Psych 313 Final
priming
A change in response to a stimulus caused by the previous presentation of the same or a similar stimulus. priming can occur even when there is little explicit memory for the words. Rosch (1975b) "Priming" • Does prototypicality affect priming? • Task: 1. Hear a color word 2. Make a same/different judgment about two colored discs Rosch (1975b) "Priming" • Conclusion: When participants heard "green" they brought to mind the prototype for the color green. This acted as a better prime for stimuli that matched the prototype well.
Korsakoff's syndrome
A condition caused by prolonged vitamin B1 deficiency that leads to destruction of area on the frontal and temporal lobes and causes severe impairments in memory.
systems consolidation
A consolidation process that involves the gradual reorganization of circuits within brain regions and take place on a long time scale, lasting weeks, months, or even years.
spreading activation
Activity that spreads out along any link to a semantic network that is connected to an activated node.
Processes of Long‐Term Memory (LTM)
Primarily for explicit/declarative/conscious memory (episodic and semantic): • Encoding - Storing information into LTM • Retrieval - Bringing information in LTM back into consciousness Levels of Processing Theory • Which task causes deeper processing? - Using a word in a sentence - Deciding how useful an object might be on a desert island • We test memory in each condition - Conclude that stronger memory must have been caused by deeper processing • But depth of processing has not been defined independently of memory performance - Therefore, this is circular reasoning!
integral immediate emotions
Immediate emotion that is associated with the act of making a decision.
Explicit versus Implicit memory
Implicit memory - Unconscious (not available to awareness) - Non‐declarative (not easily described in words) - Sub‐types: • Procedural memory: skills • Priming: change in response due to previous presentation • Classical conditioning: e.g. Pavlov's dog Explicit memory - Conscious - Declarative - Sub‐types: • Episodic: personal events/episodes • Semantic: facts, knowledge
pragmatic reasoning schema
Inference that occurs when reading or hearing a statement that leads a person to expect something that is not explicitly stated or applied by the statement
pragmatic inference
Influence that occurs when reading or hearing a statement leads a person to expect something that is not explicitly stated or necessarily implied by the statement.
explicit memory
Memory that involves conscious recollections of events or facts that we have learned in the past. aka declarative or conscious memory
implicit memory
Memory that occurs when an experience affects a person's behavior even though the person is not aware that he or she has had the experience. aka non-declarative
misinformation effect
Misleading information presented after a person witnesses an event can change how the person describes that event later.
typicality effect
More typical members of a category are processed faster and easier "An apple is a fruit." versus "A pomegranate is a fruit." Exemplar approach explains typicality effect: • The more similar an object is to known category members (exemplars), the faster it will be categorized. • The more exemplars an object is similar to, the faster it will be categorized.
ultimatum game
Offered to split a certain amount of money between 2 people. If the responder agrees they get the split if they reject no one gets anything. the right anterior insula was 3 times more activated when responders rejected offers. the PFC is more concerned about the act of obtaining money.
Hierarchical Organization
Organization of categories in which larger more general categories are divided into smaller, more specific categories. These smaller categories can in turn be divided into even more specific categories to create a number of levels. • This represents "IS A" relationships - E.g. a g truck IS A vehicle; a pickup IS A truck • How are other relationships represented? - E.g. a truck HAS wheels; a vehicle CAN move
misleading postevent information (MPI)
The misleading information that causes the misinformation effect.
state-dependent learning
The principle that memory is best when a person is in the same state for encoding and retrieval.
encoding specificity
The principle that we learn info together with its context. This means the presence of the context can lead to enhanced memory for the info Retrieval is more successful when the context at encoding matches the context at retrieval State‐Dependent Learning • Learning is associated with a particular internal state Eich & Metcalfe (1989) • Used happy or sad music to induce a mood before studying Better memory if person's mood at encoding matches mood during retrieval
conjunction rule
The probability of the conjunction of 2 events (such as a feminist banker) cannot be higher than a single descriptor (like a banker)
representativeness heuristic
The probability that an Event A comes from class B can be determined by how well A resembles properties of class B.
encoding
The process of acquiring information and transferring it into memory
retrieval
The process of remembering information that has been stored in long-term memory
consolidation
The process that transforms new memories into a state in which they are more resistant to disruption. • Transforms new memories from fragile state to more permanent state • Involves gradual reorganization of circuits in brain
falsification principal
The reasoning principle that to test a rule, it is necessary to look for situations that would falsify the rule.
omission bias
The tendency to do nothing to avoid having to make a decision that could be interpreted as causing harm.
confirmation bias
The tendency to look for info that conforms to our hypothesis and to overlook info that does not agree with it.
