NS 101C Module 3
You can induce false memories in a lab using semantically related list of words. What does this show?
When you hear these words, you may be activating other words that are related to it Activation of a memory may be confused with the sensory experience of it.
What is devaluation?
When you make a previously rewarding outcome result in no reward after the same stimulus response. However most of the time you will continue to do the stimulus response because it has become habitual "Force of habit"
What is the Radial Arm maze and what does it test for?
Win-shift strategy (visit each arm only once) testing for ability to remember events or something special about spatial configuration
Characteristics of Covert Attention (2)
You can attend to a location that is different from where you are directing your eyes Although where you are looking and where you are attending are normally the same, they can be decoupled Ex: no look pass in basketball
Conditioned fear stimulus and unconditioned fear stimulus converge at what area in the amygdala?
basolateral group (lateral amygdala)
What is BOLD signaling?
blood oxygen-level dependent (BOLD) signal method used in fMRI to observe which parts of the brain are currently active
What is the most important influences of declarative memory encoding?
-"depth of processing" -Items that are processed for meaning (deeply) are remembered better than items processed for physical characteristics (shallowly)
What is one reason of late selection models is supported even though it would be a waste of resources to intake everything?
Ability to focus on convo you weren't paying attention to when someone calls your name
What is the memory systems approach explain?
Memory is not a unitary phenomenon, but comprised of difference systems Systems have different behavioral properties and depend on different brain systems
Conceptual (semantic) Priming is associated by which cortical areas?
Reductions in the left inferior frontal region. Areas that do deep encoding when you make deep/ semantic connections
What is working memory?
contents of awareness at any one time: a newer understanding of short-term memory that focuses on conscious, active processing of incoming auditory and visual-spatial information, and of information retrieved from long-term memory has limited capacity
Motor Skill learning appears to be support by what kind of changes?
Changes within the structures of the motor system, and not within a control structure
Jean Piaget gives an example of a characteristic of false memories. What is that?
False Memories can be very vivid. He remembers very vividly/ seeing in his mind when he was almost kidnaped as a child. But when Jean was 15, the nanny had confessed that she lied about that story. Real life app: eyewitness testimonies
What does orienting activate?
inferior parietal sulcus lobe, frontal eye fields (dorsal attention system)
Effective memory depends on what (during working memory and recall)?
inhibitory control of information in working memory, and using effective strategies during recall
What is repetition Suppression?
is a reduction of neural response that is often observed when stimuli are presented more than once
Is the hippocampus responsible for fear conditioning to a cue (tone or light)?
no
Executive control abilities depend on what cortex?
prefrontal cortex
After post learning, why are subjects better able to recognize oblique tilt patterns just as well as the horizontal patterns?
The subject recruited neurons to help with this kind of discrimination which is reflected in more BOLD signaling/ blood flow to those areas.
What is the competitive Nature of retrieval?
When you are actively retrieving information, you will inhibit related information. So in order to effectively retrieve something, we have to make competing information less accessible. EX: tip of the tongue phenomenon; the expression of the memory is temporarily inhibited
What are the difficulties with testing patients with damages to the motor system?
They show impaired motor performance and wouldn't be able to see the difference between random and learning tasks at all
What is Fragment completion?
-Fragment Completion Pictures: When you had seen the full picture before hand, you can complete the picture in a more fragmented way. -Fragment Completion with words: you are able to guess the fragmented words more when you were shown the full word beforehand Amnesiacs can still show improvement in these cases showing priming occurs without working declarative memory
What are the characteristics of declarative memory (5)?
-Memory or facts and events -You are aware of what you are remembering -Can be verbalized -Memory can be used flexibly in new situations -Depends on medial temporal lobe
Characteristics of Motor Skills (4)
1. Gradual learning via practice 2. Difficult to verbalize what has been learned 3. Independent of Medial Temporal Lobe (used for declarative m) 4. Amnesic pts show normal learning of motor skills even when they don't remember training events
What are 2 reasons thought to explain why memory fails?
1. All encoded information remains in memory but can't always retrieve it. May be due to retrieval failure instead of memory failure. - if the correct retrieval cue is given a memory can be uncovered (like temporary amnesiacs?) 2. Actual forgetting of memories that were once encoded are lost - forgetting can happen if memories are weak, not practiced, or there is a lot of interference. Changes deteriorate over time.
