishing true from false memories! •Taken together, strong evidence that the MTL (especially the hippocampus) consolidates declarative memories. •But how, exactly, does this work? •Two current theories, though no clear answer yet: -Standard consolidation theory -Multiple memory trace theory •Standard consolidation theory: -During learning, the MTL relays information to the cortex. -Over time, however, the cortex gets the message and the memories become independent of the MTL. •Explains why brain disruption usually damages recent memories (still undergoing consolidation) but not older memories (fully consolidated) •Multiple Memory Trace Theory: -The MTL helps organize together the distributed semantic facts into specific episodic memories. -True episodic memories are never fully independent of the MTL. •Explains cases of severe retrograde amnesia. Also suggests that spared memories after MTL damage are actually semantic rather than true episodic.

Philosophical Traditions: Descarte

Descartes' dualism: immaterial soul + mechanical body Mechanical side: Our bodily similarity to machines and non-human animals Immaterial soul: Our ability to think and freely make decisions The mechanical aspect was a radical step, and opened the way for scientific, mechanistic investigation of human behavior.

An inside look at Young Onset Parkinson's Disease (YOPD)---Martin Parker

Diagnosed with Parkinsons disease for 2 years now On alot of medication to help with every day life (4) help them with his movements and freezing Purpose--not to feel sorry for him just want to show how he is on his meds , off his meds and importance of research and development -he still works be a good father being a good husband - what he can do -- everything you take for granted, putting on your shirt, getting out of bed, walking -speech and choppy -going to work usually takes and hour to kick in - movements arent perfect -buttoning his shirt - able to do it completely -left hand is really effected -right hand isnt to bad Next day---- freezing up his body cant walk on one feet left arm is a little slow feels like his bones are punchering his skin and cant stop pushing against something Buttoning his shirt (off drugs) - bearly can put it on, isnt smooth, having a hard time, leaning against the wall, needs help buttoning sleeve, having a hard time walking foot is curled medication is helping his foot, isnt dragging his limbs and is able to move his hands

Assessing Emotion in Nonhuman Animals

Do nonhuman animals feel emotions? • We can't ask, but often observe behaviors that seem consistent with deep-felt emotions... - A dog's joy when its owner returns - Elephant burials - Still, it is impossible to say if these behaviors are accompanied by conscious feelings. • Evolutionary considerations suggest yes, as we are unlikely to be different from our animal relatives in such a qualitative way. - Darwin noted that fear behaviors are very similar across many mammalian species. - Similarities include startle, piloerection (hair standing on end), possible loss of bladder control, release of cortisol, increased heart rate, pupil dilation, and more. - Some of these behaviors seem conserved across much of the animal kingdom. - Still, these similarities in behavior don't necessarily indicate similarities in conscious experience ... • Neuroethology also suggests similarities in emotions, even for positive emotions such as joy. - Panskepp et al. have developed extensive evidence that rats laugh and feel joy. - During play, rats turn one another over and nuzzle each other's bellies (tickling?) causing the emission of ultrasonic squeals (laughing?). - Rats prefer to be with rats that tickle and laugh frequently and will avoid those who do so infrequently. - Panskepp's results may also generalize to other mammals. • Although fascinating, most lab research on emotion has focused on fear, as it is very easy to induce and measure.

Before Behaviorism

Dominant School of Psychology Primarily Freudian psychoanalysis, saw human behavior as primarily irrational and driven by subconscious forces Methods Dream analysis, introspection, authority, debate Subjects Only humans, as we are unique mentally Human Motivation Our behavior is driven by subconscious drives Impact Ridiculed by many of the "hard" sciences for a lack of objectivity, infighting among analysts, perceived lack of progress

Down Syndrome//Animal Models of Down Syndrome//Alzheimer's Disease

Down Syndrome Down syndrome—congenital form of intellectual disability, which occurs equally in girls and boys • Retarded speech and language development; low IQ scores • Usually caused by trisomy 21 (extra copy of a chromosome 21) - During embryo formation, parent's (usually mother's) chromosome fails to split properly. Brain Abnormalities and Memory Impairments • In Down syndrome, brain size may be average at birth, but growth in some areas (e.g., hippocampus, frontal cortex, cerebellum) may be stunted. • Individuals tend to have profound deficits in hippocampal-dependent memory abilities. - Young adults with Down syndrome performed at the 5-year-old level on mental abilities tasks. - This suggests that the hippocampus is an area of special impairment for adults with Down syndrome. Animal Models of Down Syndrome • Mice bred for segmental trisomy (Ts65Dn mice) showed deficits in hippocampal-dependent tasks (e.g., location of maze goal). • Enriched environment improved spatial memory in female Ts65Dn mice. - Exacerbates impairment in Ts65Dn males Alzheimer's Disease Alzheimer's disease (AD)—a form of progressive cognitive decline from accumulating brain deterioration • AD affects about 5.3 million people in the U.S. - As many as 1/3 of people over age 85 are afflicted. • AD progression: - Earliest symptoms of AD occur in episodic memory, such as forgetting recent visitors. - Later, there are declines in semantic memory (e.g., forgetting familiar names, locations). - Next, conditioning and skill memory deteriorate. - In late-stage AD, there is often a lack of awareness and daily living skills. Plaques and Tangles In the Brain Amyloid plaques = deposits of beta-amyloid (abnormal byproduct of amyloid precursor protein, or APP; kills adjacent neurons) • Plaques are fairly evenly distributed across cerebral cortex Neurofibrillary tangles = collapsed protein scaffolding within neurons • Early in AD, accumulate in hippocampus and MTL, relating to semantic and episodic memory deficits • Hippocampal shrinkage = early AD warning sign • Verification of presence of plaques and tangles (to confirm AD diagnosis) can only happen at autopsy. • 10% of "probable AD" diagnoses (based on MRI, PET, lumbar puncture, etc.) are incorrect. • Many other conditions (some treatable) mimic AD, so better diagnostic tests are needed. • e.g., vitamin B deficiency, hypothyroidism, depression Genetic Basis of Alzheimer's Disease • Several genes implicated in AD • Most progress understanding genetic cause of early-onset AD (begins at 35-50 years) - Less than 1% of AD cases = early-onset - Caused by genetic mutations, which are autosomal dominant (meaning, just 1 mutated gene from either parent will trigger early-onset AD) Connection Between Down Syndrome and Alzheimer's Disease? • Chromosome 21 (implicated in Down syndrome) contains APP (implicated in AD). • By age 35-40, adults with Down syndrome develop neural plaques and tangles. • Half of Down syndrome patients show memory decline and other symptoms of AD; other half do NOT show cognitive decline. - Why? Unclear. Explanation will help in understanding both pathologies.

How does it all work?

Dual-process theory:••Perceptual learning occurs due to decreased responding to common stimulus features, allowing only unique/unusual features to control behavior. Comparator model: ••Repeated exposure to a stimulus allows construction of a mental representation of the stimulus; responses are only to degree of mismatch between external stimuli and internal representations. Differentiation model:••Each exposure allows additional small set of stimulus details to be learned, slowly building more precise representations of external stimuli. ••Similar to comparator model, but more generalized and less focused on habituation.

Emotion, Storage, and Retrieval

Emotion, Storage, and Retrieval • Very emotional events can lead to particularly vivid episodic memories: flashbulb memories - 9/11 - JFK Assassination - Challenger Disaster - Any that you have for national or personal events? • Flashbulb memories suggest that emotion can greatly increase memory encoding. • But is this true? Are flashbulb memories really very accurate, or do we just feel that they are? • Flashbulb memories are not perfectly accurate, as memory-researcher Ulrich Neisser realized about one of his own: • More detailed studies show that memories for highly emotional events (such as 9/11) do decay over time, and are prone to misattribution errors (such as other episodic memories). • Still, evidence does suggest that emotion can boost memory encoding... • Participants were told a story about a hospital visit: - As part of a drill (non-emotional) - As part of an accident (emotional) - Both stories had the same beginning and end, and varied only in the middle segment. • Participants were told a story about a hospital visit: - As part of a drill (non-emotional) - As part of an accident (emotional) - Both stories had the same beginning and end, and varied only in the middle segment. - The emotional component of the story was remembered much better. • Emotion can also influence retrieval: mood congruence increases recall • Recalling memory in the same mood as encoding fosters recall. • Another application of transfer-appropriate processing. (Remember the scuba divers?) • Unfortunately, emotions have a complex relationship with the brain: - A single emotion activates many different brain regions. - The same brain region can be activated by the more than one emotion. - Despite this complexity, the amygdala stands out as a structure involved in many types of emotional processing ... • The Amygdala: An Emotion Processing Station • Name means "the almond" in Greek • Collection of many different nuclei, only some of which are shown here (many have little/no role in emotional processing) • Collects emotionally relevant information from cortex and thalamus • Coordinates behavioral and physiological expression of emotion • Modulates brain centers related to memory and learning • Amygdala: A collection of subcortical nuclei in the anterior temporal lobe • The central nucleus of the amygdala organizes the expression of emotional responses: • Stimulation can cause species-typical defensive responses (e.g., in rabbits: freezing and lowered heart rate). • Stimulation in humans can cause positive or negative emotions, and can also cause outbursts of rage (Delgado, 1971). • Disruption leads to impairments of emotional learning in humans and other animals ... • The central amygdala is required for fear-conditioning: - CS (a colored shape) paired with blast of noise (US) - In normal and hippocampal patients, CS comes to evoke a strong skin-conductance response (SCR), due to emotional arousal. - In patients with bilateral amygdala damage, the US is effective, but the association with the CS is never learned (left). - Similar results are observed in rats with lesions to the central nucleus (right). • The lateral amygdala provides inputs, and thus may play a particularly important role in emotional learning ... - The lateral amygdala collects inputs and seems to encode emotional relevance of stimuli: - Fast and rough input direct from the thalamus : gets to amygdala quickly, but minimal processing doesn't allow for fine distinctions between stimuli - Slow but accurate input from the cortex: gets to amygdala more slowly, but inputs are more accurate - Emotional learning refines neural responses in the lateral amygdala ... • Animals pre-tested on two neutral odors (left) • One odor (almond) then paired with foot shock • Activity of neurons in the lateral nucleus recorded before and after training • Selective increase in activity to trained odor, suggesting encoding of emotional relevance of the stimuli • The basolateral amygdala may modulate memory to increase storage of emotional memories. - Imaging studies show that emotional events activate the amygdala. - Degree of amygdala activation predicts memory boost for emotional material. - Amygdala activation also correlates with stronger feelings of "knowing" emotional material, both at encoding and recall. • Emotional stimuli cause the release of stress hormones. • This is monitored in the basolateral nucleus, through a relay in the brain stem that releases epinephrine. Strong activation of this pathway predicts better encoding. • Altering epinephrine alters this feedback pathway and the effects of emotion on memory... • Enhancing epinephrine boosts emotional memory. • Rats given a foot shock (left) upon entering a chamber hesitate before re-entering. • Boosting epinephrine just after training (right) increases hesitation. • Similarly, blocking epinephrine decreases the boost in recall for emotional stories. • Recap of proposed amygdala functions in emotion: - The central nucleus of the amygdala organizes the expression of emotional responses. - The lateral amygdala collects inputs and seems to encode emotional relevance of stimuli. - The basolateral amygdala may modulate memory to increase storage of emotional memories. • Still considerable debate over what these areas do: - Does the amygdala store fear memories, or just organize the activity of other brain regions? - Answer is still not clear

What Is Emotion?

Emotions have three related facets: - Physiological responses (e.g., changes in heart rate, respiration, etc.) - Overt behaviors (e.g., smiling, baring teeth, etc.) - Conscious feelings (e.g., the actual feeling of the emotion) • Example: fear response: - Heart rate increases, pupils dilate, color drains from face - Startle responses (e.g., jumping) - Internal feeling of fear, anxiety, fright • Ekman has suggested that 6 basic emotions are innate to humans (though modifiable by culture): Happiness, surprise, fear, sadness, anger, and disgust

Encoding Emotional Context: Hippocampus

Encoding Emotional Context: Hippocampus • In fear conditioning, animals learn not only the pairing between CS and US (tone and shock) but also the context of the relationship. After training, simple re-exposure to the context (training chamber) also evokes fear responses. • Although the hippocampal lesions have no effect on fear conditioning of the CS-US relationship, it abolishes contextual learning: training apparatus no longer provokes fear responses. Feelings and the Frontal Lobes The frontal cortex also plays important roles in emotional processing: Mood regulation: frontal lobe damage can cause changes in emotional regulation, with some patients exhibiting flattened mood and others experiencing heightened and inappropriate emotionality. Social cues related to mood: Frontal lobe damage can impair the ability to recognize facial expressions of mood. fMRI studies show enhanced activation of the medial PFC while viewing emotional faces Fear learning: • Frontal lobe damage can impair extinction of fear responses, leading to perseveration of the response.

False memory

False memory: Most participants remember the omitted word (e.g., rain). False confidence: ••Moreover, most are very confident of the memory. False detail: ••Most scary of all, many will report specific details about the false memory. ••Position in the list ••In one experiment, words were read by alternating male and female voices; each participant "remembered" the voice that had read the omitted word. Memory is malleable; this is of special concernfor eyewitness memory in criminal justice system

Stimulus Generalization Model Using Discrete-Component Representations//Generalization Gradient Produced by Discrete-Component Network

Generalization Gradient Produced by Discrete-Component Network: *Shows no response to yellow-orange light (despite similarity to previously trained yellow light). Only responds to trained "yellow" stimulus; fails to show a smooth generalization gradient like that shown in Fig 6.3.