Semantic Network approach
This approach to understanding how concepts are organized in the mind that proposes that concepts are arranged in networks. Collins & Quillian (1969) • Node = category/concept • Links between nodes represent "IS A" relationships • Nodes are also linked to properties • Links between nodes and properties represent other relationships Collins & Quillian (1969) • Cognitive economy Shared properties are only stored at higher‐level nodes • Inheritance Lower‐level items share properties of higher‐level items (e.g. a robin has feathers) Collins & Quillian (1969) Prediction: The time it takes to retrieve information about a concept should depend on the distance in the network. Shorter = faster. Sentence verification task: Respond "yes" or "no" is a sentence true. Meyer & Schvaneveldt (1971) Prediction: Spreading activation - When a concept is retrieved, activity should spread out from the node along all links. - An active node should then be "primed," making it easier to retrieve from memory. Problems for Collins & Quillian semantic network 1. Cannot explain typicality effects An apple is a fruit. A pomegranate is a fruit. Apple and pomegranate are equidistant from fruit in the Collins & Quillian network. Problems for Collins & Quillian semantic network 2. Cannot explain inverted distance effect: Rips, et al. (1973) Sentence verification task: A pig is a mammal. RT = 1,476 ms A pig is an animal. RT = 1,268 ms Pig is closer to mammal than animal, so mammal should be faster. Collins & Loftus (1975) Updated semantic network model: 1. Links can be shorter or longer • Shorter = more closely related • Longer = less closely related E.g. apple‐fruit link is shorter than pomegranate‐fruit link Explains typicality effects: shorter links lead to faster response times 2. No strict hierarchical structure • Any two concepts can be linked E.g. pig‐mammal link and pig‐animal link Explains inverted distance effects: connections do not need to follow the hierarchy 3. Existence and strength of links depend on individual experience Collins & Loftus (1975) 1. Links can be shorter or longer 2. No strict hierarchical structure 3. Existence and strength of links depend on individual experience Lack of falsifiability - Any relationship between concepts can be represented - No rules for determining link existence or length - Circular reasoning... - Therefore, there is no experiment that would "prove it wrong" How to move the science forward? - Create computer models of how people learn semantic relationships from experience - Study learning of semantic categories and relationships during development - Look at how categories and their relationships are represented in the brain
amygdala
a sub-cortical structure that is involved in processing emotional aspects of experience. activity was higher for emotional words
mental time travel
according to Tulving, the defining property of the experience of episodic memory. a person travels back in time in his or her mind to reexperience events that happened in the past.
specific level
aka subordinate level. The level in Rosch's categorization scheme that is the level below the basic level.
global level
aka superordinate level. The highest level in Rosch's categorization scheme. ex. furniture or vehicles.
long-term memory
covers a span from about 30 seconds ago to your earliest memories. Semantic coding is the predominant type of coding in LTM. Brady et al. (2008) • Study Phase: -Presented 2500 images for 3 seconds each -10 blocks of 20 minutes, with 5 minute breaks = ~4 hours in total • Test Phase: -Began after a 10 minute break -300 test trials... Brady et al. (2008) • Tested memory using three increasingly similar types of foils in 2‐alternative forced choice: Capacity: Brady et al (2008) • Memory was remarkably good in all three conditions!
deductive vs. inductive reasoning
deductive-something is true or false. inductive- something is probably true.
self-reference effect
ppl are more likely to remember words that describe them.
shallow processing vs. deep processing
shallow is processing that involves repetition with little attention to meaning. and deep is deeeeep.