2 types of Visuomotor Skills in the Lab
1. Mirror Tracing - The mirrortracing activity is a visual and motor test that involves learning a new motor skill. The task requires you to move a pencil to trace the diagram of a star while looking at your hand only as a reflection in a mirror - Errors: crossing over a line - Slowly over several trials, the number of errors will go down day by day showing that even though HM didn't remember doing the task, he would still be learning. 2. Rotor Pursuit - Measure of motor skill learning in aging Pt holds a wand and keeps it on a target on a turntable-like platter.
Characteristics of Nondeclarative Memory (5)
1. Not aware of what you are learning 2. But you can show learning because you are getting better at something 3. cannot verbalize what you have learned (not accessible to consciousness) 4. learning tends to be inflexible-tied to specific situations and not generalizable 5. Learning is independent of medial temporal lobe
What are 2 things that need to be accomplished for the episodic memory to be considered episodic?
1. Pattern separation - make each episode unique and store it separately -Need to make each episode unique -Orthogonalize each in order to store them 2. When given a partial cue, you need to be able to reactivate the memory representation in order to retrieve it
What were the results of the dual-task conditions in the dual weather prediction test (4) ?
1. Reduce declarative knowledge but not classification learning. 2. Learning under single test (no distractions), your declarative test is good, and learning under distraction => less flexible nondeclarative learning happens 3. Dual-task training leads to a different functional anatomy for subsequent task performance (putamen) 4. Habit learning is less sensitive to attention unlike declarative learning
What are 5 ways to measure episodic memory?
1. Remember/Know Test 2. Associative recognition 3. Source memory -------------------------------- 4. Autobiographical interview 5. Krovitz method
Characteristics of perceptual learning (4)
1. Slow and gradual 2. depends on experience 3. usually can't verbalize how you are performing the task 4. very specific to the domain of learning (doesn't necessarily transfer, even to other regions of the visual field i.e. seeing it at the top of a page vs at the bottom of a page)
Karpicke & Roediger 2008 Study - Testing as the best form of studying
1. Study all 40 Swahili words and test on all 40 words each time (ST) 2. Test all 40 words each time, but drop word from Study if you got it right (SNT) 3, Study all 40 words each time, but drop it from test if you got it right (STN) 4. Drop a word from study and test once you get it right (SNTN) Found the groups that continued to test on all 40 words (group 1 and 2) did the best. Key finding was that there was a huge benefit of testing on memory retrieval.
What are 3 problems to the high road/ low road theory?
1. There doesn't seem to be a visual low road (projections from the visual system to the thalamus). Specific to the auditory system 2. Timing is only about 20-30 ms different but the amount of time to initiate a fear response is much longer 3. The thalamus alone isn't good at processing stimuli
Characteristics of the human amygdala (3)
1. fearful faces and emotional pictures activate human Amygdala 2. For emotional material, amygdala activity at study correlates with better memory 3. Laterality difference related to sex (men=right, women=left)
What are some examples of priming?
1. fragment completion 2. Perceptual identification 3. Visual tests, but occurs in other modalities (homophone spellings after hearing related story beforehand (read vs reed) 4. Semantic Priming (category exemplar generation)
3 Effects of amygdala damage in humans
1. pts w/ amygdala damge do not show enhancement of perception and memory of emotional material 2. Impaired fear conditioning in amygdala pts 3. Double dissociation with amnesic pts in fear conditioning Amnesiacs will have a CR but even though Urbach-Wiethe are conscious, they don't exhibit a CR to a shock stimulus.
What is the win-stay learning on the radial arm maze?
A cue (like a light) signals the presence of reward on the arm The learning is very gradual- maybe because it goes against win-shift tendency
How is parietal lobe function related to spatial attention? Results of the green line receptive field task
Activation around intraparietal sulcus associated with voluntary direction of attention Number of activated voxels in the intraparietal region was tied to performance level across and within subjects Relationship between performance and number of voxels was an inverted U
Selective Hippocampal activation during recollection. What does this mean in the role of hippocampus?
Actually recollecting the moment you remember the memory there was more blood flow to the hippocampus which suggests that it does play a specific role in episodic memory
What is priming?
After being exposed to a stimulus, you can process it a little more quickly and accurately the next time. It is an example of nondeclarative learning in that you are not necessarily aware that learning occurred not flexible
Intracranial recording of patients for epilepsy surgery
Alternately show lights and sounds with different frequencies offsetting each other. They would need to focus on one or the other. When they have alternating attenuation, the sinusoidal graphs would shift 1 period and the entrainment would go out of phase.