Genetic Basis of Learning and Memory//The Developing Brain

Genetic Basis of Learning and Memory Selective breeding experiments also demonstrate genetic influences on learning and memory. • Rats tested trained on a maze, then tested for memory. Number of errors recorded (Tyron, 1940): - "Maze-bright": rats making less errors than average - "Maze-dull": rats making more errors than average • Selective breeding: maze-brights mated with other maze-brights and maze-dulls with maze-dulls • Over several generations, genetic effects clear. Works in other lab animals, too. • Twin studies also demonstrate genetic influences on learning and memory. Procedure: - Identify identical twins, fraternal twins, and siblings - Test basic learning and memory skills and determine if genetic similarity is related to similarity in test results Results: - Genetic similarity predicts similarity of learning and memory skills (identical twins most similar, fraternal twins moderately similar, siblings less similar) - Estimated that as much as 50% of variation in learning and memory may be related to genetics (though studies tend to select participants with roughly similar backgrounds) - Strong genetic influence, but equally strong influence of environment... The Developing Brain • Human brain development is strongly influenced by the environment. • Specifically, human brain development features competition between cells and synapses; survival seems based on usefulness: - Overproduction - Competition for a limiting resource related - Winnowing to select most useful cells and synapses • This competition is similar to natural selection, but operates to sculpt brain development for maximal utility within the organism's environment. • Competitive brain development is found mostly in mammals, most other animals show more programmatic development. The Developing Brain: Competing Neurons • Neurons are produced very rapidly after conception (up to 250,000 per minute). • Production is mostly complete by 25 weeks (though connections between neurons are not as established). • More neurons are produced than needed, and competition ensues: • Rules of the competition are not completely clear, but seem to be based on access to limited resources, such as BDNF. • Success in obtaining these resources seems related to success in making useful synaptic contacts and relaying useful information. • Unsuccessful neurons undergo apoptosis (programmed cell death), which may cull up to 1/3 of the neurons initially produced. • This competition between cells enables environmental demands to drive the wiring of the brain! • Competition within neurons as well ... The Developing Brain: Competing Synapses • Synaptic connections start around 5 months and are made at rates of 40 k per second! • More synapses are produced than needed, and competition ensues within each neuron: - Competition seems based primarily on usage, favoring connections with strong pre- and post-synaptic activity. - Unsuccessful synapses are broken and materials recycled, claiming up to 42% of all initial connections. • Competition and synaptic remodeling continues throughout life, though pace and scale of change decreases, especially in the sensory cortex. • Overall, competition between cells and within cells produces environment-driven brain development. This extends brain development, though, long after birth ... Brain Changes in Adolescence Adolescence corresponds to changes throughout the brain, but especially in the frontal cortex. Synaptic • changes strong synaptogenesis in frontal cortex though 11-15 years of age, pruning throughout early adulthood Myelination • Cortical axons are wrapped in myelin, improving speed and fidelity of communication between brain areas. Starts after birth, not complete until around 18 years, especially in the frontal cortex Modulation • dramatic increase in dopamine inputs from the midbrain to the frontal cortex during adolescence • Adolescence is also when most sex differences fully emerge (though many begin even before birth). • On average, male brains weigh a bit more and contain 4 billion more neurons (~4% difference). • Some specific brain regions are larger in men (blue). Others are larger in women (red), including the hippocampus. • These brain differences may relate to the subtle behavioral differences in some learning and memory tasks. The Brain from Adulthood to Old Age • Unfortunately, aging is associated with brain deterioration: - Decrease neuronal density - Decreased synaptic density - Overall loss of brain matter, up to 5% of total weight by age 80 • Some loss may be due to neurodegenerative disease (e.g., Alzheimer's) and/or mini-strokes, but even in healthy aging, substantial loss of neurons and synapses is apparent. • Loss is uneven across brain areas and correlates with skill decline. - Frontal cortex shows substantial loss, as does working memory. - In monkeys, degree of decrease in frontal lobe neuron density relates to decreased working memory performance. • Even where neuron and synaptic numbers are stable, wiring may become less stable and functional ... The Brain from Adulthood to Old Age Barnes and colleagues examined synaptic stability over age. • Procedure: - Place cells in rat hippocampus were mapped during exploration of a maze. - Rats were returned to the same maze at a later date, and place cells remapped. Results: • For young rats, same place cells encoded same places within the maze (top panel). • For older rats, same place cells active in different areas of the maze (bottom panel). Old rats retained some level of behavioral performance in the maze. They had less stability in the place cells Adult Neurogenesis? • It was once thought that all neurons were produced before birth (with a good portion then competed into apoptosis). • Recent evidence, however, suggests limited neurogenesis in adult mammals, including humans. - Injection of radioactive BrdU into brains, which was incorporated into neurons undergoing cell division - Brain harvested at a later date and checked for radioactive cells. These were created after the injection. • Some limitations: - Only in specific brain regions (e.g., hippocampus) - Relatively small number (1-2 thousand/day) - Up to 99% of new neurons die! (not sure why) - Functional role not clear yet, though learning increases neurogenesis in adult hippocampus.

Retrieval: Transfer-Appropriate Processing

Godden and Baddely, 1975 Procedure: ¨Participants learned 2 lists of 40 words One list learned on land One list learned underwater (during SCUBA) Subjects then tested Same context: land list tested on land, scuba list on scuba Different context: land list tested on scuba, scuba list on land Results: Same context group performed significantly better. Interpretation: Retrieval works best when conditions are similar to encoding conditions. Study tip: Study the way you'll be tested (question format, etc.).

sensitization vs habituation

Habituation- Decreased behavior innocuous stimulus repeated exposures stimulus specific Sensitization- Increased behavior Noxious stimulus single trail (more helps) Generalization

What is going on in there?

Habituation: a decrease in the strength or occurrence of a behavior due to repeated exposure to the stimulus that produces the behavior How does the brain of the rat rewire so that the same stimulus will now produce a different behavior? Difficult to answer with many billions of neurons in the brain ...

outside the neurons

Higher concentration of sodium ions

Frontal Cortex Damage

Humans with frontal cortex damage often have dysexecutive syndrome, a decrease in working memory and executive function. This causes problems both in real life and during psychiatric evaluation. Real Life: Wilder Penfield's sister, who had frontal lobe damage due to tumor removal. Formerly an accomplished chef, became aimless in the kitchen, moving haphazardly between tasks. Elliot, a successful accountant who also suffered frontal lobe damage due to surgery. Became unreliable, couldn't maintain relationships, went bankrupt. Easily swayed by whims; couldn't stick to plans.

Plato

Proposed that we are born with innate differences in skill and talent and suggested sorting by quality soon after birth

Working Memory, Cognitive Control, and Intelligence

Intelligence: capacity to learn, reason, and understand •What, specifically, is it that makes someone intelligent? •One possibility: excellent working memory function -Working memory correlates with verbal SAT scores. -Being able to juggle many rules in one's head is correlated with scoring high on non-verbal tests of intelligence. -General intelligence is associated with a stronger working memory, especially the control and manipulation of larger numbers of rules, concepts, goals, and ideas.

Little Albert

John Watson and Rosalie Rayner (his graduate student) tested the conditioned response of fear in a 9-month old boy named "Little Albert" Watson prided himself in his ability to shape people's emotions. He later went into advertising. In the infamous Little Albert experiments, Little Albert was exposed to a white rat. He was unafraid of the rat. Then, Albert was exposed to a white rat followed by a painfully loud gong sound, a startling stimulus that immediately caused Baby Albert to cry. After several pairings of the rat and the gong, Baby Albert began to whimper and cry when exposed to the rat. •What is the US->UR reflex in this scenario? •What is the CS->CR reflex in this scenario? •Which changes during training? How? •What would you do to treat Baby Albert's new fear of rats? • •Come up with two more examples of conditioned responses, tell me what all of the components are (US, UR, CS, CR). Neutral Stimulus: The white rat Unconditioned Stimulus: The loud noise Unconditioned Response: Fear Conditioned Stimulus: The white rat Conditioned Response: Fear

Man-Machine Interfaces

Just as sensory prostheses can help people to overcome deficits in perceptual abilities, electromechanical devices called motor prostheses can help people to recover lost abilities to learn and perform perceptual-motor skills.

learning and memory

Learning: the process by which changes in behavior arise as the result of experience interacting with the world Memory: the record of our past experiences which are acquired through learning

Memory Development: Infancy to Childhood

Memory Development: Infancy to Childhood • Understanding the development of learning and memory: - Helps tailor school and teaching to place appropriate demands on students - Helps us understand normal brain development and opens possibilities for extending/improving function across the life span • One caveat: - Developmental trends represent averages across considerable variability. - Variability exists within a cohort (e.g., the huge diversity of ACT scores for high school seniors). - Variability also exists across developmental trajectories. • Incredibly, the ability to learn is intact even before birth. • By 34-36 weeks, auditory habituation: - A speaker is placed on the mother's abdomen. - Sounds initially cause fetal movement. - Repeated sounds decrease responses. • Prenatal preferences can be formed and persist after birth: - Mothers read specific books twice a day for last 6 weeks of gestation. - 2 days after birth, babies given an opportunity to work to hear the familiar story or a novel story: • Long pause in sucking -> familiar; short pause in sucking -> novel story • (for half the babies, the opposite contingency) - Regardless of the contingency, babies adapted sucking rates to gain exposure to the familiar story! • Some limitations are evident due to immature sensory and motor systems. • Formal experiments show excellent classical and instrumental conditioning... • Infant instrumental conditioning: kick leg -> move mobile • Quickly leads to vigorous leg kicking • Memory maintained for days (no reminders) to weeks (with reminders) • Discriminant stimuli: • Trained in crib with striped crib liner • Kicking in striped cribs • No kicking in plain cribs • Infants also show classical conditioning (remember Little Albert?). • Basics intact from birth, some aspects mature: - Eye-blink conditioning slower in infants than adults - Trace conditioning (gap between CS and US) not possible until age 4, and even then still a bit slower than adults • What about complex forms of learning, such as social learning? • How about infant memory systems? - Infants have semantic memory, which develops further over time. - The development of episodic memory is less clear. - Let's look at each of these in turn ... • Infants have semantic memory, which develops further over time. • Elicited imitation paradigm: - 10-month-old children shown a) how to operate a toy puppet or b) the puppet alone (no demonstration) - Four months later, presented with same puppet - Children who had seen the puppet demonstrated were later more interested in it and were better able to use it. - Shows intact recognition for puppet and how to operate it! • Just like in non-verbal animals, very young children can display memory for what happened where and when, even if they cannot yet verbalize those memories well. Sensitive Periods for Early Learning • Some learning abilities are only available early in life, a so-called sensitive period or critical period after which some forms of learning may become difficult/impossible. • Imprinting: forming a close bond with first individual seen after birth - Common in birds, but also occurs in otherspecies - Bond forms best immediately after birth; after this critical period harder to form • Sensitive periods are also evident in other systems: - Visual development: impaired visual input early in development leads to permanent disruption of visual system. - Male sparrows raised in isolation don't develop normal songs, unless played tape recordings during the exact right developmental time frame (30-100 days after birth). • Human language has also been suggested to have a sensitive period. Let's take a closer look... Some evidence suggests language must be learned before ~12 years of age to be fully mastered. • Despite extensive tutoring, "feral children" fail to develop normal language (e.g., Genie). • Skill at phonetic discriminations is lost during development for sound distinctions not used in exposed languages. On the other hand ... - Adults can actually learn a second language more quickly than young children, though they don't usually end up with the same level of mastery. - Differences in mastery may be more related to time-on-task, which young children have lots of relative to most adults.

Memory Failure: Interference+ Memory Failure: False Memory

Memory Failure: Interference •Similar/overlapping information can interfere with memory, producing storage and retrieval errors. •Proactive interference: old information interferes with new information -e.g., keep using old phone number even though you've moved •Retroactive interference: new information interferes with old information -e.g., after you've finally learned the new number, hard to remember the old one you once knew so well Memory Failure: False Memory •Loftus and colleagues have shown that memories can be modified and manipulated after encoding. •Example: -Wade et al. photoshopped kids into photos of events they had never really participated in. -After viewing the photos, most kids claimed the event had really happened and "remembered" details not contained in the photos. •Participants shown a list of words all related to a specific topic, but the topic itself is not on the list •wet, umbrella, puddle, mud, clouds, fog, falling, drops, galoshes •Note: Rain is not included. •Later tested for recall...

Current approaches?

Most modern researches acknowleges that are shaped by both nature vs nurtue Still disagreement over relative importance in different (eg. IQ and personality)

Philosophical Traditions: Nature vs. Nurture

Nativist: humans are shaped primarily by their biological inheritance (nature).--Fixed at birth; born great (or not) Empiricist: humans are shaped primarily by their experience (nurture).--Endless possibilities with the right experiences Nativist: humans are shaped primarily by their biological inheritance (nature).--Some supporters of nativism: -Plato: proposed that we are born with innate differences in skill and talent, and suggested sorting by quality soon after birth -Descartes: proposed that most of our knowledge is innate, not from experience Empiricist: humans are shaped primarily by their experience (nurture).--Some supporters of empiricism: -Aristotle: proposed that knowledge and talent are matters of training and experience, not inheritance -Locke: we are born as blank slates (tabula rasa), completely equal and without innate knowledge. All our habits and skills are due to experience. Current approaches? -Most modern researchers acknowledge that we are shaped by both nature and nurture. -Still, disagreements over relative importance in different domains (e.g., IQ, Personality).