Prospect Theory
- People do not make decisions based on expected values, probabilities, and final outcomes. - People make decisions based on subjective utility, decision weights, and relative outcomes. • People transform objective value into subjective utility • Diminishing marginal utility - Subjective value increases more slowly than objective value, especially at large values - $10 is subjectively worth twice as much as $5, but $10,000,000 is not subjectively worth twice as much as $5,000,000. • Individual differences: Bill Gates versus me • People transform objective value into subjective utility • Loss aversion - Losses loom larger than gains - Losing $20 g feels worse than winning $20 feels good • Individual differences in sensitivity to loss • People transform objective probability into subjective decision weights • Small probabilities (but greater than 0%) are overweighted - 1% feels like much more than 0% - 51% feels about the same as 50% • Large probabilities (but less than 100%) are underweighted - 99% feels like a lot less than 100% - 50% feels about the same as 51%
cognitive economy
A feature of some semantic network models in which properties of a category that are shared by many members of a category are stored at a higher level node in the network. For example, the property "can fly" would be stored at the node fro "bird" rather than at the node for canary."
paired-associate learning
A learning task in which participants are first presented with a pair of words, then one word of each pair is presented and the task is to recall the other word.
repeated reproduction
A method of measuring memory in which a person reproduces a stimulus on repeated occasions so their memory is tested at longer and longer intervals after the original presentation of the material to be remembered. War of the Ghosts experiment- the story represented more of their own culture than the culture in the story.
connectionism
A network model of mental operation that proposes that concepts are represented in networks that are modeled after neural networks. Aka parallel distributed processing (PDP)
schema
A person's knowledge about what is involved in a particular experience.
permission schema
A pragmatic reasoning schema tat states that in a person satisfies condition A then they get to carry out B. Has been used to explain the results of the Watson card task.
synaptic consolidation
A process of consolidation that involves structural changes at synapses that happen rapidly, over a period of minutes.
reconsoldidation
A process proposed by Nader that occurs when a memory is reactivated. It occurs right after initial learning but is apparently faster than consolidation. when a memory is retrieved, it is apparently reformed, and is once again subject to interference Nader et al. (2000) - Fear conditioning in rats • Condition 1: memory preserved. rat learns to fear tone, inject anisomycin, rat freezes in response to tone Nader et al. (2000) - Fear conditioning in rats • Condition 2: memory formation blocked. inject anisomycin before consolidation, day 2 nothing, day 3 rat does not freeze after tone. Condition 3: memory reconsolidation blocked. rat learn to fear tone, day 2 rat freezes to tone then inject anisomycin reactivation (inject during reactivation, day 3 rat does not freeze. Nader et al. (2000) - Fear conditioning in rats • In Condition 3, memory formation is blocked when the memory is recalled/reactivated, and this causes the memory to be forgotten! • Reconsolidation occurs after recall, and this is blocked in Condition 3
reactivation
A process that occurs during memory consolidation in which the hippocampus replays the neural activity associated with a memory. During reactivation, activity occurs in the network connection the hippocampus and the cortex. The activity results in the formation of connections between the cortical areas.
script
A type of schema. The conception of the sequence of actions that describe a particular activity. For example, the sequence of events that are associated with going to class would be a "going to class" script.
anterograde amnesia
Amnesia for events that occur after an injury- that is, the inability to form new memories.
medial temporal lobe (MTL)
An area in the temporal lobe that consists of the hippocampus and a number of surrounding structures. Damage to MTL can result problems forming new long-term memories. hippocampus is important as well. the activity in the perirhinal cortex was greater for the remembered words than for the forgotten words. the parahippocampal area is important for remembering spatial information. the enthorhindal is important with recognition memory. amygdala- emotional memory.
cognitive hypothesis
An explanation for the reminiscence bump, which states that memories are better for adolescence and early childhood because encoding is better during periods of rapid change that are followed by stability.
post-identification feedback effect
An increase in confidence of memory recall due to confirming feedback after making an identification. This effect can occur after a person identifies someone in a lineup.