Role of Amygdala in Learning
Although you don't need the amygdala for declarative learning, you do get a boost in memory for emotional material (words like murder/ leukemia; gorey pictures, etc)
Both contextual fear and cued fear depends on what part of the brain?
Amygdala
What is win-shift strategy?
An organism changes responses when rewarded and maintains the response when not rewarded
What does alerting activate?
Ascending norepinephrine system
Declarative memory encoding is sensitive to what?
Attention -if you are distracted, declarative learning is impaired -attention is a limited resource- if you are devoting it to something else, there is less available for deep encoding
What are the differences between overt and covert attention?
Attention- enhanced processing of a subset of the environment Overt Attention: we "foveate" things we want to attend to (high visual precision focus) Covert Attention: attention that is directed to a region that is not on your fovea
Results of the Desimone receptive field studies
Attentional modulation in V4 occurs <100 ms after stimulus onset. Attentional modulation in V1 (striate cortex) occurs much later Thus, it appeared that this reflected feedback from higher visual areas
Why would we have different systems of attention?
Automatic attention systems can help us against dangers that we are not currently focused on. Very adaptive.
What kind of damage/lesions result in deficits in motor learning?
Basal ganglia disease, cerebellar lesions
Why does the horizontal tilt show greater BOLD signaling (in V1) than oblique?
Because in real life we see more horizontal straight stuff than oblique tilts. However, after learning, the
Brain Lesion in Case H.M.
Bilateral resection of medial part of temporal lobe (hippocampus, amygdala, surrounding cortices) Lateral part of temporal lobe was intact Learned: The medial temporal lobe is critical for memory-specifically the hippocampus and surrounding medial temporal lobe cortices There are multiple forms of memory, with the medial temporal lobe supporting declarative memory The medial temporal lobe system has a time-limited role in memory
Where are the recurrent collaterals in the hippocampus?
CA3
What lesions result in performance failure of win-stay tasks?
Caudate nucleus lesions (specifically the dorsolateral part of the striatum = putamen) impair performance on win-stay (but not win-shift) Hippocampal lesions will not result in any performance deficits. However performance is insensitive to devaluation
What are place fields in the hippocampus?
Cell that will fire only in relation to a rat/ human being oriented in a specific location in space (does not fire when it is not in that location)
What are the 2 types of consolidation?
Cellular Plastic changes require gene transcription and translation - as these take time (hours) Systems level Remote memories are insensitive to hippocampal (or medial temporal lobe) lesions - the neural representation of memory changes - this takes place over a long time frame (knowing a route you used to walk a lot)
What area is responsible for freezing?
Central Gray (midbrain) / periaqueductal gray?
What causes the triggering the freezing and autonomic response, and hormones to be released?
Central Nucleus
Where does information in the basolateral group travel to in the amygdala?
Central Nucleus
Working Memory Encoding Diagram
Central executive - controls what goes in and not into your working memory Working memory can be verbal storage or spatial storage (can fill both of these; they don't interfere) Encoding=arrows coming down into declarative memory Retrieval = upward arrows; putting it into working memory
Results of the concurrent discrimination learning in amnesic pts
Control: Can learn nearly perfectly and can use the info flexibly EP amnesiacs area able to learn over time (even weeks later) which gives the reward, but cannot use knowledge of pairs flexibly learned to pick the right object in each pair out of habit, rather than because they remember which items had been rewarded before
Differences between controlled vs automatic attention
Controlled: Attention can be directed voluntarily to a certain location Automatic: Attention can also be grabbed involuntarily by salient stimuli
Medial Temporal Lobe Memory System
Cortical regions surrounding hippocampus receive highly processed information from association cortex Entorhinal cortex also projects to hippocampus CA3 and CA1 (major input); also to the dentate gyrus of the hippocampus via the perforant path Output of the hippocampus is subiculum to entorhinal cortex
Who was Jon?
Developmental amnesic patient - sustained an anoxic period at birth resulting in a reduction of about 50% of hippocampal tissue >> hippocampus might be particularly sensitive to oxygen loss because affects NMDA receptors that lead to cytotoxicity -otherwise fairly normal brain -vocab and semantic knowledge within normal range -struggled with episodic memory
Startle Pathway (6)
Ear -> Ventral cochlear nucleus -> Ventral nucleus of the lateral lemniscus -> Nucleus reticularis pontis caudalis -> spinal cord motor neurons -> muscles
Difference between egocentric and allocentric
Egocentric= relative to the rat's position (e.g. cell fires when rat is facing the fish about a centimeter from the fish, regardless of where the rat is in the box) Allocentric= relative to the location in space- upper left corner of box, regardless of whether the toy is in front or behind
What are the direct and indirect circuits for motor skill learning/ movement initiation?