Negative Patterning: When the Whole Means Something Different From the Parts

Negative Patterning: When the Whole Means Something Different From the Parts: •Combinations of stimuli can have very different meaning than when encountered on their own. -Mom at home? Eat dinner in the kitchen. -Dad at home? Eat dinner in the kitchen. -Both Mom and Dad at home? Don't eat dinner in the kitchen (eat in the dining room). •How do we process such complex cues? Negative patterning paradigm has been used to address this question in the lab •Negative patterning task responses to individual cues are rewarded, but when cues are presented together (the pattern), responses must be withheld. -Tone -> Air Puff Light -> Air Puff -Tone + Light -> No air puff •Negative patterning requires extensive training. -Initial response learned to both individual cues and pattern. -Then, gradually, the negative response to the pattern is learned. •Can learning models account for this? -Back to issues of representation •Single-layer network models using discrete-component representations cannot learn negative patterning. •The same is true for simple distributed representations (1 layer). •Seems to require something more •Configural nodes represent combinations of stimuli; require a second "layer" of model. -"tone + light" node will fire only if both inputs are active. •Models with configural nodes can accomplish negative patterning.

Neuropsych evaluation:

Neuropsych evaluation: •Decreased digit span •Poor memory updating: N-back and self-ordered memory test •Poor planning: Tower of Hanoi (shifting disks back and forth aimlessly, not making progress) •Poor task switching, with perseverance: Wisconsin card sorting (learn 1 rule, unable to switch to new rule) •Poor overall IQ: WWI vets with frontal lobe damage had lowest overall cognitive function •In animal models, lesions to the prefrontal cortex produce similar disruptions of short-term memory: -Jacobsen (1936) lesioned PFC in monkeys -Impaired performance on visual memory task •Subsequent work has shown that the lateral PFC seems to be most involved in working memory and executive function ...

Operant vs. Classical Conditioning

Operant: Animal operates on the environment Stimulus evokes a response to produce an outcome (S->R->O) Animal connects context, behavior, and outcome Classical Conditioning: Environment operates on the animal Stimulus evokes response (S->R) Animal learns CS predicts US Operant Conditioning-- •Reinforcers -Person & Context-dependent -Positive Reinforcement - strengthen response by following it with a pleasing stimulus -Negative Reinforcement - strengthen response by removing something undesirable Operant Conditioning in the Skinner Box: Skinner box: a mini universe •Outcomes (O): -+/- food delivery (reward) -+/- shock through wires in the floor (punishment) •Behavior (R): rate of lever pressing Context (S): light that signals box is 'on' Note that animal is 'free' in the chamber, no experimenter intervention (free-operant learning) Also, many possible contingencies can be introduced ...

The scientific study of learning and memory indicates ways to improve these processes

Paying attention Use imagery Use multiple senses sleep well relax create associations practice reduce overload try a rhyme re-create the learning event

Peak Shifts in Generalization

Peak Shifts in Generalization: Discrimination training not only narrows a concentration gradient—it can also shift it, changing the range of generalization. Spence argued that the peak shift arises through the combination of excitatory and inhibitory stimulus-generalization gradients that are established around S+ and S-, respectively. The net association is presumed to be the sum of these gradients, calculated by subtracting the level of inhibition from the level of excitation at each point along the stimulus domain. The peak shift is the movement between the previous maximal responding to S+ at the right vertical line to the new point of maximal responding at the left vertical line.

Aristole

Proposed that knowledge and talent are matters of training and experience not inheritance

Reinforcement and Punishment

Positive reinforcement ••Press lever (R) -> Get food Positive Punishment ••Press lever (R) -> Get shocked Negative Reinforcement ••Press lever (R) -> End shock Negative Punishment ••Press lever (R) -> Food stops Initially tries many things. Eventually, accidentally presses the lever, produces a positive effect---- Now starts hanging around the lever, accidentally presses it again--- Rat has learned a contingency: If light on (S), pressing lever (R) -> food (O). Spends much of its day pressing and eating

Posttraumatic Stress Disorder

Posttraumatic Stress Disorder (PTSD)—Obsessive thoughts, nightmares, or flashbacks persist long after exposure to the traumatic event. - Trigger = many different stimuli reminiscent of original trauma - Individuals with PTSD fail to extinguish normal fear response. - May involve overactive stress hormones - Physiologically: - Cortisol levels remain low and persistent. - Epinephrine may increase without corresponding cortisol release, so fear response lasts longer - Possible drug treatment: - Drugs like propranolol interfere with epinephrine, reducing stress reaction - With administration, the patient may be less likely to develop PTSD. - How to identify individuals at risk for PTSD? - MRI studies indicate individuals with PTSD typically have smaller hippocampal volumes.

Altered Processing as Well

Repeated stimulus exposure does more than alter reflex responses; it also changes your ability to detect and perceive the stimulus. Such altered familiarity with the stimulus has several manifestations: Perceptual learning: repeated experiences with a set of stimuli improve ability to distinguish those stimuli. Can occur with directed training (discrimination training) or by mere exposure. Novel object recognition/ familiarity: altered response to stimuli that have been previously encountered. Priming: when exposure to a stimulus biases future behavior, often without conscious processing of the stimulus. You've effortlessly learned many similar things: Coke vs. Pepsi, McDonald's fries vs. Wendy's, etc. Language! Subtly different sounds with very different meanings.

Schizophrenia (The Divided Mind):

Schizophrenia (The Divided Mind): Symptoms are diverse, but include: -Hallucinations -Delusions -Flattened affect -Social impairment •Neural mechanisms are not well understood, but schizophrenia has been linked to disruption of many different brain functions. •One of the most consistent findings is that schizophrenics and their close relatives show hippocampal shape abnormalities (bottom set).

Schizophrenia and Transfer Generalization

Schizophrenics also show deficits in other tasks that rely on using learned associations across new contexts, or in relationship with other associations. In this task, participants navigate a cartoon character, Kilroy, though a sequence of four rooms by learning to choose the unlocked door from three colored doors in each room. The location of each of the colored doors moves around, and it is color, not location, that is the cue to be learned. In the transfer generalization phase, the decision-making context is manipulated so that in a given room, a door whose color was correct in another room is not the same color in the new room, and is not the correct door in the new room. Compared with controls, patients diagnosed with schizophrenia were markedly impaired at the transfer generalization of the previously learned rules to rooms with different alternative options.

Brain Substrates: The Cerebral Cortex and Semantic Memory

Semantic memories seem to be stored in a distributed fashion throughout the cerebral cortex. Sensory cortex - first cortical processing center for a sense Association cortex - links across senses •Semantic memories seem to be stored in a distributed fashion throughout the cerebral cortex. -Penfield found that cortical stimulation can evoke simple sensations and complex memories. -Recordings from the human cortex show neurons tuned to specific semantic categories. •This neuron from the right hippocampus of an awake human fires to pictures of Steve Carell but not to photos of other celebrities. -Different groups of neurons with complex receptive fields are found throughout the cortex. •Taken together, this evidence suggests that semantic memories are stored across many specialized processing centers in the cortex. •For example, your semantic memory of an apple may involve visual components in visual cortex, olfactory components in olfactory lobe, associations with other fruits in associative cortex, etc.

Brain Substrates: Frontal Lobe and Working Memory

Sensory Store--Working Memory---to either ---Declarative( Explicit) Long term Memory --or to--Nondeclarative (Implicit) Long-Term Memory •The prefrontal cortex is thought to play a prominent role in working memory function. -Brain anatomy -Psychiatric patients -Physiology

The Power of Operant Conditioning

Shaping and chaining provide incredible power to operant conditioning. Shaping •Shaping through successive approximation builds a complex R incrementally. •Initially, contingency is introduced for simple behavior, R •As rate of R improves, contingency is moved to a more complex version of R •Gradually builds a complex R animal would never spontaneously produce Chaining Chaining builds complex R sequences by linking together S->R->O conditions. Initially, train animal to pick up object Next, reward for picking up and then throwing it Allows series of behaviors (as opposed to shaping, which simply elaborates on a single response) •Shaping and chaining can be used together to train animals to complete incredibly complex behaviors. •Both techniques require skill and patience from the trainer. -Keep animal motivated and interested -Select proper training sequence-can't move too fast Both of these techniques are for positive reinforcement. What about punishment?

Similar Stimuli Can Predict Similar Consequences

Similar Stimuli Can Predict Similar Consequences: First, pigeons learned to peck a yellow light (training S) for food. Next, they were presented with novel lights of different colors. Rate of responding was recorded for training and test colors. (Guttman and Kalish study) •Generalization gradient—graph showing how physical changes in stimuli correspond to behavioral response changes •Note how responding is highest for physically similar stimuli but falls gradually away for less similar stimuli. Represents a default balance between generalization and discrimination -Very similar stimuli treated similarly to training light: generalization -Very dissimilar stimuli treated as completely different: discrimination -As we'll see, this default balance can be modified by experience—animals can change the specificity/generality balance based on feedback.

Social Learning: Controversy

Social Learning: Controversy • Bandura's results challenge behaviorist approaches in at least two ways: - Strong learning in the absence of any specific reinforcement (self-motivated learning) - Apparent need for complex cognitive processing (couldn't be understood in simple S-R terms) • Since Bandura, there has been intense effort to ensure that both these points are really true: - Isn't it possible that what seems like social learning is just a form of instrumental or classical conditioning? - Isn't it possible that actions could be copied without complex cognitive operations? - These debates have led to fine distinctions between true imitation (self-motivated and cognitively demanding) and other forms of behavioral change ... Social Learning: More Than One Way True Imitation: Copying specific actions learned from another • e.g., not just hitting Bobo but hitting it the same way the adult did and yelling the same phrases • Demonstrates that the learner has encoded the specific actions of the model and selected those precise memories to guide their ongoing behavior. Without a doubt, cognitively complex. • Behaviorists and others have pointed out, however, that what may seem like true imitation may actually be more simple forms of learning that are compatible with their theories of learning: • Emulation • Observational conditioning • Contagion • Stimulus enhancement • Let's look at each of these in turn ... Social Learning: More Than One Way to Skin a Cat Emulation: Accomplishing the same overall goal as the model but in a different way • e.g., A child might puncture Bobo, which is aggressive, but not in the exact same way as the adult modeled. • Although fascinating, psychologically ambiguous. The learner could have just wanted to achieve the same end and learned their own way of accomplishing it. Doesn't demonstrate full cognitive representation of the model. • Contagion: Inborn tendency to react to cues from other members of the same species • e.g., A friend yawns, and then you do too. • e.g., Someone throws up, and you may too! • Not really learning, and definitely not true imitation. • Just a complex reflex. Doesn't require complex cognitive operations. • Observational Conditioning: When cues in the environment become associated with reactions • e.g., A naïve monkey sees a snake. Other monkeys, who have experienced snakes, freak out. The naïve monkey freaks out too, due to contagion. The snake now becomes linked to freaking out, so on the next sight of the snake, the monkey now freaks out. • This allows social transmission of learned associations, but it fits all the basic principles of classical conditioning. • Moreover, no complex cognitive processing is required. (Monkey doesn't need to understand why the other monkeys are afraid; it simply reacts to their fear and associates this with stimuli around at the time.) • This form of learning can really seem like true imitation, but clever experimental design can show that it does not involve any complex cognition ... • Observational conditioning is "dumb," not cognitively complex: • "Model" blackbird has learned to attack a stuffed owl, which preys on blackbirds. • A naïve blackbird observes attack behavior from the model, but is shown only a plastic bottle, not the owl. Contagion sparks its attack behavior, but it pairs it with whatever stimulus is around, in this case the bottle. • The naïve blackbird learns to attack the bottle! • Obviously, not true imitation, just a complex form of classical conditioning. • Stimulus Enhancement: When a teacher directs the attention of the learner to particular parts of the environment • e.g., Parents point out wet floor and tell child to take care. The child may then be faster to learn that when the floor is wet, running will cause falls. • The learner still undergoes traditional instrumental or classical conditioning; the stimulus enhancement just makes associations more salient (e.g., highlighting a discriminative stimulus). • Again, doesn't require complex cognitive operations • True Imitation: Copying specific actions learned from another. Cognitively complex; challenges behaviorism. • Cheap knock-offs: Ways of learning that can seem like true imitation, but are actually simple and compatible with behaviorism: • Emulation • Observational conditioning • Contagion • Stimulus enhancement • Question: Does true imitation really occur? If so, in what species? • Sorry, behaviorists: True imitation does occur, at least in humans, some other primates, and dolphins. • This can be in two-action tests and with "do-as-I-do" tasks. • Let's look at each in turn...

Social Transmission of Information

Social Transmission of Information • Social transmission of information: A process in which an observer learns something through experiences involving other agents - e.g., If you see someone lose his or her money at a soda machine, you probably won't try that machine yourself. • Social transmission of information is ubiquitous in human society (TV, Internet, books, college classes). • Experiments also demonstrate social transmission in other species, including rats ... • Social transmission of information can lead to social conformity, a tendency to adopt the behaviors of the group. - Enables adaptive behaviors to spread rapidly through a set of conspecifics (e.g., this cheese is a good food source) - Similar to blocking effects, though, social conformity can also impair learning of novel solutions ... • Social conformity can block learning of novel solutions. Procedure: - Demonstrator guppies trained to swim to one of two open holes in a net to escape an aversive stimulus - Naïve guppies then tested with the presence of the demonstrators and an additional, better escape route Results: - Naïve fish tended to follow the demonstrators to the less optimalopening. - Decreasing the number of demonstrators deceased conformity. - Note: this also occurs without social conformity: demonstrators also stick with their initial escape route. - How does social learning and transmission inform our use of media? - Violent movies and video games - Sexualized behavior in the media - Images of health and beauty ... - Centerwall (1992) found that TV ownership in the U.S. increased in tandem with homicide rates (no change in South Africa, where TV was banned). - Many countries introduced TV without a corresponding increase in homicide (e.g., Japan, France). - Correlation does not imply causation! - What about experiments on media exposure? - Children exposed to videos of aggression often behave more aggressively when provoked. - e.g., 7-9 year old boys who already scored high in aggression were more likely to assault other boys during a hockey game after watching a violent video (Josephson, 1987). - Unfortunately, - Most of this research examines only short-term changes. - Relatively little research into possible positive benefits (e.g., deciding to become a medic after watching a war movie). - Still controversial whether or not there is a true causal relationship. - The National Institute of Mental Health, though, cautions that repeated exposure to media violence may decrease sensitivity and increase aggressive behavior. - What do you think? How can the issue be resolved?