The Constructive Nature of Memory
Bartlett's (1932) "War of the Ghosts" • Had participants (British) attempt to remember a folk story from a different culture (Canadian First Nations) • Repeated reproduction • Results - Over time, reproduction became shorter, contained omissions and inaccuracies - Changed to make the story more consistent with their own culture, e.g. "canoes" became "boats" • Two sources of information: story & past experience • Source memory: - Process of determining origins of our memories • Source monitoring error: - Misidentifying source of memory - Also called "source misattributions" • Errors in Bartlett's study can be interpreted as inability to separate memories from story with memories from other experiences • Sharing a story with someone, only to discovery they were the one who told it to you... • Pragmatic inferences - Based on knowledge gained through experience
availability heuristic
Basing judgements of the frequency of events on what events come to mind.
difference between cognitive psychology and cognitive neuroscience
Cognitive Psychology The scientific study of how people perceive, learn, remember and think about information. Cognitive Neuroscience The scientific study of how the brain mediates cognition and behavior by relating neural structures to mental functions.
retrieval cue
Cues that help a person remember info that is stored in memory.
Long‐Term Memory & Brain areas
Davachi et al. (2003) • Study phase: - While in fMRI - Presented 200 words - Associate image with each word • Test phase: - Presented 200 new words & 200 old words - Recognition test - respond new/old for each Davachi et al. (2003) • Analysis: Look at brain activation at encoding as a function of success during retrieval -percentage change in brain activities is higher in perirhinal cortex for recognized words than forgotten words. in hippocampus recognized and forgotten is the same. Success at retrieval predicted by perirhinal cortex activation at encoding.
framing effect
Decisions are influenced by how choices are stated. - People make decisions based on gains and losses relative to a point of reference, not based on the absolute final outcome. - Changing the way a question is asked to create a different point of reference leads to different choices.
CogLab: False Memory
Deese (1959), Roediger & McDermott (1995) • DRM paradigm • Presented list of semantically related words: Bed, rest, awake, tired, dream, blanket, doze... • Recognition memory test: - Words on list (rest, tired, dream) - Unrelated distractors (cake, mountain, cloth) - Semantically‐related distractors (sleep) -our class as well as global is pretty much the same odds that they will report the related distractor as in list words. unrelated distractors are very unlikely • Related distractors reported almost as often as words actually on the list! • High confidence in accuracy • Participants often report specifically remembering the presentation of these distractors • Happens even if you know about the effect!
graceful degradation
Disruption of performance due to damage to a system that occurs only gradually as parts of the system are damaged. This occurs in some cases of brain damage and also when parts of a connectionist network are damaged.
immediate emotions
Emotion that is experienced at the time a decision is being made.
Testing effect
Enhanced performance on a memory test caused by being tested on the material to be remembered. • Roediger and Karpicke (2006) • Which results in a stronger memory trace? - Re‐reading material, or - Being tested on the material • First, participants read a passage and then either - Recall as much as they could - Reread the passage • Then, tested on recall after a delay rereading and retest did pretty much the same with 5 minute delay but when there was a 2 day or a week delay the retest group did much better
Categories in the Brain
Evidence of categorization by single neurons? Freedman et al. (2003) • Monkeys trained to categorize ambiguous stimuli as "dog" or "cat": Evidence of categorization by single neurons? Freedman et al. (2003) • Task: delayed match to sample - Trained until correct 90% of time for 60% stimuli Evidence of categorization by single neurons? Freedman et al. (2003) • Recorded from inferior temporal lobe (IT) and prefrontal cortex (PFC) • Conclusion: - There are individual neurons that help distinguish between categories - Different neurons involved in representing categories during different stages of processing (e.g. perception versus working memory) How are concepts distributed in the brain? Martin et al. (1996) • Compared brain activations (PET) for tools, animals, and nonsense objects • Task: name the pictured item How are concepts distributed in the brain? Martin et al. (1996) Objects > nonsense objects Found distributed network across many parts of the brain. Animals > tools More activation in visual processing areas in occipital lobe. Tools > animals More activation in motor planning areas in frontal lobe. - Concepts seem to be represented in part based on salient properties (e.g. uses for tools and appearance for animals). - Similar concepts represented by similar brain areas (e.g. occipital lobe for animals, frontal lobe for tools). Are the relationships between concepts the basic neural building blocks of meaning? Mitchell et al. (2008) 1. Find verbs that co‐occur with nouns based on text analysis 2. Determine brain activation for each verb 3. Predict activation for nouns as summation of activation for related verbs 4. Test predictions... • Conclusions - Concepts are represented by highly distributed patterns of activation across the brain - The relationship between concepts (as measured by co‐occurrence of words) can be used to predict brain activation for those concepts - Perceptual and motor brain areas involved in representing meaning