Direct circuit: Str-> GPi -> Thal -> Cortex (double inhibition = excitatory) Indirect circuit: Str-> GPe-> STN ->GPi-> Thal->Cortex (triple inhibition)
Functions of the ventral stream and dorsal stream
Dorsal stream terminates in the posterior parietal lobe - involved in how to interact with objects (not as consciously aware) Ventral stream terminates in the inferior temporal lobe - used for identifying what you are seeing (being consciously aware) Occipital lobe -> superior and inferior longitudinal fasiculi
What lesion to which area prevents rats from developing the habit response (body turn)?
Dorsomedial caudate nucleus
Late vs. early selection models
Early selection model: the attention processing gets bottlenecked at the awareness level and only what you are focused on is semantically analyzed. Late selection model: things are getting fully processed but it never gets fully sent to your awareness
Which areas correlated with the single test and the dual test conditions?
Dual test = putamen Single test = Hippocampus Flexibility test = very strongly hippocampus
How might we manipulate memory system engagement in humans?
Dual-task conditions (ie distractions) at encoding reduce declarative memory, which might affect the MTL engagement in classification learning. (Dual is when you count tones - when you do the same weather task tell us if it'll be sunny or cloudy the dual people will take longer to predict weather) Using fMRI, we can see whether learning is dependent on the neostriatum when people are learning under distraction (when MTL is impaired)
What evidence supports early selection models?
ERP (evoked response potential) ERPs to attended vs. unattended stimuli start to reliably separate after about 100 msec (this is pretty early). This timing suggests that unattended information is processed less thoroughly in early sensory cortex The fact that don't separate earlier shows that they aren't separated near the ear/ auditory cortices. Which tells you that it won't know the difference between unattended and attended info..
How does Working Memory and Executive Control work in terms of encoding memories?
Encoding declarative memories relies on information transferred from working memory to long term memory. By controlling what is in working memory, we can make learning more effective We can also exert executive control over retrieval - using strategies, inhibiting interfering information, monitoring to make sure what you come up with is appropriate
Endogenous vs. Exogenous cues
Endogenous cue = cue is there and you have to attenuate to it Exogenous cues = cues that are out there that will grab your attention automatically
As mice continue to practice the rotorod, engagement of which parts of the brain move to which area?
Engagement of Dorsomedial (caudate) moves to the Dorsolateral (putamen) striatum. This change happens when the mice just starts to get the hang of the modulation up until it becomes easy. dorsomedial striatum had a lot more sensitivity and changed their firing a lot (Humans: moves from a more cognitive caudate prefrontal loop to a motor primary motor cortex putamen loop)
What is the difference between episodic and non-episodic memory?
Episodic memory is a person's unique memory of a specific event, so it will be different from someone else's recollection of the same experience.
Gaze Direction cues in the Posner Paradigm (eyes on a cartoon face). Is this an endogenous or exogenous cue?
Exogenous Why though?
Where is the earliest level where you see attention effects?
Extrastriate cortex seemed to be earliest level where you see attention effects
What facial parts can trigger the lateral amygdala?
Fearful face/ eyes -Left Hemisphere: there was a specific activation for the fear eyes
How is fear conditioning measured?
Freezing & fear-potentiated startle response (jumping)
Is the hippocampus involved in highlighting differences among similar things (making episodic memories unique)?
HYPOTHESIS: There is a decrease in BOLD signal when the item is repeated, so if the close lure does not decrease, the system is treating it as a new item Left entorhinal - reduction when repeated but similar reduction with similar item (another duck, doesn't care, treats it as same even if slightly different) Parahippocampal cortex - increase during repetition Subiculum and CA1 region did not show increase in lure really Role of CA3/Dentate region = orthogonalize; separating out similar memory traces
How many seconds does the high road and low road take?
High road = 30-40 ms Low road = 12 ms
What lesions prevent rats from learning place response but not habit response?
Hippocampal lesions They will not be able to find the reward, but given enough overtraining, rats will develop a turn habit response.
Win-shift strategy learning depends on what area?
Hippocampus
What brain region plays a specific role in episodic memory?
Hippocampus - surrounding cortical regions are adequate to support feelings of familiarity
Diseases that affect motor circuits
Huntington's -> problems with striatum Parkinson's -> problem with DA input Leads to motor skill deficits and motor learning deficits
Is the amygdala the ultimate site of storage of fear memories?