Social Learning (aka Observational Learning)—

Social learning is learning in which the learner actively monitors events involving other individuals and then chooses later actions based on their observations. - Informally, often called copying or imitating - Powerful form of learning in humans: - Learn from watching others, watching video, reading books, etc. - Difficult to study, especially in non-humans: - Usually, no reward/punishment specifically given during training - Depends on the learner's attention to and perception of the situation they observe - Up to the learner to decide when/how actually perform behaviors that have been observed - Hard to predict and measure what is learned Does it exist in nonhuman animals? - Some dolphins can learn from both other dolphins and humans. - Some primates can learn to imitate other primates. - It seems, however, that the human species is the only one that makes extensive use of social learning.

Studies of True Imitation

Studies of True Imitation Two-action test detects true imitation and is passed by young humans and chimps. Procedure: - Adult human models opened a box by a) poking pins out of its latch or b) twisting and pulling the pins out of the latch. - Next, young chimps and humans observedto see if they would copy the precisestyle of opening. Results • Human children precisely copied the actions of the human model they observed, demonstrating true imitation. • Young chimps exhibited a mix of true imitation and emulation. • Interestingly, adult humans also show a mix of imitation and emulation. • Young humans and chimps can exhibit true imitation in this two-action test (though chimps less so than humans). • In other two-action tests, as least some imitation in birds and rodents as well—indicating true cognitive representation of their models Do-as-I-do task: • Animals trained on a "do this" command, where reward is given only if the animal repeats the next behavior of the trainer • e.g., Trainer signs "do this," then claps her hands; monkey must clap hands to get reward. • First, animal is trained on the concept of "do this" by using a standard set of actions. • Next, trainer demonstrates a novel action, never before rewarded. • Results: • Two chimps could complete 30 novel actions (Custance, Whiten, & Bard, 1995). • Dolphins can also learn this game. • Indicates an ability to cognitively represent the model's arbitrary actions and repeat them! Definitely beyond the bounds of behaviorism. Copying What Is Heard Vocal learning: Learning to produce particular sound patterns • Again, there are many ways for an animal to learn to produce a particular sound: - Instrumental conditioning: trial and error - Innate/fixed sound patterns (the "ribbit" of a frog) - True vocal imitation - listening to sounds in the environment and trying specifically to copy them; a form of true social learning • Vocal imitation is rare in the animal kingdom: - Seems to be limited: humans, some birds, some marine mammals - This is a rather strange set of species, with only distant relationships. - Especially strange is that our close primate relatives show no ability to imitate sounds. Even traditional operant conditioning produces very limited ability to train specific sounds. - It may be, though, that most animals lack the physical structures necessary to control vocalization with the precision required for true imitation. • Songbirds, however, provide an excellent system for studying vocal imitation as a form of vocal learning ... • Songbirds learn socially: - If raised in isolation, correct singing doesn't develop. - Song dialects are based on region of the species. - Cross-fostering can lead to adoption of foster parent song style, but only if the chick interacts with the parent. • Template model: - Memorize songs similar to genetic template - Refine own production to template - Learn when/why to sing

Wisconsin Card Sorting Test

Subject sorts card according to rules based on different visual dimensions (color in the same stack, shape( star shapped, triangles), number one object on it and 2 in the next pile) Rule is periodically changed by the examiner without warning only by feedback on each trial Sensitive to frontal dysfunction

Systematic Desensitization

Systematic Desensitization—therapy for phobias; present successive approximations of CS while patient stays relaxed - Eventually CS no longer elicits reaction - Procedure: - Phobic person learns to relax on cue (progressive relaxation) - Present anxiety hierarchy—least fearful to most fearful contact with phobic object or event. - Apply hierarchy sequentially while the phobic person remains relaxed; apply step gradually. - Procedure can be slow but is generally successful and long-lasting.

The Challenge of Incorporating Similarity into Learning Models

The Challenge of Incorporating Similarity into Learning Models: The Challenge of Incorporating Similarity into Learning Models Ways of representing stimuli: Discrete-component representation: ••Each individual stimulus is represented by its own node or "component." ••Apple represented by its own nodes Distributed representation: ••Each stimulus is represented by overlapping sets of nodes or stimulus elements. ••Apple represented by: red + round + crispy nodes Distributed representation + configural nodes: ••Distributed nodes plus additional nodes to represent all possible conjunctions of nodes ••Apple represented by: red + round + crispy + (red+round+ crispy) nodes Multi-layer distributed representation: ••Distributed nodes with multiple, flexible layers that can represent both basic and conjunctive properties •Discrete-component representation—each individual stimulus is represented by its own node or "component." -Apple represented by its own nodes •This is the simplest representation scheme, but it is completely unable to account for generalization. -Each stimulus is represented individually, so there is no way to represent relationships between them. -Learning in these models proceeds on a stimulus-by-stimulus basis, with no carryover to other stimuli. -Although wonderfully simple, these types of models are just too simple to account for generalization. -Shortcomings with this approach helped lead to models using distributed representations.

Embodied Emotion:

The role of the autonomic nervous system The physiological arousal felt during various emotions is orchestrated by the sympathetic nervous system, which triggers activity and changes in various organs. Later, the parasympathetic division calms down the body.

Experimental Psychology:

Three innovators bridged between philosophical and scientific approaches to learning and memory: Ebbinghaus: self-study of savings on learning nonsense words Pavlov: laws of association with classical conditioning in dogs Thorndike: law of effect as cats learn to solve a puzzle Key advances not only in understanding learning but in studying learning and memory: •Experimental approach: manipulate an independent variable and observe a dependent variable •Quantitative: put observations on a numerical scale (e.g., % savings) •Evolutionary approach: based on similarity of species, non-human animals can be studied to understand humans; inspiration from natural selection in understanding learning

Retrieving Existing Memories

Transfer is the generalization of a skill from one context to another: -A baseball player trying to play softball -A baseball player trying to play cricket •In general, skills don't transfer well; this is known as transfer specificity: -Experts in chess can be lousy at cards, backgammon, etc. -A concert pianist can be a lousy dancer. •Some transfer does occur, though: -Training drills for a sport usually help with actually playing the sport. -Learning to write with your dominant hand actually transfers (a bit) to writing with your feet (often to the point where your signature can be recognized)! How can we account for the finicky nature of skill transfer? •Thorndike (1901) proposed the identical elements theory: -Training and new context will share at least some elements. -The more shared (identical) elements, the better skills will transfer. -For example: Baseball to softball will transfer better than baseball to cricket. •Conceptually, this is similar to the notion of transfer-appropriate processing for declarative memories. •The main problem with this approach is an independent way of specifying similarity that doesn't rely on degree of transfer.

change blindness

Two diffrnet men Your brain is doing what its suppose to be doing when there is minor changes to the world around us, we often dont pick up on them --Inattentional blindness is the failure to notice something thats fully obvious right there in front of your atterntion is engages on something or someone else --Change Blindness is a failuare to notice a difference between whats there right now and what was there a moment ago. Perceptive and unperceptive humans actually are. We are aware of everthing taking in details Experiment-- asks passerbys for directions for the skyline and then someone takes his place most people didnt notice the change- only tried it 9 times 7/15 didnt either you pay attention to one thing than the other. Age height or color of their shirt Goal isnt to build a photograph or complete model of the world in your mind but it is to make sense of the meaning of the world around you Limitations can help us adapt and compensate for them allowing us to do things that prevent the really negative consequences that can happen due to failures of awareness.

Skill Memories Are Often Formed Unconsciously

We can learn with or without conscious effort. Explicit learning--••learning with conscious effort: ••e.g., studying for an exam Implicit learning--••learning without conscious effort: ••e.g., Have you ever realized that you know the words to a popular radio song, even though you never really tried to learn the lyrics? ••e.g., Can you remember the logo for Target, GAP, or another retailer? Did you consciously work to learn these images or did you learn them implicitly?

Building the S-R-O Association// Timing//

What determines the effectiveness of operant conditioning? Timing from behavior to consequence--- Relationship between behavior and consequence (schedule) Timing: Closer in time behavior and consequence, better the learning Outcomes Can Be + or - : The outcome determines the change in behavior. Positive Reinforcement If it leads to positive effects, do it more. Study-> A good grade Study more. Positive Punishment If it leads to negative effects, do it less. Arrive late -> Points off Arrive late less often. Negative Reinforcement (escape) If it ends/avoids a negative effect, do it more. Take aspirin -> Headache ends Take aspirin for pain more often. Negative Punishment (omission) If it ends/avoids a positive effect, do it less. Curse at ref -> Ejected from game Curse at refs less often.

Stereotypes, Discrimination, and Racism

When our behavior toward another person is based on his or her membership in a category defined by race, ethnicity, national origin, gender, religion, or age, we are implicitly making a generalization on the basis of a stereotype, a set of beliefs about the attributes of the members of a group. How do we learn stereotypes about other people? •Many stereotypes are socially communicated through our parent, friends, and secondhand reports in books, movies, TV, and the Internet, all of which vary greatly in their accuracy. •In the process of acquiring stereotypes, people filter what they attend to through the personal lens of their own needs and self-interest. How should we evaluate the accuracy of a stereotype? •Certain features of a stereotype may be common to many of the members associated with the stereotype but not to all of them. •A category or generalization's value is based on its ability to help us make inductive inferences. •People are more likely to develop categories when features they can easily perceive are predictive of other variables of interest to us. How do we distinguish between appropriate and inappropriate uses of stereotypes? •Using stereotypes appropriately requires finding a balance between specificity (knowing how narrowly a given stereotype applies) and generality (knowing how broadly it applies). •There are two common ways in which a statistically accurate generalization about other people can be misused: -Assume that all members of a category must inflexibly conform to the generalization. -Faulty inverse reasoning. How can we balance the value and risks associated with using stereotypes? •The trouble with stereotypes arises principally when people use generalizations about a group to justify discrimination against individuals, denying the possibility that the generalization may not pertain to everyone in the group. •Prejudicial behavior occurs when a statistical generalization is applied over-rigidly to an individual or otherwise misused. •It would be overgeneralizing about generalizing to conclude that all forms of pre-judging about groups of other people are inappropriate. •Generalization and categorization, including about other people, are fundamental tools for our survival.

Inside the extracellular space

a higher concentration of potassium ions

action potential

a neural impulse; a brief electrical charge that travels down an axon

empirical

actually collected data

Hyperpolarization

change in a cell's membrane potential that makes it more negative. It is the opposite of a depolarization. It inhibits action potentials by increasing the stimulus required to move the membrane potential to the action potential threshold.

Depolarization

change within a cell, during which the cell undergoes a shift in electric charge distribution, resulting in less negative charge inside the cell.

myelinated

covered with myelin sheath

contiguity

experiences near each other in time/space are joined together

Frequency

experiences often repeated are connected strongly

similarity

experiences similar to one another are connected

Quantitative

expressed observations numerically

Nativists

humans are shaped primarily by their bological inheritance (nature) Fixed at birth; born great (or not)

Empiricist

humans are shaped primarily by their experience (nurture). endless possibilities with the right experiences

Descartes Dualism

immaterial soul + mechanical body

Experimental

manipulated an independent variable to observe the outcome on a dependent variable

immortal soul

our ability to think and freely make decisions

Mechanical side

our bodily similarity to machines and nonhuman animals

Descaretes

proposed that most of our knowledge is innate not from experience

sodium-potassium pump

regulates the environment by pumping out 3 sodium ions in exchange for 2 potassium ions

Repolarization

the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential which has changed the membrane potential to a positive value.

natrual selection

the notion that heritable traits that provide reproductive advantages become more common in a population, leading over time to changes in existing species and even the evolution of new species

Learning

the process by which changes in behavior arise as the result of experience interacting with the world

Memory

the record of our past experiences which are acquired through memory

Evolution

the theory that species can change over time, and that all existing species are descendants of common ancestors. •This idea was proposed by Erasmus Darwin (1731-1802) as the study of the natural world revealed similarities between distinct species of animals.

ion channels

they are closed when the cell is in its resting states. the neuron is able to create an action potential b/c of the concentration diffrence of ions between the intracellular space and the extracellular space.

Assoiationism

was further elaborated by other empiricist thinkers including: Aristole, John Locke, and William James

Locke

we are born as blank slates (tabula rasa) completely equal and without innate knowledge. All our habits and skills are due to experience.

Operant Conditioning: Which reinforcements produce more "responding" (more target behavior)?/// Effectiveness of the ratio schedules of Reinforcement in Operant Conditioning

§Fixed interval: slow, unsustained responding If I'm only paid for my Saturday work, I'm not going to work as hard on the other days. §Variable interval: slow, consistent responding I never know which day my lottery number will pay off, I better play every day. Effectiveness of the ratio schedules of Reinforcement in Operant Conditioning: §Fixed ratio: high rate of responding Buy two drinks, get one free? I'll buy a lot of them! §Variable ratio: high, consistent responding, even if reinforcement stops (resists extinction) If the slot machine sometimes pays, I'll pull the lever as many times as possible because it may pay this time!