CogLab: Decision Making
Examples of decision making that demonstrate the tenants of Prospect Theory (Kahneman & Tversky, 1984). 5 decision‐making problems (Problem 1 - 5) 2 options for each problem (Option A & Option B) 2 versions of each problem (Set 1 & Set 2) Between‐subjects design (Some students saw Set 1, other students saw Set 2) Examples of decision making that demonstrate the tenants of Prospect Theory (Kahneman & Tversky, 1984). For each of 5 problems, there were 2 versions: -Identical absolute outcomes -With different framing of the problem and/or options -(Sometimes) led to very different patterns of choice Supports Prospect Theory over Expected Utility Theory
basic level
In Rosch's categorization scheme, the level below the global level. It is a special level because it is the level above which much info is lost and below where little can be gained. Rosch et al. (1976) • When asked to name pictures, participants tended to use the basic level category: ex pants, guitar, fish When asked to evaluate category membership, participants are faster for basic level categories: Basic level categories are maximally informative and distinctive: - maximize attributes shared within the category - minimize attributes shared between categories Tanaka and Taylor (1991) • Are the basic level categories the same for everyone? • Showed pictures of birds (and other things) to bird‐watching experts and non‐experts Basic level categories depend on experience.
recency effect
In a memory experiment in which a list of words is presented, enhanced at the end of the list. 30-second delay eliminates recency effect. recency effect is due to storage of recently presented items in STM. Murdoch (1962) • Recency effect - Memory better for stimuli presented at end - Stimuli still in STM free recall procedure: • Recency effect - Stimuli still in STM
primacy effect
In a memory experiment in which a list of words is presented, enhanced memory for words presented at the beginning of the list. primacy effect is related to the longer rehearsal time available for the earlier words on the list.Murdoch (1962) • Primacy effect - Memory better for stimuli presented at beginning - More time to rehearse, more likely to enter LTM Free recall procedure • Primacy effect - More time to rehearse, more likely to enter LTM
serial position curve
In a memory experiment in which participants are asked to recall a list of words, a plot of the percentage of participants remembering each word against the position of that word in the list.
Decision‐Making & Emotion
Iowa Gambling Task (Bechara et al., 1994) • Compared control participants and patients with damage to orbital frontal cortex Orbital frontal patients • Perform normally on IQ tests • Perform normally on tests of cognitive control (Wisconsin Card Sorting Task) • Seem to make poor decisions in life... • Compared control participants and patients with damage to orbital frontal cortex • Measured skin conductance responses (SCRs) at the time of decision making • SCRs are a measure of anxiety • "Sweaty palms • Conceptual knowledge alone did not lead to good decision making • Predictions of expected emotions were necessary for good decision making • Expected emotions preceded conceptual understanding • Patients with damage to orbital frontal cortex could not generate expected emotions • Patients overemphasized immediate reward over long‐term outcomes
CogLab: Lexical Decision
Lexical decision task • Indicate whether letter string is a word or non‐word • Stimuli presented sequentially in pairs • Independent variable: - Stimulus pair type • Dependent variable: - Reaction time (RT) on correct trials for the second stimulus in the pair Stimulus pair type Word - Associated word sand beach Word - Unassociated word bread hat Nonword - Word garsf road Word - Nonword plate naht Nonword - Nonword Prediction: If activation spreads from the first word to the associated word, then it should be primed, and RT should be faster than for the unassociated word, which won't be primed. -fastest are the actual words. fastest is the associated words second is unassociated. then nonword to word is 3rd fastest. nonword to nonword is the 2nd slowest and the slowest is word to nonword. Conclusion: Small, but consistent effect. Prediction confirmed! RT for the second word is faster when it is semantically related to the first word. This is consistent with spreading activation through a semantic network.