It is hard to tell if it is the amygdala consolidates fear memories and stores it there or if it has a time-dependent role like the hippocampus.
What were the results of the Attention Network Task?
Learning helped rahter than with no cue There were interactions between the different measures Alerting (bright bow cue)reduced reaction time overall, however, there was a bigger effect of conflict when there were alerting cues. Maybe alerting and resolving conflict occur in parallel Valid orienting (invalid) helped executive control, while having to disengage and shift attention hurt executive control These (attention and executive control) may rely on overlapping circuits
At what stage of processing does attention occur?
Late selection models say that info is all processed, but only a subset reaches consciousness Early selection models say that it occurs at the stage of perception
Where do information about a rat's location come from (which cortex)?
Medial Entorhinal Cortex
What area of the brain is needed for declarative memory in mammalian species?
Medial Temporal Lobe
What is perceptual learning?
Learning to perceive better/ discriminate between very similar stimuli. Ex: how an expert can discriminate sonar patterns and x-rays very well
Patients have memory deficits but have an intact hippocampus. What is wrong?
Lesions to the frontal lobes -recall is much worse than recognition -they have trouble with remembering the temporal order of events -they sometimes confabulate because of poor cognitive control -not lying but is very difficult to distinguish between your own memory and other details (from movies, etc).
What is the potentiation of startle in the experiment?
Light(conditioned by shock) + loud sound = augmented startle i.e. potentiation of startle when making loud noise right after watching a scary movie
Cortico-Striatal Loops involved in motor skill learning diagram
Loop and motifs are replicated many times throughout the brain, where different inputs from the cortex goes to different areas to the striatum.
Practicing a motor skill can result in increased activity in what area?
M1 (primary motor cortex) -this activity can be specific to a sequence, not just movements
What are the differences between the medial and lateral aspect of the entorhinal cortex?
MEC cells process spatial information (not as much as in CA1). Many will fire depending on the location of the rat, and many also are sensitive to the head direction of the rat. its position relative to the object does not matter. LEC doesn't care where animal is; cells do not generally fire when the rat is in a specific location. However, some cells in this area can fire in an egocentric manner in relation to an object. the LEC fires when the rat is facing the toy fish from a certain distance. It doesnt matter where the rat is in the box, it is coding where the rat is relative to the fish. parasubiculum is a bit more spatial but perirhinal is not at all. LEC but not MEC cells show egocentric bearing tuning of 3D objects -Need to combine all of these together for episodic memory
What does MEG (Magnetoencephalography) show?
MEG technique shows evidence of sensitivity to attention in V1 Time courses are faster than 100 msec, so thus not feedback MEG more sensitive to synchrony than recording from single units Neurons aren't just firing more but are firing more in sync with each other?
Working Memory - difference between maintenance and manipulation?
Maintenance =holding information in mind-keeping irrelevant information out Manipulation = doing something with the contents of working memory-needed for strategizing and decision making -(activating dorsal lateral prefrontal cortex)
Amnesia can result from lesions to midline diencephalic nuclei. What areas specifically are damaged?
Mammillary bodies Anterior thalamic nuclei
How is habit learning in humans different with rat learning?
Many of the tasks that are learned as habits by rats would be learned declaratively by humans one way to get around that is probabilistic associations where the stimuli are probabilistically associated with outcomes so the memory for one specific event is not as helpful. Ex: Weather prediction task
How can the mere exposure effect and why you like things you are pre exposed to be explained in neuronally?
May be like Priming-increase perceputal fluency. Because less resources are needed for processing pre-exposed materials in the sensory cortex, it may stand out to you and you may interpret this as to liking them a bit better. It is only after the fact that you may make up a reason why you liked the pre-exposed stimulus.
Preference Learning
Mere exposure effect - previous exposure to a stimulus leads to preference for it Mere Exposure Effect works not just visually but also audio-ly i.e. with amnesiacs couldn't remember the people they met 300 times but did have better rapport.
Alternatives to Standard Systems Consolidation Theory
Multiple trace theory -all declarative memory just gets stronger and independent of hippocampus hippocampus is always needed for episodic memory -Episodic and semantic memory have a qualitative difference (With semantic memory - when you have a partial lesion like most amnesic patients a little bit of hippocampus spared, semantic memories represented in hippocampus but multiple representations over time so with semantic memory a larger lesion is needed to inhibit that memory especially for older information)
Learning depends on what kind of LTP?