Mnemonics: Help us move information from STM to LTM

§Read: plane, cigar, due, shall, candy, vague, pizza, seem, fire, pencil §Which words might be easier to remember? §Write down the words you can recall. §Lesson: we encode better with the help of images. A mnemonic is a memory "trick" that connects information to existing memory strengths such as imagery or structure. Helps us to retain the information longer

Moving things from Sensory Memory to Short Term Memory

§We have to pay attention for things to transfer from Sensory to Short Term Memory §Why are credit card numbers broken into groups of four digits? Four "chunks" are easier to encode (memorize) and recall than 16 individual digits. à Memorize: ACPCVSSUVROFLNBAQ XIDKKFCFBIANA §Chunking: organizing data into manageable units XID KKF CFB IAN AAC PCV S SU VRO FNB AQ •Chunking works even better if we can assemble information into meaningful groups: X IDK KFC FBI BA NAACP CVS SUV ROFL NBA Q

Learning Emotional Responses

• Conditioned fear is the most popular paradigm for studying emotion. - A neutral stimulus (CS, usually a tone) is paired with a painful stimulus (US, usually a foot shock). - The CS comes to evoke fear response (CR), including freezing and elevated blood pressure. - Learned quickly, hard to extinguish, occurs over much of the animal kingdom • Another popular paradigm is conditioned escape: - Negative reinforcement paradigm: if R -> take away ongoing noxious S - e.g., press lever to terminate ongoing foot shock - e.g., swim to platform to terminate being in cold water - Also learned quickly and hard to extinguish Conditioned Avoidance Shuttle Box - 2 compartments separated by a barrier, electric floors Light turns out in 1 compartment Floor is electrified Animal can jump over barrier to eliminate shock When lights out: If jump, shock ends Conditioned avoidance is a variation on conditioned escape. In this case, the response can be made before the onset of the noxious stimulation, avoiding its application altogether. Usually conducted in a shuttle box... • Two-Factor Theory: No extinction occurs because light becomes a CS • Cognitive Theory: No extinction occurs because no expectations have been challenged Learned Helplessness Seligman and colleagues found that prior experience can alter avoidance learning: learned helplessness Learned helplessness: Inescapable adverse events impair later avoidance learning. • Animal exposed to several unavoidable shocks • Then given chance to perform avoidance learning • Very low rate of avoidance—animal gives up and stops trying to escape • Generalization: Research has shown that learned helplessness can carry over to many tasks, impairing learning, decreasing effort, and dampening mood. • Inoculation: Early success at controlling averse stimuli diminishes the negative impact of inescapable aversive experiences.

Working Memory

• Stores about 2 s of auditory information Rehearsal is primarily directed at this component. Seems to literally be a "hearing" in the mind: Word-length effect: less capacity to memorize lists of multi-syllable words compared to single-syllable words Those who speak faster can rehearse longer lists of words. Holds both visual and spatial information for manipulation Limited capacity, but capacity is independent from phonological loop (filling one doesn't impact the other) Well studied in non-humans because it is experimentally tractable The working part of your mind; monitors and manipulates working memory buffers Exerts cognitive control over behavior; providing complex organization in response to environmental demands The most important component of working memory, but also the least understood

Timing

•"Backwards" conditioning: US then CS, no learning! •Delay conditioning (top): best learning •Trace conditioning (bottom): optimal interstimulus interval (ISI) with less learning at delays too short or too long •Overall, timing is an important factor in classical conditioning.

HM - Landmark Case Study

•1953: 27-year-old Henry Molaison (HM) has surgery to treat severe epilepsy •Medial temporal lobes were removed on both sides. •Fewer seizures, but at a terrible cost ... Anterograde Amnesia: Couldn't form new lasting memories After surgery, met a new doctor; completed hours of testing with him; the next day, didn't recognize the doctor. After surgery, told favorite uncle had died. Was extremely sad and upset, but the next day, didn't remember that it had happened. HM Symptoms Still intact: •Most of his memories before the surgery: -his parent's names, his childhood home, etc. •Could remember new things as long as he wasworking/attending to the information: -Given a new phone number, could remember it as long as he repeated it over and over; at firstinterruption, number forgotten -Could watch a TV show and follow the plot, but at first commercial completely forgot the earlier part of the show HM - Memory Systems--•HM was the first to show that memory depended on specific and localized structures (medial temporal lobe) rather than a function of the brain as a whole. -Could still work with new information: intact working memory system -Could still remember life before surgery: intact long-term memory system -Without medial temporal lobes, could not transfer from working to long-term memory: impaired consolidation process •Psychologist Brenda Milner discovered that HM could form some types of lasting memories: -Procedures: Learned to trace objects while looking in a mirror -Skills: Learned to play backgammon -All this was done without conscious awareness: HM did not recall learning these things, and would amaze himself with his own skill. •Suggests there are two types of long-term memory: GO TO CHAPTER 7 SLIDE 7

Which Is First, Episodic or Semantic?

•Episodic may develop only after sufficient semantic memories are formed. -Can't remember a graduation ceremony if you don't know what graduation is •Or, semantic may develop from repeated episodic. -Encounter same information in multiple contexts -Specific episodes blend together to form a strong semantic memory •Or, both systems depend on each other.

Episodic Memory in Nonhumans

•Episodic memory is even more difficult to assess non-verbally. •Tulving has argued that episodic memories require a conscious sense of self that animals simply lack. •Careful testing, though, suggests other animals may have something like episodic memory: -Gorillas can learn to use signs to communicate about specific life events (the food given by a specific trainer at a specific time). -Scrub jays ...

What is habituation?

•A decrease in the strength or occurrence of a behavior due to repeated exposure to the stimulus that produces the behavior •Example: Acoustic Startle Response: SEE CHAPTER 3 SLIDE 4-8 Behaviorist approach: focusing on behavior allows objective, standardized measurements (e.g., force of startle) Habituation: Quantification •Note early strong responses, declining to later weak responses •Asymptote - relatively stable point after substantial training Characteristics of Habituation Dis-habituation: •A novel/arousing stimulus can temporarily recover responses to the habituating stimulus. •This fades quickly, though. Stimulus Specificity: •Generally, responses only decrease to the habituating stimulus. •For very similar stimuli, however, there can be some generalization. Spontaneous Recovery: •When repeated stimulus stops, behavior gradually returns to normal. •Time for recovery depends on several factors ... Massed vs. Spaced: •Taking breaks between sessions of repeated stimuli makes habituation develop more slowly but last much longer (works better for studying, too). Weaker Stimulus = More Habituation: •The stronger the stimulus, the less habituation develops. •This ensures that weak/useless stimuli are ignored, but painful/important stimuli gain more attention. •With very strong (noxious) stimuli, sensitization occurs

Features of Skill Memories

•A skill is an ability to perform a task that has been honed through learning. -Reading -Kissing Other examples? •Skill memory is also known as (aka procedural memory) and shares some characteristics with declarative memory (episodic and semantic): -Improves with practice -Can become long-lasting •Skill memories are distinct, though, from declarative memories: -Often hard to verbalize -Can be learned and retrieved without conscious awareness -Always requires repetition for good learning Distinct brain substrates (case of HM) Two different long-term memory systems: •Procedural memory - for skills •Declarative memory - for facts (semantic) and life history (episodic) Like declarative, procedural memories come in different types •Operant responses •Perceptual-motor skills: learned movement patterns guided by sensory inputs -Examples: how to hit a curve ball, how to spike in volleyball -Can be closed or open skills: closed skills are rote sets of movements; open skills require adjustments based on the environment. •Cognitive skills: habits of problem solving -Examples: Tower of Hanoi, reading •Although these categories can be helpful: -Most skills involve both cognitive and perceptual-motor components (e.g., writing). -Learning for both types of skills seems similar. -Psychologists studying cognitive skills often use tasks that participants can learn relatively quickly, such as simple puzzles like the Tower of Hanoi.

Chapter 2 3/3 of lecture

•Accidental brain lesions in humans (and intentional in animals) have revealed how brain regions function and contribute to learning and memory. •Researchers can use implanted electrodes to stimulate neurons and then observe sensations or responses. •Drugs are chemicals that alter the biochemical functioning of the body and affect neural activity by interfering with synaptic transmission. •The ability of synapses to change with experience is called synaptic plasticity. •LTP occurs when synaptic transmission becomes more effective as a result of strong electrical stimulation of neurons. •LTD occurs when synaptic transmission becomes less effective after neurons do not fire together.

Similarity and Learning Models

•Animals readily generalize from the past to the present, with generalization occurring as a function of similarity. •Capturing this ability in a learning model requires thinking deeply about how animals represent the stimuli around them. •As we've seen, distributed representations seem to capture basic generalization. In a while we'll discuss how additional findings require elaboration to distributed representations. When Similar Stimuli Predict Different Outcomes: •Although we initially tend to generalize from past experience to similar stimuli, additional experience can teach us to be more discriminating. •Example: -Gooseberries look like green grapes. If you are allergic to gooseberries, you learn to distinguish them from green grapes (discrimination). This type of learning takes feedback ... •Discrimination Training-providing two different consequences for stimuli initially treated by an animal as similar -S (1,000 Hz tone) -> R (key peck) -> O (food) -S ( 950 Hz tone) -> R (key peck) -> O (no food) •Results in learned specificity, a change in the generalization gradient for less generality. •Next figure compares generalization gradients between animals given discrimination training to those given experience with just one of the contingencies.

Cerebellum and Timing

•Another brain structure important for skill learning is the cerebellum. -The cerebellum is evolutionarily ancient, appearing in some form in nearly all vertebrates. -Takes in inputs from the spinal cord, sensory systems, and cortex -Outputs primarily to the spinal cord and cortical motor systems -Lesions impair performance of motor sequences and eyeblink conditioning •In humans, cerebellar damage decreases initial skill and overall learning of mirror tracing. •On transfer tests, cerebellar patients even more impaired •Cerebellum may also be important for cognitive skill learning, as imaging studies show changes in activation during such tasks as mirror reading •Effects are lateralized, though reasons are not clear: -Left cerebellum activity decreases. -Right cerebellum activity increases.

Apraxia

•Apraxia—poor coordination of purposeful, skilled movements; most commonly from head trauma or stroke •Cortical damage often causes selective apraxia: -Left parietal damage causes difficulty imitating actions. -With frontal damage, cannot pantomime actions with two hands. •Skill memory may also be impaired, as patients can also have difficulty recognizing the performance of these skills.

Philosophical Traditions: More Associationism

•Associationism was further elaborated by other empiricist thinkers, including: Aristotle (382-322 BC) John Locke (382-322 BC) William James (1842-1910)

Aversive Conditioning

•Aversive Conditioning: type of behavior conditioning in which a noxious stimulus is associated with an undesirable behavior, in order to modify or eliminate the behavior. Learning to avoid or minimize the consequences of an expected aversive stimuli. -EXAMPLES •Giving alcoholics nausea inducing drugs •Giving a dog a shock whenever they bark or jump on a stranger •Putting undesirable tasting nail polish on the nails of nail biters and thumb suckers

Encoding: Prior Knowledge Helps

•Background knowledge dramatically enhances encoding. •Study tip: Read before class! (reading after not as effective)

Odor Conditioning

•Exposure to shock (US) innately produces escape/avoidance behavior (UR) •CS is an odor, initially neutral •After CS is paired with US, CS comes to produce avoidance (CR) •Works with only 1 trial •Aversive Conditioning: new CS->CR reflex helps avoid noxious US

Basal Ganglia and Skill Learning

•Basal ganglia sits at the base of the forebrain •Collects input from throughout the cortex •Outputs to: -Thalamus->motor cortex -Brainstem •Regulates velocity, direction, and amplitude of movement •The basal ganglia seems to be particularly important in forming new skill memories: -Damage impairs the creation of procedural memories but not declarative memories. -Recordings show that skill training produces task-relevant coding of neural activity in the basal ganglia. -Imaging studies show increasing activity as skills are learned. •Two modes of radial arm maze: -Declarative (at left): half arms have food, but no markings. Rat must sequentially search baited arms, remembering which have been visited and when, a declarative memory. -Procedural (at right): half the arms are lit, illuminated arms always have food. Animal just has to learn that light->food, a habit or skill. •Each is selectively impaired by different brain lesions ... •Basal ganglia damage selectively impairs skill learning (at right, red line at bottom) but spares declarative memory (at left, red line with controls). •In contrast, damage to the MTL impairs declarative memory (at left, top red line) but spares procedural memory (at right, red line with controls). •Note that in declarative mode (at left), lower scores mean better performance, but in procedural mode (at right), higher scores mean better performance. •Activity in the basal ganglia changes during skill learning in ways that seem to reflect task learning. •Cued T-maze task: Cue given, signaling which arm would have food for that trial. •Early in training, most activity occurred during turning. •Late in training, 90% of neurons showed task-relevant firing, mostly at the beginning and end of the task. •Participants learned probabilistic categorization (predicted "weather patterns" signaled by playing cards, with each card only partially associated with specific weather conditions). •As learning progressed, activity in the basal ganglia increased, similar to the increased organization of activity observed with rats in the cued T-maze task. •The basal ganglia seems to be particularly important in forming new skill memories: -Damage impairs creation of procedural memories but not declarative memories. -Recordings show that skill training produces task-relevant coding of neural activity in the basal ganglia. -Imaging studies show increasing activity as skills are learned. •Despite this evidence, precise role of the basal ganglia is unclear: -Since basal ganglia are involved in movement, lesion effects on skill learning could be due to movement problems, not specific to learning. -It is also unclear if the basal ganglia are involved in consolidation of skill memory, storage, or both. -Some evidence suggests the ultimate site of storage is the cortex

Behavioral Economics and the Bliss Point

•Behavioral economics—the study of how organisms distribute their time and effort among possible behaviors •Bliss point—the ideal distribution for the organism; provides maximum subjective value - To measure, record the actual distribution of time and effort.