Retrieving Information from LTM
Long‐term memory is content addressable: • We retrieve memories based on what they are about • Not based on where they are stored in memory • Think of a phonebook: - White Pages: look people up based on where their name is in alphabetical order - Yellow Pages: look people up based on what they do • LTM retrieval works like the Yellow Pages Retrieval depends on retrieval cues: - Stimuli that help us remember information Mantyla (1986) • Self‐generated cues versus other's cues • Group 1: - Learning: See 600 nouns & generate 3 associated words for each • banana: yellow, bunches, edible - Test: See the 3 associated words, try to recall noun • Group 2: - Learning: See 600 nouns & read 3 associated words for each • banana: tropical, fruit, slippery - Test: See the 3 associated words, try to recall noun • Group 3: - No learning - Test: See 3 associated words, try to guess noun • Self‐generated cues aid recall Brain areas associated with other types of LTM • Procedural memory - Cerebellum & movement coordination - Basal ganglia & action selection • Conditioning - Amygdala & fear conditioning
remote memories
Memory for events that occurred long ago.
procedural memory
Memory for how to carry out skills. • Skill memory: memory for actions - Walking - Riding a bike - Tying a shoelace - Throwing a frisbee • No memory of where or when learned • Perform procedures without being consciously aware of how to do them • People who cannot form new LTMs can still learn new skills (e.g., H.M. & mirror drawing)
semantic memory
Memory for knowledge about the world that is not tied to any specific personal experience. Episodic and semantic memories makes up declarative memory.
generation effect
Memory for material is better when a person generates material themselves rather than passively receiving it. Generation effect • Slameka & Graf (1977) - "Read" group: Read these pairs of words: king‐crown; horse‐saddle, lamp‐shade - "Generate" group: Fill in the blank with a related word: king‐cr___; horse‐sa____, lamp‐sh___ Better memory after generation than reading.
episodic memory
Memory for specific events that have happened ti the person. Episodic and semantic memories makes up declarative memory.
flashbulb memory
Memory for the circumstances surrounding hearing about shocking events.
opt-out procedure
Procedure in which a person must take an active step to avoid a course of action. ex. choosing not to be an organ donor
opt-in procedure
Procedure in which a person must take an active step to choose a course of action. ex. being an organ donor
standard model of consolidation
Proposes that memory retrieval depends on the hippocampus during consolidation, but once consolidation is complete, retrieval no longer depends on the hippocampus. • Retrieval depends on hippocampus during consolidation • Information gradually shifts from hippocampus to cortex • Reactivation contributes to this shift - Hippocampus replays neural activity associated with memory - This occurs during sleep, relaxation, and conscious recall • After consolidation, hippocampus is no longer needed Complementary learning systems (O'Reilly & Rudy, 2001) • Hippocampus - Learns rapidly (single trial learning) - Creates distinct memories for each event/instance - More important for episodic memories • Cortex - Learns slowly - Extracts generalities across events/instances - More important for semantic memories We need both!
maintenance rehearsal
Rehearsal that involves repetition without any consideration of meaning or making connections to other information.
elaborative rehearsal
Rehearsal that involves thinking about the meaning of an item to be remembered or making connections between that item and prior knowledge.
reverse testing effect
Taking a recall test right after witnessing an event increases a participant's sensitivity to subsequently presented misinformation
exemplar approach to categorization and exemplars
The approach to categorization in which members of a category are judged against exemplars, examples of members of the category that the person has encountered in the past. may be better for smaller categories. • Exemplars - Actual examples of a category, i.e. category members • Concept is represented by multiple examples (rather than a single prototype) • Examples are actual category members (not abstract averages) • To categorize, compare the new item to stored exemplars (instead of a constructed prototype) Exemplar approach p pp is better able to handle exceptional cases. Exemplar approach p pp is better able to handle highly variable categories.
semantic network approach
The approach to understanding how concepts are organized in the mind that proposes that concepts are arranged in networks.
levels of processing (LOP) levels-of-processing theory
The idea that memory depends on how information is encoded, with better memory being achieved when processing is deep than when processing is shallow. Deep processing involves attention to meaning and is associated with elaborative rehearsal. Shallow processing involves repetition with little attention to meaning and is associated with maintenance rehearsal.
self-image hypothesis
The idea that memory is enhanced for events that occur as a person's self-image or life identity is being formed. This is one of the explanations for the reminiscence effect.
memory trace replacement hypothesis
The idea that misleading postevent information impairs or replaces memories that were formed during the original experiencing of an event.
reminiscence bump
The empirical finding that ppl over 40 have enhanced memory for events from their adolescents and early adulthood, compared to other ppl.
cultural life script and the hypothesis
The hypothesis is that events in a person's life story become easier to recall when they fit the cultural life script for their culture. Life scripts are events that commonly occur in a person's culture.