NMDA-dependent LTP
Where do you see modulation effects of visual attention?
Neurons in V4 show attentional modulation Firing is greater when monkey is attending to a stimulus in receptive field than when it is not attending to the stimulus
Where is the site for augmentation of startle response in the startle pathway/ brain?
Nucleus Reticularis Pontis Caudalis
What is associative recognition?
One of the ways to assess the ability to retrieve a previously encountered association defined as distinguishing the studied association of two or more items from novel associations. This task requires remembering the specific pairing of two items (associative memory) in addition to remembering the individual items (item memory). In the previous example, we need to remember the person's face and the name individually (item memory) in addition to remembering the association between the two (associative memory). These studies tell us if the brain substrates for episodic memory differ from those from non-episodic memory
Deep and Shallow tests of Memory Learning
PURPOSE looking for processes/ areas of the brain that were used for encoding memory FOUND the biggest difference was in the left prefrontal cortex You are able to find much more activity/ blood flow in the prefrontal regions during deep processing
Diencephalic and parahippocampal projections
Parahippocampal region important to know, hippocampus All green (MTL system) Fornix to anterior thalamic nuclei
What are the evidence for a specific role of the hippocampus in episodic memory?
Patients with selective hippocampal lesions seem to be able to learn facts (case of Jon), but have poor episodic memory Neuroimaging studies show hippocampal activation for recollection or associative recognition
Neural locus of perceptual learning
Perceptual learning can be specific to a visual quadrant or to one eye Occipital lobe is V1 retinotopic meaning that this type of perceptual learning may occur in early visual regions where the neurons that are driven primarily by one eye, or specific retinal position (V1 or V2 in Occipital lobe)
Hippocampal Subregion Projections
Perirhinal projects to lateral entorhinal Parahippocampal projects to medial entorhinal Big projection from Entorhinal cortex is to DG in hippocampus
What is the neural Basis of Priming
Priming tends to be accompanied by a DECREASE in fMRI signal in cortical areas that support perception AKA "Repetition Suppression"
What is the Rotorod Test?
Put rats on the rotorod and have them modulate their speed as to not fall off This particular task is pretty sensitive; as animals train on it, they become much more stable and will get the speed and balance more precise to stay on Another method of motor skill learning/ adaptation The corticostriatal loop that is being engaged moves from cognitive caudate/prefrontal loop (learning) to motor/putamen loop (well-learned)
What is the importance of oscillations in brain function?
Rate of firing of neurons may not be the main way that the brain communicates or represents information. that frequency of oscillations across regions are more developing. Importance of brain rhythms (like in sleep).
As you go further along in ventral streams, what happens to the receptive fields?
Receptive Fields get bigger. Early visual regions = receptive fields are very small and specific, and as you get further along like in the temporal lobe, the receptive fields are larger.
EXP measuring episodic memory in the lab
Remember/Know Task - ask subjects to introspect about their memory -Many words on a list and ask subject to tell experimenters which words they recognize Can they relive the moment they saw that word or does it just look really familiar? Remember = episodic; know = non-episodic (semantic) Ask subjects about source memory Ask them about the moment that learning occurred - do they remember the background color of the list where the words were shown episodic memories have incidental details bound to them Suggests that the person does have episodic memory
What is a characteristic of Declarative Memory Retrieval (Jean Piaget)?
Retrieval is reconstructive- not a completely accurate replaying of a memory- it can be influenced by reinterpretation of events or blend similar instances
What is the difference between semantic memory and episodic memory?
Semantic Memory -memory for facts -disconnected from the moment of learning -Shared across people -Appears to depend on medial temporal lob for learning but not hippocampus Episodic Memory -memory for events -memory is tied to a specific time and place -memory is from your own perspective -Can remember incidental details -Appears to specifically depend on hippocampus for learning
EXP Retrieval-Induced Forgetting in the Lab
Set-up: Subjects study categorized lists: (orange, peach, lemon, pear.... Maple, oak, birch, etc.) Subjects then practice retrieving some of the items from some of the categories (Fruit-o__?) During the test, they are asked to recall all the items from all the categories. Results: #1: Subjects recall best things that were practiced #2 Items from unpracticed categories #3 Subjects had the most difficult with unpracticed items from categories they had practiced (competitive)
When you get good at a skill you will have a decrease in activation. Why?