The Diencephalon May Help Guide Consolidation

•Both the MTL and frontal cortex are regulated by the diencephalon. -mammillary bodies -mediodorsal nucleus of thalamus •Korsakoff's disease: -Thiamine (vitamin B1) deficiency -Sometimes accompanies chronic alcohol abuse -Patients act like they have MTL damage, but damage is to diencephalon and other structures.

Extinction

•Breaking the association between the CS and US can extinguish the new CS->CR reflex: -Present the CS alone repeatedly. -Initially, CS evokes strong CRs. -With repetition, however, CS becomes less effective, similar to beginning of training. •. Extinction probably doesn't erase the CS-US connection, just inhibits it: -Stress, new context, and/or passage of time can make the CS effective again! -This suggests that the classically conditioned memory survived extinction.

Classical Conditioning: What are the rules?

•Classical conditioning seems to offer a straightforward rule for learning: just pair the stimuli (CS and US) you want associated -Note this is very satisfactory for behaviorists, as it depends only on the pairing of stimuli, not any internal state of the learner. •Unfortunately, it's not that simple!

When Dissimilar Stimuli Predict the Same Outcome//Sensory Preconditioning: Co-occurrence and Stimulus Generalization//Acquired Equivalence: Novel Similar Predictions Based on Prior Similar Consequences

•Co-occurrence of stimuli may increase generalization. •Example: -If you like the cookies at a new bakery, you may like their brownies. •Two common ways of studying this are sensory preconditioning and acquired equivalence. Sensory Preconditioning—Pairing of two dissimilar stimuli enables learning about one of them to generalize to the other. •Acquired equivalence—Prior training in stimulus equivalence increases amount of generalization between two stimuli, even if stimuli are superficially dissimilar •In Hall study, pigeons learned that dissimilar colors paired separately with the same color had the same result. - This generalization was demonstrated in a new situation.

Compound Conditioning & Overshadowing

•Competition can occur when two cues (e.g., tone and light) appear together, a paradigm known as compound conditioning. •The two cues compete with each other and neither produce as much learning as it would have if presented individually. •Overshadowing occurs when a more salient cue within a compound acquires more of the share of attention and learning than the less salient cue.

Conditioned Compensatory Response

•Conditioned compensatory response: a conditioned response that opposes, rather than being the same as, the unconditional response. It functions to reduce the strength of the unconditional response. •Homeostasis: The tendency of the body to gravitate toward a state of equilibrium or balance. • •Tolerance: A decrease reaction to a drug (or any stimulus) so that larger doses are required to achieve the same effect. •Conditioned compensatory response: a conditioned response that opposes, rather than being the same as, the unconditional response. It functions to reduce the strength of the unconditional response. •Homeostasis: The tendency of the body to gravitate toward a state of equilibrium or balance. • •Tolerance: A decrease reaction to a drug (or any stimulus) so that larger doses are required to achieve the same effect. Note the importance of the drug context (e.g., testing chamber) in enabling tolerance!

Configural Learning in Categorization

•Configural tasks require sensitivity to combinations of stimulus cues, above and beyond what is known about stimulus components. •Configural nodes can be applied to categorization learning, where humans learn to classify stimuli into categories. e.g., diagnosis from symptoms •Although models with configural nodes can accomplish complex tasks, they break down when the number of different stimuli becomes large: -Configural nodes must be available for every possible combination. -With many stimuli, too many nodes (combinatorial explosion) •More recent multi-layer distributed models use a pool of nodes that can be shaped by experience to represent configurations only as needed: -Only configurations relevant to experience are represented, thus avoiding the combinatorial explosion.

Schizophrenia and Acquired-Equivalence:

•Consistent with hippocampal abnormalities, schizophrenics show deficits in using relational information about associations. •Hippocampal abnormalities suggest schizophrenics should have difficulties with relational associations. •This has been tested with an acquired-equivalence task, where earlier equivalence between stimuli helps participants generalize additional associations. •Catherine Myers and colleagues adapted the acquired-equivalence procedure for animal conditioning for use with humans. •On each of several trials, participants see a cartoon face and two colored fish and are asked to learn which fish each person prefers.. •In phase 1, the participants might be asked to learn that a certain brown-haired girl prefers blue fish over green fish and that a certain other person (a blond-haired woman) also prefers blue fish over greed fish. •In phase 2, participants learn some new information: the brown-haired girl also prefers red fish over yellow fish. •Phase 3 is a testing phase, in which participants are quizzed on all the pairings they have learned so far. Intermixed with this testing are some critical pairings that the participants have never seen before. For instance, they are shown the blond-haired woman and asked if she is likely to prefer a red or a yellow fish. •Healthy adults reliably judge that the blond-haired woman prefers red fish over yellow fish. •They are showing acquired equivalence. •Although schizophrenics learn the basic associations, they fail to transfer across related stimuli. •Antipsychotics partially treat this impairment.

Encoding: Depth of Processing

•Craik and Tulving proposed that the more deeply you process information the better it is encoded. •Example: Memorize list of words with different depths of processing -Pronounce: low-level processing -Images: high-level processing -Imaged words remembered better later •OK, but what does it mean to deeply process information? -Perhaps it is the number/area of brain areas involved.

Visuospatial Sketchpad

•Delayed Non-Matching to Sample Task: •Novel object shown •Delay •Choose the non-matching object •Requires visual memory of object to be held in mind during short delay - a function of the visuospatial sketchpad

When Memory Fails

•Despite the old saying "you never forget how to ride a bike," research shows that skills do decay with non-use. •Skill decay follows a similar power law: -Rapid decay when practice is first terminated -Slower decay as time progresses •In addition to decay, skills can also deteriorate due to interference from newly learned habits. -Two finger-tapping sequences learned, either 1/day or both in the same day. -For the 1/day group, each night's sleep further improved performance, but for the 2/day group only the more recent sequence was improved by sleep. •Finally, similarity between learning and retrieval of the skill is also important (transfer-appropriate processing).

Attention-Deficit/Hyperactivity Disorder (ADHD)

•Difficulties with: - Planning, organizing time - Keeping attention focused on a task - Inhibiting response to distracting stimuli •May involve dysfunction in PFC cortical and subcortical connections, including cerebellum and basal ganglia •Children with ADHD may have smaller right PFC than other children -Area is associated with spatial attention and working memory -Ritalin and other medications are stimulants that increase dopamine release or block its synaptic reuptake for 3-4 hours. •Genes associated with ADHD may be involved in dopamine regulation in the brain.

Shared Elements and Distributed Representations

•Distributed representation—each stimulus is represented by overlapping sets of nodes or stimulus elements. -Distributed: Each color is represented by 3 adjacent nodes. -Shared Elements: Each node is shared by >1 color. -Topography: physically similar stimuli at adjacent nodes (like sensory cortex!) •Distributed representation—each stimulus is represented by overlapping sets of nodes or stimulus elements. •Similarity between stimuli is explicitly represented by shared elements (more shared elements = more similar). •Because of this, models with distributed stimulus representations can generalize from past experience to novel stimuli.

Drug Addiction and Abuse: Linked to Classical Conditioning

•Drug tolerance increases with use in the same drug-taking context (situation-specific). •Even subtle changes (e.g., to drug taste) can overrun tolerance and increase drug effects. - Increases possibility of overdose In first-time dose rats, large heroin dose led to:96 percent fatal overdose. In rats with small heroin dose before larger dose in a different location: ••64 percent fatally overdose. In rats with small dose before larger dose in the same location: ••only 32 percent overdose. •Environmental CSs (e.g., appearance and smell of drug-taking location) produce CR drug craving in anticipation of US drug. •Relapse can occur from exposure to such powerful CSs. - Try to avoid as many cues as possible. - Need help from non-drug-using friends and family to avoid powerful CSs

Learning and Memory in Everyday Life—Kicking the Habit

•Drug-using environmental CSs may elicit intense cravings in recovering addicts. - Increases relapse vulnerability •Bouton (2000) suggests that therapists conduct cue-exposure therapy: - In different contexts, including home - Over varying time lengths - With small amounts of drug use!

Memory Consolidation and Reconsolidation

•Ebbinghaus was the first to observe an exponential forgetting curve: large amount forgotten early, almost nothing later. •Seems to show that initial storage is fragile and becomes stronger Consolidation is the name given to the theoretical process of strengthening the stability of stored information •Supporting the notion of consolidation, brain injury and disruption affects recent memories much more than late memories. •Suggests that the injury has halted/interrupted the consolidation process, preventing recent memories from being made permanent. •It may also be that each use of a memory makes it fragile again, requiring reconsolidation to once again keep it permanently. -Perhaps allows updating of the memory with new information -Therapeutically, suggests that reactivating memories may provide a chance to alter them.

Three Memory Processes

•Encoding - initial storage into memory •Storage/Consolidation - maintaining the stored memory •Retrieval - re-activating the memory for further processing

Practice: Feedback

•Feedback is essential for most types of learning. -Thorndike (1927) asked participants to draw lines exactly 3 inches long while blindfolded. -Half the participants were given feedback (told when they were within 1/8 inch); the other half was not. -Despite equal amounts of practice, only the feedback group improved. •What types of feedback are given to guide learning in college? -Does grade inflation pose a problem for effective learning? Why? •Frequency of feedback is also important: -Frequent feedback is helpful initially, but doesn't lead to high long-term performance. -Infrequent feedback causes a slower start, but usually leads to better long-term performance. •Most teachers/coaches intuitively vary feedback frequency to meet the needs of their students.

Apraxia: In the Lab

•For lab purposes, cortical function can be temporarily altered using transcranial magnetic stimulation. • •TMS is painless, as current is induced directly in the brain without affecting sensory neurons in the scalp. • •Depending on stimulation, can temporarily boost function or temporarily disable it(virtual lesion). Treatment sessions are approximately 40 minutes each, and administered 5 days a week. A typical course of rTMS is 4 to 6 weeks. However, this can vary depending on an individual's response to treatment.

Dual-Process Theory

•Groves & Thompson (1970) proposed that habituation and sensitization reflect differential activation of two different systems: -A low-threshold reflex pathway that weakens with repeated use -A high-threshold "state system" that, when activated, increases responses globally •Dual-process theory explains several features of habituation and sensitization: -Weak stimulus: primarily reflex pathway activation, stimulus-specific decline in responsiveness -Noxious stimulus: reflex+state system activation, generalized increase in responsiveness -Moderate stimulus: initial reflex+state system causes more responsiveness, but gradually, reflex weakening dominates •This model by Groves & Thompson (1970) can also help explain perceptual learning: -Two stimuli were repeatedly presented (e.g., circle and triangle). -Shared features will be experienced most often (e.g., blueness), leading to strong habituation to their presence. -Non-shared features (e.g., curves and angles) will be experienced much less often, accentuating their differences and providing a means for discriminating between them.

Errorless Discrimination Learning

•Herbert Terrace developed a training procedure called error discrimination learning. •Here, training begins with a discrimination task that is readily learned and then transitions to a similar but different discrimination task that is harder to learn, so as to eliminate or reduce, the errors made during the harder task.

Medial Temporal Lobes and Memory

•How do declarative memories get stored/consolidated in the cortex? •Consolidation seems to depend on the medial temporal lobes (MTL) -Hippocampus and surrounding cortex (entorhinal, perirhinal, and parahippocampal) •Evidence: -Lesions of MTL produce anterograde amnesia, the inability to consolidate declarative memories. -Hippocampus activity during learning predicts subsequent ability to remember. •Let's look at each of these in turn ... •Patient EP, with bilateral damage to the medial temporal lobes (MTL) similar to HM -Can directly copy a figure -> intact working memory -Can't draw figure from memory after a short delay -> failure to consolidate/store the memory of the figure •Similarly, animals with damage to the MTL show an inability to store new declarative memories (radial arm maze, scrub jays).

STM - Capacity

•How much is held in STM? -Miller: 7 +/- 2 items (5 is normal) Very SMALL capacity •Capacity and Meaning -When lists are meaningful, same length can be held in memory despite much more information being present. -Miller suggested that STM holds 5 to 9 "chunks" - units of meaning. •Quick decay (<1 min) and over-writing -Rehearsal - repeating information mentally to maintain attention •Transfer to/from LTM •Spoiler alert: Preferred term is now working memory, as it is the information you are currently working with.

Schedules of Reinforcement

•In operant conditioning, a contingency is learned: -If S, then R->O •Skinner reasoned that the form of this contingency would control the pattern of behavior. •Schedule: the pattern of behavioral contingency -If 10 Rs, then O -If 10 minutes and then R, then O •Skinner (and others) explored the influence of different schedules of reinforcement on behavior. •Partial (Intermittent) Reinforcement Schedules -Fixed-ratio - reinforce behavior after certain number of responses -Variable-ratio - reinforce behavior after unpredictable number of responses -Fixed-interval - reinforce first response after fixed amount of time -Variable-interval - reinforce first response after varying time interval

What Is Sensitization?