Expected utility theory
The idea that people are basically rational, so if they have all the relevant information, they will make a decision that results in the maximum expected utility. - Traditional view from economics - People are rational - If they have all relevant information, they will make decisions that maximize expected utility - Utility • Usefulness or desirability of an outcome • Monetary payoff Expected Value (EV) • The average outcome if a scenario was repeated many times. • Calculated using the probabilities and magnitudes of the possible outcomes • E.g., consider a gamble: - 75% chance of winning $200, - 25% chance of winning $0. - EV = (.75 * $200) + (.25 * $0) = $150 Simplest version claims: People will choose the option with the greatest expected value. Option A. You win $125. EV = 1.0 * $125 = $125 Option B. 25% chance you win $400, 75% chance you win $0. EV = (.25 * $400) + (.75 * $0) = $100 Therefore, most people should choose Option A. Advantages for expected utility approach - Clear prescription for "correct" choices - Leads people, on average, to maximize monetary gains given what they know about the world - Keeps people's decisions internally consistent Problems for expected utility approach - Difficult to apply for non‐monetary decisions - Doesn't explain actual choices by actual people!
Definitional Approach to categorization
The idea that we can decide whether something is a member of a category by determining whether the object meets the definition of the category. Definitional approach doesn't work so well for everyday categories. Defining features are too rigid.
prototype approach to categorization
The idea that we decide whether something is a member of a category by determining whether it is similar to a standard representation of the category called a prototype. Prototype approach • Family resemblance - Things in a category resemble one another in a number of ways • Prototype - An average of category members encountered in the past - An abstract representation of the "typical" member of a category • Characteristic features - Features that objects in the category typically have - The most salient features of the category - True of most instances of that category Rosch (1975) "Prototypicality" • Do category members vary in typicality? • Task: Rate each category member on how well it represents the category title 1 = very good category example high prototypicality 7 = very poor category example low prototypicality Rosch (1975) "Prototypicality" • Conclusion: Some objects are more prototypical of a category than others, i.e. they more closely resemble the prototype Rosch & Mervis (1975) "Family resemblance" • What makes an object more or less prototypical? • Task: "For each of the following objects, list as many characteristics and attributes that you feel are common to these objects." "Dog" Four legs, barks, fur, chases cats, tail... "Deer" Four legs, hooves, fur, eats apples, tail... "Whale" Swims in ocean, baleen, blow hole... Conclusions: - Strong positive relationship between prototypicality and family resemblance - When items share many features with other items in the category, the family resemblance of these items is high, and they are rated more prototypical - They share characteristic features Smith et al. (1974) "Typicality effect" • Does prototypicality affect performance? • Task: Sentence verification technique Respond "yes" if the sentence is true, "no" if it is false An apple is a fruit. A pomegranate is a fruit. • Conclusion: - Typicality effect: prototypical objects are processed preferentially - Highly prototypical objects judged more rapidly Mervis et al. (1976) "Naming" • Does prototypicality affect naming? • Task: Name as many members of a category as possible. • Result: - More prototypical members of a category are named before less prototypical members Bird: robin, cardinal, raven, sparrow, seagull, ostrich, penguin
narrative rehearsal hypothesis
The idea that we remember some life events better because we rehearse them. This idea was proposed by Neisser as an explanation for "flashbulb" memories.
constructive nature of memory
The idea that what people report as memories are constructed based on what actually happened plus additional factors, such as expectations, other knowledge, and other life experiences.