Skilled movement will lead to more efficient representation of the skill (only using what you need to perform that skill). This is contrary to what the figure says because this is in the context of more complex systems whereas for the figure, more simple tasks like the finger tapping tasks will recruit more neurons in anticipation of movement from the sequence. This is different for the complex movements like a tennis player learning to do the movement more efficiently
Preference Learning experimentation set up
Stimuli used are typically those that are unfamiliar to subject so they don't have pre-existing preferences Subjects are not necessarily aware of why they have the preference- can occur with subliminal presentations i.e. showing pairs abstract paintings and asking what you like better i.e. Amnesic patients and Korean melodies
Habit learning is characterized by what kind of associations?
Stimulus response associations which is in contrast to action-outcome associations (purposeful motivatory actions) Ex: following a familiar route
Green line task
Subjects fixated on center Green line pointed to circle to be attended Circles jiggled and flickered during delay When tone came on, subject indicated if the circle was present our not
What is the Serial Reaction Time Task?
Subjects simply press a button corresponding to the position of a cue on the screen. Unbeknownst to the subject, on some of the blocks the stimulus moves according to a complex sequence Even though subjects might feel like the reaction time task is random, it will have a specific sequence in which over time they will learn to do faster. Your brain is sensitive to this sequence
What does reduction of activity in cortical areas mean?
Suggests that second time you see it, there is more efficiency of work/ circuitry. Reflects of behavioral priming Other suggestions include that there is TUNING involved. Neurons that are specifically involved increase firing whereas the ones that aren't decrease firing, which creates a net decrease in neuronal noise. (Can't assess with BOLD signal)
Visual Priming is associated by which cortical areas? (Perceptual identification and fragment completion)
Supported by sensory cortical areas in the occipital lobe. As you see it more there is reduction. Demonstrates a gradient of stimulus specificity that decreases as you go from the posterior (highest) to anterior (lowest) regions.
krovitz method
Takes a noun and give a specific event from your life (attached to a time and place) that corresponds with that verb finds that patients describe episodic memories from childhood and not really any recent ones (they aren't able to remember the more recent ones) evidence that episodic memories may consolidate
What does the ANT task separate out?
The ANT task separates alerting from orienting Also, you can have a double cue or no cue in addition to a cue to one location Like the Posner task, but rather than a dot appearing, arrows (either congruent or incongruent) appear and you have to indicate the direction of the center arrow filter out the interference
Is the amygdala involved in semantic and episodic memory?
The amygdala is not necessary for semantic or episodic memory. It does appear that activation of the amygdala can strengthen these memories, though, as emotional content enhances memories.
Why is the associative recognition task a test for episodic memory and not non declarative memory?
The associative recognition task is a measure of episodic memory because you cant just remember that each item looks familiar but that they were presented together- so you have to go back to the event when they were presented.
What part of the brain does contextual fear depend on?
The hippocampus
If you lesion the dorsolateral striatum, what happens in rat behavior?
The rats will produce a correct "place response" but will fail to develop the habit turn response from overtraining
What doe the Ebbinghaus and Ponzo illusions tell us about the ventral and dorsal stream?
The ventral stream will take into context where the object is and will manipulate it/make a perception to seem like it looks bigger/ smaller than it actually is. However, the dorsal stream will not be tricked. (Picking up the blue dots but the finger aperature will not change for each)
How does the weather forecasting test assess motor skill/ stimulus-response habits (procedural memory)?
The weather prediction task does not measure motor skill, it seems to measure something more like stimulus-response habits. The probabilistic nature of the associations makes them hard to memorize, so people can gradually learn to make the most associated response when the cues are presented even though they think they are just guessing. The textbook also has a good description of this task
When rats are overtrained in the cross maze task, what happens with their habit learning?
There is an increase in responding based on motor response and not on place response The rats being trained will go towards food/reward based on spatial recognition of where it is, but overtraining will result in the rat turning right (which is the wrong direction in the second model)
What is the difference between autobiographical interviews and the krovitz test?
These are two different tests. The autobiographical Interview specifically asks the subject about personal life events that they experienced, such as trips, weddings, etc. You need to find friends or relatives to make up a list of such events. The Krovitz test uses word cues (e.g. apple, star, etc. )and the subject has to come up with an episodic memory that is retrieved by that cue.
Attention Network Task
This task is designed to separate out the effects of 3 processe:s 1,Alerting, general arousal 2.Orienting, directing attention to a location or object based on automatic or controlled attention 3.Executive control- resolving conflict- paying attention to something when there is a distraction, filtering
What is Magnetoencephalography?