•Increase in the strength or occurrence of a behavior due to exposure to an arousing or noxious stimulus Example: more acoustic startle Sensitization: Quantification •Initial habituation to settle animals to a stable baseline •Foot Shock applied at dashed line to red group only •Sensitization: increased responding to start stimulus after shock Characteristics of Sensitization •Sensitization is also ubiquitous - found throughout the animal kingdom. •Sensitization also shows a set of common characteristics: -Spontaneous recovery, short- and long-term forms, massed better than spaced -Noxious (painful) stimuli work better than weak -More generalization, less stimulus specificity -Can develop with just a single noxious stimulus •A conserved mechanism to increase responses to stimuli that are important

Rescorla-Wagner

•Organisms try to anticipate important events from the stimuli around them •Each stimulus has a weight (V) for predicting a US -Weights go from 0 (no expectation) to 100 (certain) -A neutral stimulus has no expectations (Vs = 0) •Sum of the stimulus weights is the animal's prediction •When the prediction is wrong, the weights are adjusted -Error: difference between expectation and reality Error = Expected - Actual -Adjustment: each active stimulus adjusted by a proportion of error -This should decrease error next time this stimulus occurs before the US •When error is 0, no learning occurs (asymptote) •Rescorla-Wagner model explains blocking -Pre-exposure to light+US pairing enables organism to perfectly predict the US -During light+tone+US training, no unexpected US, and thus no learning about the tone -Therefore, no further learning and the tone remains ineffective •Also predicts many other features of CC •Overall, this model has been extremely influential and successful. •However, model only changes weights to the US, and cannot account for latent inhibition and other phenomena in which CS processing seems to change ...

Instrumental Learning: Thorndike

•Initially, lots of behaviors are tried out •Animal tracks outcomes of behaviors -S->R->O -In context/stimulus (S), Response (R) produces Outcome (O) •This knowledge guides future behaviors -Behaviors with positive outcomes increase -Behaviors with negative outcomes decrease S->R->O R: Response What is the R that is learned? •Initially, it was thought to be a rote motor program. •However, if normal motor program is blocked, animal will use other methods to achieve same ends. -Example: rats trained to wade through a maze filled partially with water. Later, maze flooded, making it impossible to wade. Nevertheless, they swam to the goal without problem. -Example: rat trained to press lever with paw. Paws tied to body, rat will crawl to lever and press with its nose. •R is a "Behavioral Unit": Not a single behavior but a class of behaviors producing an effect. Some cognitive psychologists would call it a goal or intention. S->R->O S: Discriminative Stimulus (Context) •Operant conditioning is about contingencies (If R, then O). •However, contingencies change. -If I cry, mom picks me up ** Only if mom is sober! •Discriminative Stimulus (S): tell us which contingencies are in effect -If R, S - O -If R (no S), does nothing •Operant conditioning is really a three-part association: Context/Discriminative Stimulus, S -Behavioral Response, R -Outcome, O •Discriminative stimuli are crucial in this type of learning, ensuring that we select behaviors that are appropriate to the situation. -Example: You would only put money into a pop machine that's working. -Example: Rats trained to press a lever for food will learn the sound of the equipment being turned on, and will only press the lever when it is actually functioning.

Mechanisms of Perception// Perceptual Learning//Spatial Learning

•Input from each sense is relayed to specialized sensory cortex (e.g., somatosensory cortex at right) •Each neuron within sensory cortex has a distinct receptive field—part of the world it responds to (e.g., touch to the lip) •Receptive fields are well organized in the cortex, forming orderly maps. Perceptual Learning: •We now know that these maps are not fixed, but change with development and experience. •Cortical plasticity: refinement in the receptive fields of neurons of the sensory cortex due to development or experience •Even modest practice can temporarily rewire these maps; repeated practice can make this permanent ... Spatial Learning: •The hippocampus has "place cells," cells whose receptive field seems to be a particular location or place that is familiar. •In the above example, a place cell in a rat fires in arm 2 of the maze. Rotating the landmarks shows that the place cell defines "arm 2" based on these landmarks.

Philosophical Traditions: William James

•James proposed that experience links ideas in the mind. •Remembering one idea would spread along links, retrieving a complex episode. •these links would be physically formed in the brain, providing an early link between psychology and neuroscience.

William James

•James proposed that experience links ideas in the mind. •Remembering one idea would spread along links, retrieving a complex episode. •these links would be physically formed in the brain, providing an early link between psychology and neuroscience.

Atkinson-Shiffrin Memory Model

•Long-Term Memory Systems: -Declarative/Explicit (Chapter 7) •Semantic •Episodic -Non-declarative/Procedural/Implicit/Skill Memory (Chapter 8) •Learned through repetition, apparently infinite capacity, stored knowledge not currently "in mind" Sensory Memory -One for each sense -Very large storage -Extremely rapid decay (~1s) and rapidly over-written by new incoming sensory information -Transfers to STM STM Multimodal (general for senses) Small capacity Quick decay (<1 min) and over-writing Rehearsal - preserves info in STM Transfer to/from LTM Sensory memories are brief, transient sensations of what you have just perceived. One for each sense Very large storage Extremely rapid decay (~1s) and rapidly over-written by new incoming sensory information Transfers to STM

Basal Forebrain May Help Determine What the Hippocampus Stores

•MTL is regulated by the basal forebrain—structures at base of forebrain -Medial septum, releases acetylcholine and GABA into hippocampus via the fornix •Certain strokes can lead to basal forebrain damage, resulting in anterograde and retrograde amnesia. - e.g., anterior communicating artery (ACoA) aneurysm •Survivors may confabulate (confuse free associations with reality).

Other Models

•Mackintosh has proposed a model of classical conditioning focused on attention, and the way the CS is processed: -Stimuli have a salience that determines attention. -Repeated exposure with no consequences decreases salience (attention), a form of habituation. -In latent inhibition, pre-exposure to the CS decreases attention for that stimulus, making it harder to learn about in the training phase. •Attempts have been made to integrate both CS-focused (Mackintosh) and US-focused (Rescorla-Wagner) approaches: -Wagner's SOAP model (Sometimes Opponent Process) -Surprising complexity to this "simple" form of learning

What is memory?

•Memory: the record of our past experiences, which are acquired through learning

Memory Failure + Memory Failure: forgetting + Memory Failure: Interference

•Multiple possible failure points •Four common problems: forgetting, interference, misattribution, and false memory Memory Failure: forgetting •Even with perfectly encoded material, there is substantial forgetting (e.g., in memory for TV shows since time of airing). •Forgetting slows down with time, so that very long-lasting memories tend to be permanent. •Directed forgetting (telling people to forget) can increase forgetting somewhat.

Comparator Model

•New stimulus compared with memory for stimulus •If there is a strong match, pay no attention •If there is not a strong match, pay attention and respond •Responding builds better memory •Explains habituation, as increasing quality of representation decreases responsiveness •Also explains perceptual learning, as representation and ability to recognize keep increasing •But: Hard to explain what a memory "match" is!

Differentiation Model

•New stimulus compared with memory for stimulus •Responding builds better memory by adding a bit at a time to the representation •Similar to comparator theory, but more generalized; no claims about the relationship between match and responsiveness •Connects the slow build of the memory to the limited capacity of the brain to take in information (little bit at a time)

Behavioral Processes

•Operant conditioning is the process whereby organisms learn to make responses in order to obtain or avoid certain outcomes. •"Discovered" by Edward Thorndike -Studied how cats learned to escape from puzzle boxes

Parkinson's Disease

•Parkinson's disease—increasing muscular rigidity, tremors, difficulty initiating movements -Reduction in brainstem neurons that modulate basal ganglia and cerebral cortex activity -Decreased dopamine (can be given medication to increase dopamine levels but too much can cause Schizophrenic symptoms) -Difficulty learning some motor tasks -Can learn mirror reading Parkinson's disease most often develops after age 50. It is one of the most common nervous system disorders of the elderly. Nerve cells use a brain chemical called dopamine to help control muscle movement. Parkinson's disease occurs when the nerve cells in the brain that make dopamine are slowly destroyed. Without dopamine, the nerve cells in that part of the brain cannot properly send messages. This leads to the loss of muscle function. The damage gets worse with time. Exactly why these brain cells waste away is unknown. Mirror writing is formed by writing in the direction that is the reverse of the natural way for a given language, such that the result is the mirror image of normal writing: it appears normal when it is reflected in a mirror. Mirror reading is the same for reading tasks. •Drug therapies and surgical procedures may temporarily relieve symptoms (e.g., deep brain stimulation to basal ganglia cortical loop). DBS directly changes brain activity in a controlled manner, its effects are reversible (unlike those of lesioning techniques), and it is one of only a few neurosurgical methods that allow blinded studies.[ May have seen this type of treatment for Tourette's.

Practice: Implicit Learning

•Participants were given a cue and then pressed an associated button as rapidly as possible. •Cues were usually in random order, but a 10-item sequence sometimes occurred. •Participants became very fast at the 10-item sequence, as they could anticipate each subsequent key. •Interviews determined, however, that none of the participants was aware of the sequence or could repeat it if prompted.

Drug Addiction

•Pathological addiction—a strong habit maintained despite harmful consequences -This involves craving a high "euphoria" and avoiding withdrawal. - Seeking pleasure involves positive reinforcement. - Avoiding pain involves negative reinforcement. •Although liking a drug may help initiate addiction, the incentive salience hypothesis suggests that addiction is maintained by "wanting" a drug. •All addictive drugs cause the release of dopamine from the ventral tegmental area. Drug Addiction: •Behavioral addiction—addiction to certain behaviors, rather than drugs -Produces euphoria -Understanding drug addiction may help understand/treat behavioral addictions. •Examples: -Compulsive gambling, eating, sex, Internet use, shopping, exercise, work Treatments: •Naltrexone (drug) treatment: -Indirectly inhibits dopamine production; may help treat heroin addicts and compulsive gamblers •(Cognitive) behavior therapies: -e.g., extinction, distancing, reinforcement of alternative behaviors, delayed reinforcement -Based on instrumental conditioning principles

Talent Takes Time to Blossom

•People who seem to master a skill with little effort are often described as having a talent for that skill. •Talent also plays a role: -Those who start off performing a skill well are most likely to end up becoming experts. -Is this because they had the right genes for expertise, or because early success helped them stick with the intense effort required? •Participants: pairs of identical (100% same genes) and fraternal twins (50% same genes) •Rotary Pursuit Task: keeping a pen overtop of a rotating target •Results: -Practice effects: All participants became skilled at this task (at right). -Genetic effects: Identical twins were more similar in their performance than fraternal twins (next slide). Relative impacts of talent and effort depend on the context evaluated. With same amount of practice, talent effects are evident:••Two pianists who've both taken lessons for 10 years ••One is accepted to Julliard; the other is not ••Given same amount of practice and effort, probably due to talent With same talent, practice effects are evident:••Two identical twins ••One becomes a concert pianist, the other doesn't ••Clearly due to effort alone, as they are genetically identical •Although both talent and practice contribute to expertise, practice is quite powerful. •Some psychologists maintain that practice alone is sufficient to become an expert in any domain (though perhaps not world-class).

Power Law of Practice

•Power law partly explains why deep expertise is so rare: -Little practice is required to gain reasonable skill. -With every gain in skill, though, additional gains take even more time. -Extreme practice is required to gain advanced skill. -Few people have the time, energy, and interest to pursue the highest levels of skill in a domain. •feedback can reset the power law of learning: -Participant learned to kick a target rapidly -As performance gains were slowing, was shown a film demonstrating additional techniques for improvement -After gaining this source of feedback, an additional power curve of performance increase

Practice: Massed vs. Spaced

•Practice can be spread out in time (spaced) or crammed together (massed). •Spaced practice is much more effective. -Postal workers trained on a sorting machine achieved expert proficiency in fewer hours of practice at 1 hour/day compared to 2 or 4 hours/day.

Latent Inhibition

•Pre-expose to CS repeatedly •Then pair CS with US •Learning is inhibited •Animal has learned that the CS is useless, has stopped paying attention •Another blow to behaviorism

Operant Conditioning: Basic Pattern

•Pre-training - low spontaneous rate of R •Training - contingency is introduced: If S, R->O •Acquisition - animal discovers contingency, rate of R increases •Extinction - contingency is eliminated (R->__), rate of R decreases •Note that R has a low initial rate; the animal must discover the contingency.

Frontal Cortex and Working Memory

•Proportions of the prefrontal cortex (PFC) vary among mammals. •Mammals with better working memory function tend to have proportionately larger PFC areas. •PFC proportions are similar between humans and their close primate relatives.

Eyeblink Conditioning

•Puff of air to eye (US) innately produces eyeblink (UR) •CS is a tone or light, comes to produce a gradual eye closure (CR) •A form of Aversive Conditioning: CS->CR prepares to avoid US •Works on rabbits and humans, but takes many trials Note how, initially, the CS (tone) causes no response The effectiveness of the CS builds gradually over many pairings with the US In most cases, classical conditioning builds gradually over many trials. •Plots show % of CS (tone) exposures that produce a CR (anticipatory eyeblink). •Initially, CS exposure never produces a CR. •Over time, nearly every CS produces a CR.

Chapter 2 2/3 of lecture

•Reflexes are natural, automatic responses to stimuli. Early neuroscientists believed that all complex learning involved combining simple spinal reflexes. •In the brain, sensory signals are initially processed in cortical regions specialized for processing such signals, and lead to activity in other cortical regions that are specialized for coordinating movements. •The neural transmission that enables stimuli to generate responses takes place across synapses: the presynaptic neuron releases neurotransmitters into the synapse; these chemicals cross the synapse to activate receptors on the postsynaptic neuron. •Functional neuroimaging methods allow researchers to track brain activity during the performance of memory tasks by measuring changes in glucose utilization and blood oxygenation in different brain regions. •Electroencephalographic recordings make it possible to track the activity of large populations of neurons over time. •Single-cell recordings allow researchers to directly monitor and record the electrical activity of single neurons and changes in their firing patterns that occur during learning or the recall of memories.

What type of memory?