multiple trace hypothesis
The idea, associated with memory consolidation, that the hippocampus is involved with retrieval of remote memories especially episodic memories. This contrasts with the standard model of memory, which proposes that the hippocampus is involved only in the retrieval of recent memories. - Questions the assumption that the hippocampus is important only at the beginning of consolidation - Perhaps hippocampus is always important for memory of single episodes - Hippocampus has been shown to be activated during retrieval of both recent and remote memories (Gilboa et al., 2004)
long-term potentiation (LTP)
The increased firing that occurs in a neuron due to prior activity at the synapse. • Enhanced firing of neurons g after repeated stimulation • Structural changes and enhanced responding • Enhanced firing of neurons after repeated stimulation • Structural changes and enhanced responding • Either more neurotransmitter released from presynaptic neuron, or more receptors in the postsynaptic neuron Long‐term depression (LTD) • Neurons that fire apart wire apart? • When firing in pre‐synaptic neuron doesn't lead to firing in the post‐synaptic neuron, the connection is weakened further
cryptomesia
Unconscious plagiarism of the work of others. This has been associated with errors in source monitoring.
graded amnesia
When amnesia is most severe for events that occurred just prior to any injury and becomes less severe for earlier, more remote memories.
retroactive interference
When more recent learning interferes with memory for something that happened in the past.
transfer-appropriate processing
When the type of task that occurs during the encoding matches the type of task that occurs during retrieval. This type of processing can result in enhanced memory. Memory is enhanced if the encoding process is similar to the retrieval process
Effects of Damage to the Prefrontal Cortex (PFC)
harder time planning and perseveration, problem solving, understanding stories. reasoning, As reasoning problems become more complex reasoning activates more areas of the PFC.
retrograde amnesia
the inability to remember information from the past prior to an injury or traumatic event.
Organizing to‐be‐remembered information
• Bransford & Johnson (1972) • Presented participants with difficult‐to‐comprehend information - Experimental Group 1: First saw a picture that helped explain the information - Experimental Group 2: Saw the picture after reading the passage - Control Group: Did not see the picture • Group 1 outperformed the others. - Having a mental framework for comprehension aided memory encoding and retrieval
Patient H.M.
• Impaired LTM but functioning STM • Removal of bilateral medial temporal lobes and hippocampi pp p (to cure intractable epilepsy) • STM intact: digit span of 7 • Severe anterograde amnesia and temporally graded retrograde amnesia • Severe anterograde amnesia - Unable to form new LTMs after surgery • Temporally graded retrograde amnesia - Unable to recall old LTMs from just before the surgery H.M. showed intact implicit memory • Mirror drawing improves • But doesn't remember having done it before! • Amnesics = Controls
LTM and STM: Double Dissociation
• Impaired STM but functioning LTM - Patient K.F. • Functioning STM but impaired LTM - Patient H.M.
Patient K.F.
• Impaired STM but functioning LTM • Damage to left parietal lobe • Memory span for auditorally presented numbers, letters, and words: 2 items • Long‐term memory for words was normal • Short‐term memory for visually presented stimuli was better than for verbal material
Making Inferences
• Memory can be influenced by inferences that people make based on their experiences and knowledge • Memories often include facts that are implied by the to‐be‐remembered information but were not explicitly stated • Pragmatic inferences - Based on knowledge gained through experience Experimental group: John was trying to fix the birdhouse. He was pounding the nail when his father came out to watch him and help him do the work. • Control group: John was trying to fix the birdhouse. He was looking for the nail when his father came out to watch him and help him do the work. • Test for both groups: John was using a hammer to fix the birdhouse when his father came out to watch him and help him do the work.
Repetition Priming
• Presentation of one stimulus affects performance p on that stimulus when it is presented again • Tulving (1982) - Presented words and then fragments to be completed - Participants completed many more primed words than new words Warrington and Weiskrantz (1968) - Korsakoff's syndrome patients - Amnesia due to severe alcoholism - Showed fragmented pictures (Gollin pictures) - Identify object in as few frames as possible - Participants improved day to day, despite not remembering the previous day's training
Source Monitoring
• Source memory: - Process of determining origins of our memories Ex. remembering u heard about something from a certain person. • Source monitoring error: - Misidentifying source of memory - Also called "source misattributions" • Errors in Bartlett's study can be interpreted as inability to separate memories from story with memories from other experiences • Sharing a story with someone, only to discovery they were the one who told it to you... • After 24 hours, some non‐famous names were misidentified as famous • Explanation - Some non‐famous names were now familiar, and the participants misattributed the source of the familiarity - Failed to identify the source as the list that had been read the previous day