This technique allows for good temporal and spatial resolution suggests that you can see changes early in V1 Instead of electrical signal in EEG, it is looking at magnetic signals
3rd type of nondeclarative memory: Conditioned Emotions
Through conditioning, stimuli can elicit emotional reactions (fear).
Perceptual Learning in the Lab
Tilt Discriminations - can start to see subtle differences in the tilt over thousands of trials Vernier Gap -be able to say which line is to the left or right of a gap as it gets closer Real Life: wine experts
Perceptual learning -> increase in BOLD activity. Priming -> decrease in BOLD activity after repetition. Why is this the case?
Time course is different for both: Priming: the second time you see the stimulus, the neuronal activity is reduced. Perceptual learning: huge time difference. Remodeling synapses and recruiting neurons to do things they didn't do before and the way blood flow changes is different.
What kind of manipulation can you do with mice instead of rats in other model?
Transgenic Mice
Is working memory strictly declarative? If there are 2 divides (1 declarative and 1 non declarative), are both finite?
When we talk about declarative vs. nondeclarative memory, we think of those as distinctions within long-term memory, while working memory is not long term. You are definitely aware of the contents of working memory, but this information does not necessarily become part of long term storage unless it is encoded.
Desimone studies of attentional modulation in V4
When attention is directed to a location in the visual attention is directed to a single stimulus sensitivity to stimuli at that location is increased.
What is the high road and low road of fear processing?
You see a dangerous stimulus (snake) that you later perceive as safe (rope) and will activate first the low road pathway (sensory thalamus straight to the amygdala to exhibit fear response) but then will trigger afterwards the high road processes which shows input from the sensory cortex (understanding why something is a danger) to your amygdala.
EXP Subsequent Memory Effect
defined as significantly greater activation of a particular brain region during memory encoding for trials in which later retrieval was successful compared to that in trials in which later retrieval was unsuccessful. Better retrieval = more activation of brain (fMRI)
Difference between the purpose of the Remember/Know Test, Associative Recognition, Source Memory . vs. Autobio interview, Krovitz method
first three methods are for measuring episodic memory in the lab- lets say I have the hypothesis that a certain subregion of the hippocampus will be active when you are forming episodic memories, or I have an hypothesis that distraction during retrieval will affect episodic memory specifically, etc. I would use these tasks in the lab. The other tasks are looking at episodic memory from your past- not memories we try to create in the lab. So if I want to assess retrograde amnesia in a patient to see how far back it goes, I would use these tests. Or if I have the hypothesis that childhood episodic memories are different than episodic memories acquired during adulthood, I might use these tasks
What is an example of unconscious cognitive processes in visual perception?
functions of the dorsal stream in vision (projections coming from the occipital cortex to the posterior parietal lobe = postrhinal/ parahippocampal gyrus) We are aware of the outcome of ventral stream processing (Perirhinal cortex = temporal lobe), dorsal stream processing operates outside awareness to shape visuomotor behavior
ERP experiments can't be replicated with fRMIs. Why?
fMRI time lag is too long and the timing of when attenuated and unattenuated stimuli response is the evidence for the early selection model
What is semantic memory?
facts and general knowledge
What does executive control activate?
frontal lobe = anterior cingulate, lateral prefrontal, parietal (fronto-parietal control system)
What is the posner cueing task
measures benefits of covert attention on detection (valid trial) and the cost of disengaging attention (invalid trial) -it's too fast to move eyes and measures overt attention We can also look at controlled vs. automatic attention with endogenous vs. exogenous cues
Weather prediction task results
older adults adn amnesic pts learn to gradually associate the cues with the correct responses They improve, even if they feel they are just guessing and aren't able to use their knowledge in a flexible way Young subjects with good declarative memory abilities can perform the task to some extent Pts with Parkinson's and Huntington's disease are imparied
What is source memory?
recall of when, where, and how information was acquired; remember incidental details surrounding the memory
What is Urbach-Wiethe disease?
recessive genetic disorder that includes development of bilateral calcification of the amygdala. Patients don't seem to express fear. But can be aware of what is negative.
Perceptual learning = increases of BOLD signal after protracted training. What happens after repetition?
reduced BOLD signal Priming -> 1st exposure = activation - 2nd exposure = faster/ more efficient activation Perceptual Learning = Modifications and increasing the # of cells that are doing a particular job
Entrainment of oscillations to attended stimuli
rhythmic attended stimuli (like metronome) can entrain/ line up your oscillations Perhaps you are able to focus on the specific frequency of the sounds you want to pay attention to, even if it isn't the largest amplitude sound