•Remembering how to ride a bike-- Nondeclarative (explicit) •Remembering the first time you rode a bike--•Episodic (explicit) •Remembering who is the current president of the U.S.--•Semantic (explicit)

The Hippocampus in CS Modulation

•Removal of the hippoampus: -Does not alter basic classical conditioning paradigms -But does eliminate latent inhibition -Also disrupts other paradigms that depend on changes in the processing of the CS •Perhaps: -US modulation (Recorla-Wagner) occurs in the cerebelum -CS modulation (Mackintosh) occurs in thehippocampus and medial temporal lobe

Schizophrenia, Working Memory, PFC

•Schizophrenia affects many behaviors and many brain regions, but two prominent symptoms include: -Poor working memory, especially tasks involving central executive function (manipulation) -Altered frontal lobe function, especially in the DLPFC •Example -Schizophrenics do poorly on the Wisconsin card-sorting task. -They also fail to show anincrease in DLPFC activitywhile completing the task. Why???

Episodic Memory in Scrub Jays

•Scrub jays bury worms and nuts in sand-filled ice-cube tray compartments. -When allowed to recover food 4 hours later, chose worms (favorite food) -After 124 hours, tended to choose the still-edible nuts -Suggests an ability to recall specific details of what was buried, where it was buried, and when it was buried—an episodic memory?

Man-Machine Interfaces

•Sensory prostheses—mechanical devices; interface with neurons to produce sensation •Example: cochlear implant -Electrically stimulates the auditory nerve -Need training to interpret these "virtual sounds" (perceptual learning) -Training yields initial rapid improvement with slower gains in discrimination learning over time -Recency of hearing loss is a factor in implant success.

Evolution and Natural Selection

•Similarities among living creatures strongly suggests that species evolved from common ancestors. •Natural selection provides a plausible explanation for evolution: variations in heritable traits that provide reproductive advantages increase in frequency, leading to changes in species and the evolution of new species. The Darwin family played a major role in initiating the evolutionary framework for understanding life: -Erasmus Darwin was an early proponent of evolution. -His grandson Charles Darwin developed the idea of natural selection. -Francis Galton, also a grandson of Erasmus, developed many statistical and experimental techniques for studying variation (but also founded the tragic eugenics movement).

Classical Conditioning: Brain Substrates

•Since Pavlov, there has been keen interest in understanding how classical conditioning works at the neural level. •In the 1980s, Thompson and associates discovered that eyeblink conditioning in rabbits depends on the cerebellum. •Since then, Thompson'0 slab has worked out considerable detail on how the cerebellum supports classical conditioning

Associative Bias

•Some associations are innately easier to make: -When tone + taste paired with poison, only taste provokes CR -When tone + taste paired with shock, only tone provokes CR -In nature, tastes go with getting sick, sounds with getting hurt •Seems we have some innate preferences for forming associations that can override statistical correlations

What does the prefrontal cortex do?

•Storage: holds temporary memories in place (this is the traditional view) •Coordinates: maintains activity in posterior portions of the cortex to represent temporary memories (this is a newer theory) •Still unclear which perspective is correct

Stroke: Habituation Gone Awry// Stroke: Treatment for Learned Non-Use

•Stroke -Disruption of brain blood flow, which rapidly causes brain damage -Leading cause of brain damage in the U.S. •Learned Non-Use -Stroke can cause loss of sensation without loss of motor control. -In these cases, though, patients can end up ignoring and not using the desensitized limb. -This seems to be a maladaptive instance of competitive (Hebbian) plasticity: the lack of sensory input from the limb causes it to "lose" attention and resources relative to the healthy limb. Stroke: Treatment for Learned Non-Use: •In constraint-induced movement therapy the "good" limb is restrained, forcing use of the desensitized limb. •This gives a chance for use of the damaged limb and can improve behavioral performance and expands cortical representations for the limb.

Prefrontal Control of Long-Term Declarative Memory

•Strong activation of dorsolateral prefrontal cortex during: -Retrieval of past memories -Remembering the source of past memories (below: participants learned words in two tasks and then were asked to remember which task for each word)

Chapter 2 1/3 of lecture

•The brain and spinal cord make up the vertebrate CNS. The brain controls behavior through connections with the PNS. •The vertebrate brain is made up of several different regions that contribute to learning and memory. •Neurons are capable of changing their function and modifying the way they process information. •Modern structural brain-imaging techniques provide ways to measure variations in the brain structure of living humans without causing harm. •Techniques for imaging neural structures in non-humans make it possible to collect detailed information about neural changes that occur during learning. •Enriched environment studies show that learning experiences can have a profound impact on brain structure and on an individual's learning and memory abilities.

Central Executive and Cognitive Control

•The defining activity of the central executive is the manipulation of remembered information. •Researchers use a variety of tasks to study central executive function ... Self-ordered memory task for monkeys The monkey sees three distinct containers and selects a reward from one of them. Their order is shuffled with each trial and the monkey must remember which container has the reward. •Switching between tasks also requires cognitive control. •In the Wisconsin Card Sorting Test: -Patients try to learn a rule governing the sorting of cards (e.g., by color). -After they catch on, however, the rule is changed (e.g., by shape), requiring an updating of memory and behavior. •The central executive also plays a role in selecting appropriate behaviors and inhibiting inappropriate behaviors. •In the Stroop task, participants name the color of the ink used to print a set of words. •Cruelly, the words name colors different from the ink (e.g., word "blue" written in red). -Select name of the color of the ink -Inhibit saying the name of the word

Frontal Cortex, Storage, and Retrieval

•The frontal cortex may play an organizing role in declarative memories: -Selecting information to be encoded into long-term memory -Retrieving information back into working memory •Evidence: -Frontal lobe damage causes problems of source memory, suggesting problems of retrieving complex memories. -Frontal lobe seems to control hippocampus activity, possibly guiding the consolidation process. •We'll look at this more closely. •During learning, some regions of the frontal lobe predict increased MTL activity and memory. •During directed forgetting (below), other regions of the frontal lobe predict reduced MTL activity and memory. •Suggests that the frontal cortex can manage the MTL and consolidation

Retrieval: More Cues, Better Recall

•The more cues provided, the easier it is to recall a memory: •Recognition test (question + response options) •Cued recall (question + prompt) •Free Recall (question alone) • •Example: What form of memory is for facts and general knowledge?

Nonhuman Episodic and Semantic Memory?

•These memories are difficult to assess non-verbally, but some approaches are possible. •Radial arm maze indicates semantic memory in rodents: -Food always placed in a specific food arm. -Rat always starts from a specific start arm. -After training, rat is started from a new arm but navigates directly to the food arm. -This demonstrates flexible use of memory, a hallmark of semantic memory. •What about episodic ...

Models of Classical Conditioning

•Timing effects, blocking, latent inhibition, and associative bias show that the "rules" for classical conditioning are quite complex. •Researchers have thus turned to models of classical conditioning—formal sets of rules for when learning will occur: -The hope is that a simple model will be able to explain the complexity of classical conditioning. -Mis-match between model and data provides clues to what we still need to understand. •There have been two popular traditions in models of classical conditioning: -US modulation approaches - in which learning changes processing of the US, e.g., Rescorla-Wagner -CS modulation (attentional) approaches - in which learning changes processing of the US (e.g., Mackintosh)

Clinical Perspectives: Transient Global Amnesia

•Transient global amnesia—temporary memory disruption •Can be caused by head injury, low blood sugar, heart attack or stroke, tranquilizers, alcohol "blackouts" •Case of SG, caused by blood flow disruption during surgery •Imaging studies suggest transient abnormalities to hippocampus Functional Amnesia: Functional (or psychogenic) amnesia—results from psychological (rather than physical) cause e.g., dissociative fugue •Loss of personal identity due to severe psychological trauma - Can be faked for personal gain PN and Functional Amnesia PN (or Lumberjack) = case study of a 21-year-old man Severe retrograde amnesia for episodic memories; intact language skills and semantic memory One week after onset, a movie funeral on TV triggered his recovery. Extreme grief from his grandfather's death may have precipitated fugue. He encoded no events during the episode due to temporary anterograde amnesia. In another case, PET scan found: Decreased glucose metabolism in MTL and medial diencephalon (structures involved in memory storage and retrieval)

Subcortical Structures Involved in Episodic and Semantic Memory

•Two additional structures play important roles in regulating episodic and semantic memory: the diencephalon and the basal forebrain. •Damage to either can cause anterograde amnesia.

Classical Conditioning

•Unconditioned Stimulus (US): a stimulus that naturally (without conditioning) evokes some response. •Unconditioned Response (UR): the natural response that occurs with the unconditioned stimulus. •You DO NOT need learning with the US and UR, the relationship occurs naturally •Conditioned Stimulus (CS): A cue that is paired with an unconditioned stimulus and comes to elicit a conditioned response. •Conditioned Response (CR): the trained response to a conditioned stimulus in anticipation of the unconditioned stimulus that it predicts. •Begins with an innate (unlearned) reflex -Unconditioned stimulus (US) [food] -Unconditioned response (UR) [salivation] •A neutral stimulus (CS) is then repeatedly presented before the reflex is triggered, producing a new reflex -Conditioned stimulus (CS) [bell] -Conditioned response (CR) [salivation] •Classical conditioning helps an organism prepare for the future (the bell triggers behaviors to prepare for the food) •Classical conditioning represents an association between the CS and the US (bell is associated with food) -A chance to test principles of association proposed by Aristotle Did you follow the changes? The UR and the CR are the same response, triggered by different events. The difference is whether conditioning was necessary for the response to happen. The NS and the CS are the same stimulus, too.

Encoding: Mere Exposure is Not Enough

•Unfortunately, simple repetition is not an effective way of encoding new memories! •For example, you've probably seen a penny thousands of times, but all that exposure has probably not helped encode the visual details of a penny. •Study tip: Just re-reading notes/book is not enough! •There's got to be a better way ...

3 Types of Simple Learning

•We frequently encounter the same stimuli day after day: -Same social contacts -Same locations -Same classes •Most organisms can learn about stimuli that are frequently encountered. Habituation: decreasing responses to a frequent but innocuous stimulus Sensitization increasing responses to a noxious/ arousing stimulus Perceptual learning becoming better at processing/ recognizing a frequent stimulus

Using the Past to Cope With the Present

•We often need to respond to stimuli that are completely novel. -Will I like cauliflower? I've never tried it before! •Rather than respond randomly, we can bring to bear prior experience with stimuli we have encountered. -Cauliflower reminds me of broccoli. I have tried that, and didn't like it. •There are two basic ways of using these past experiences... There are two basic ways of using these past experiences Generalization: transferring past experiences to new situations Cauliflower is probably like broccoli; I probably won't like it either. Generalization helps apply the lessons of the past to the present. However, generalization can make us blind to circumstances that have changed. Discrimination: the perception of differences between stimuli Cauliflower is probably not like broccoli; I might like it or I might not. Discrimination opens us up to new experiences. But discrimination can also waste time and effort learning things we should have already known. •The right balance: -Specificity: applying the past narrowly; discriminating -Generality: applying the past broadly; generalizing •How do we find this balance? How do we learn when to generalize and when to discriminate? We'll look at learning under several different conditions Generalization vs. Discrimination •We'll look at these different scenarios in turn. •We start with what seems to be our default: generalizing to similar stimuli.

Models of Skill Memory

•What is actually occurring as a skill is learned? •Fit (1964) proposed a 3-stage process that eventually builds a motor program - a sequence of movements that an organism can perform automatically. Example: Driving a car---Cognitive stage: clumsy and slow; needs explicit conscious control; rules are often rehearsed verbally (e.g., check the mirror; hands at 10 and 2; etc.)---Associative stage: many stereotyped movements learned (e.g., shifting, changing lanes), but still exerting conscious control to determine the correct sequence and monitor performance---Autonomous stage: can drive while texting, talking, changing the radio (though you shouldn't!)

Cognitive Approach

•While behaviorism improved the rigor of psychology, its exclusive focus on behavior was too narrow. •The cognitive drew inspiration from computer technology to expand the horizons for psychological research: Reintroduced mental processes in a rigorous way Focused on the behaviors and processes that humans specialize in (language, reasoning, and planning) Accepted intrinsic motivation to learn and remember in addition to the Law of Effect Prominent figures include Estes (mathematical models), Bower (insight), Miller (7 +/- 2), and Rumelhart (connectionism)

Encoding New Memories: Repetition

•With effective practice, performance increases. •Remarkably, the pattern of performance gain is similar across tasks and species. Power law of practice: Gains are rapid at first, but decrease proportionate to what has already been learned.

Discrimination Training

•With feedback, one can learn to tell even subtle differences in stimuli. •Seems impossible? With practice and feedback, humans and other animals can learn to make such fine distinctions. •Let's see the results in graph form •Note the increase from guessing (near 50% correct) to near perfect ability to detect these subtle differences. •Unfortunately, these awesome skills don't generalize much: learning specificity -Note that even a small change (90° rotation) sets experts back to 0!

coordinates retrieval

•Working memory doesn't just maintain temporary memories, it also coordinates retrieval of long-term memories. -Like other executive functions, seems to depend on the DLPFC ...

Huntington's Disease

•inherited; causes damage to brain neurons (especially in basal ganglia and cerebral cortex) •Symptoms include: - Psychological problems (mood disorders, hypersexuality, psychosis) - Slow loss of motor abilities - Early facial twitching and progressive shaking of body parts •Specific impairment of skill/procedural learning once disease emerges: -Can slowly learn new skills -Can learn some cognitive tasks, such as Tower of Hanoi puzzle -Perceptual-motor skills also hindered by movement impairments Average lifespan after onset of symptoms is 10-20 years.

Hermann Ebbinghaus

•was a poor post-doctoral student. •Ebbinghaus studied memory in a distinctly modern and scientific way: -Empirical -Experimental -Quantitative: