Social Memory. The Function of Perception. Perception, Categorization, and Memory. Relations Between Perception and Memory

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The Function of Perception Social Memory Fall 215 Forming Mental Representations of Objects and Events Experienced in the... Present Environment so that Behavior is Governed by the Meaning of the Current Stimulus Perceptual Activity Ends with the Identification and Categorization of the Distal Stimulus 1 2 Perception, Categorization, and Memory If every act of perception involves an act of categorization. (as Bruner said it did) Memory provides the conceptual knowledge that permits categorization to occur. Relations Between Perception and Memory Memory as Background of Perception Knowledge, Expectations, Beliefs Cognitive Basis for Perception Memory Trace as a Byproduct of Perceptual Activity Record of Perceptual Activity Description of Percept 3 4 Decomposition of Human Form into Cylinders Marr & Nishihara (1978) More Cylinder-Figures Marr & Nishihara (1978) 5 6 1

Decomposition into Geons Biederman (1985) Some Phenomena of Face Recognition Classification of Errors in Face Recognition Familiarity Identification 7 Prosopagnosia Cannot Recognize Familiar Faces Can Determine Gender, Emotional Expression Can Read Lips Evidence from Reaction-Time Studies Familiarity < Occupation < Name 8 Cannot State Name Before Occupation (?) Model of Face Recognition Bruce & Young (1986, 212); Young & Bruce (1991, 211) Parallels Between Face, Object, and Word Recognition Bruce & Young (1986) Face Recognition Unit 1/Person Activated by Recognition Person Identity Node 1/Person Face Belongs to Person Semantic Information Units Occupation Personality Name Recognition Unit Verbal Label 9 1 Interactive Activation Model of Face Recognition Burton et al. (199) Taxonomy of Memory Procedural Declarative Motor Cognitive Episodic Semantic 11 12 2

Two Forms of Knowledge Winograd (1975); Anderson (1976) Declarative Knowledge Factual Statements Propositional Format Procedural Knowledge Directions for Action Production Format Declarative Knowledge Factual Statements About World, Past Sentence Format Propositions Subject - Verb Object Types of Representations Meaning-Based Verbal Description Perception-Based Mental Image A bicycle is a twowheeled vehicle with seat and handles, propelled by pedaling. A bicycle looks like this: Strand Theatre, Shelbyville IN 13 14 Procedural Knowledge Directions for Goal-Directed Action If-Then Format (Productions) Goal - Condition Action Production System Motor Actions Take Form of Overt Behavior Alter Objective, Publicly Observable World Mental X + 6 = 38 Actions Take Form of Mental Transformation Alter Internal, Private Mental Representations Scouthelper 15 Types of Declarative Knowledge Tulving (1972, 1983) Episodic Autobiographical Memory Factual Knowledge About Personal Experiences Spatio-Temporal Context Self-Reference Semantic Mental Dictionary or Encyclopedia Abstract, Conceptual Knowledge About the World 16 Episodic Memory Autobiographical/Personal Specific Experiences Narratives Elements Description of event Episodic context Time, Place Causal Relations Self-Reference Agent or Patient, Stimulus or Experiencer Internal Mental State 17 Semantic Memory Abstract, Context Free Mental Lexicon Generic Memory? Object Knowledge Linguistic Knowledge Categorical Knowledge Subsets-Supersets Similarity Category-Attribute 18 3

Declarative Social Memory Factual Knowledge Has Truth Value Propositional Representation Subject-Relation-Object The subject verbed the object Propositional Network Examples John smiled at Lucy John is a neurotic extravert Neurotics are anxious and excitable, while Extraverts are talkative and sociable 19 Structure of Declarative Memory Nodes Represent Concepts Associative Links Represent Relations Among Concepts Perception Activates Corresponding Nodes Activation Spreads Across Associative Links Spreading Activation Creates Priming Processing of One Event Facilitates or Impairs Processing of Another 2 Propositional Representation After Anderson (1976) An Associative Network The Hippie Touched The Debutante Vehicle Truck Porsche Contact Car VW Bus Kissed The hippie touched the debutante Stringy Blonde Long The Hippie Touched the Debutante 21 Hair Short 22 Relations Between Episodic and Semantic Memory Memory in Social Cognition Semantic Knowledge Begins in Episodes Learning Experiences Accumulation Blurs Episodic Features Episodic Memory Formed Against Background of Semantic Knowledge Cognitive Basis for Perception 23 Procedural Motor Eye Contact Handgrip Display Rules Interpersonal Distance Cognitive Impression Formation Self-Regulation Declarative Semantic Implicit Personality Theory Episodic Autobiographical Memory Person Memory 24 4

Person Memory Knowledge Concerning Another Person Mix of Declarative Memories Episodic Memories of Past Encounters Knowledge of Behavioral Episodes Semantic Generic Knowledge About Person Traits, Attitudes, Other Characteristics Memory and Person Memory Person Memory Can Be Studied with Techniques Used in Nonsocial Memory Social Context is Important Impression Formation Improves Person Memory What Do Person Memories Look Like? 25 26 Kind Associative Structure of Person Memory Thoughtless Individuation and Reference in Person Memory Anderson & Hastie (1974) First You Learn: rescued the kitten. adopted the child. The lawyer caused the accident. The lawyer cursed the salesgirl. 27 28 Individuation and Reference in Person Memory Anderson & Hastie (1974) First You Learn: rescued the kitten. adopted the child. The lawyer caused the accident. The lawyer cursed the salesgirl. Then You Learn: is the lawyer. 29 Individuation and Reference in Person Memory Anderson & Hastie (1974) First You Learn: rescued the kitten. adopted the child. The lawyer caused the accident. The lawyer cursed the salesgirl. Then You Learn: is the lawyer. Now You re Asked: Did cause the accident? 3 5

Retrieval from Episodic Memory Anderson (1974) Learn Facts about People, Locations The doctor is in the bank (1-1) The fireman is in the park (1-2) The lawyer is in the church (2-1) The lawyer is in the park (2-2) Memorize to criterion of perfect recall Recognition Studied targets The doctor is in the bank Unstudied lures The doctor is in the park 31 Doctor Fireman Lawyer People and Locations Anderson (1974) is in Bank Park Church 32 The Fan Effect Anderson (1974) Separate Representations Response Latency (secs) 1.6 1.2.8.4 True False Targets Locations Targets Locations Facts 1 2 3 Lawyer Item Type 33 34 Separate Representations Rescued the kitten Adopted the child Is the lawyer The Lawyer Is Caused the accident Cursed the salesgirl Can t Answer the Question Knowledge Not Represented in Memory But We Can Answer the Question 35 Single Representation Lawyer 36 6

Single Representation Linked Representations is the lawyer rescued the kitten adopted the child caused the accident cursed the salesgirl Answer Question by Memory Retrieval Knowledge Represented Directly 37 Lawyer 38 Linked Representations rescued the kitten adopted the child is the lawyer caused the accident cursed the salesgirl Answer Question by Inference From Knowledge that Bartlett is the Lawyer 39 Experimental Procedure Study Facts About About the Lawyer Learn Identity Before Learning Facts After Learning Facts Sentence Verification No Inferences rescued the kitten Inferences 4 cursed the salesgirl Response Latencies in Sentence Verification Anderson & Hastie (1974) How Persons Are Represented in Memory Response Latency (secs) 4.5 4 3.5 3 2.5 2 1.5 1.5 Before Learn Identity After * Inference No Inference 41 Node Representing a Person The Lawyer Nodes Representing Facts about Person Behaviors, Experiences Traits, Attitudes Associative Links Connect Person Nodes to Fact Nodes 42 7

Individuation and Reference If Reference Known at the Outset Reference Treated as Another Fact Is the Lawyer Individuation and Reference If Reference Learned Later Reference Links Representations Knowledge of B not Transferred to A Get from A to B via Associative Link Lawyer 43 44 Kind Associative Structure of Person Memory Thoughtless 45 Schematic Effects on Person Memory Information in Person Memory Semantic General Characteristics Episodic Specific Behaviors, Experiences What is the Relation Between Semantic and Episodic Person Memory? How Does Semantic Knowledge Affect Episodic Knowledge How are Relations Represented? 46 Memory and Schema-Congruence Bartlett (1932) Memory Favors Schema-Congruence Conflicting Results Congruence > Controls Congruence = Controls Congruence < Controls Result Depends on Control Condition 47 Schematic Effects on Person Memory Hastie & Kumar (1979) Present Trait Ensemble Traits Descriptive of Target Person Induce Schema for Person Prior Beliefs and Expectations Study Specific Behaviors Vary Relationship to Schema Schema-Congruent p(behavior Schema) > p(behavior No Schema) Schema-Incongruent p(behavior Schema) < p(behavior No Schema) Schema-Irrelevant p(behavior Schema) = p(behavior No Schema) 48 8

Sample Materials Judy is: intelligent, clever, bright, smart, quick, wise, knowledgeable, decisive Judy won the chess tournament. attended the symphony concert. made the same mistake three times. was confused by the television show. ordered a cheeseburger for lunch. took the elevator to the third floor. 49 Proportion Recalled.6.5.4.3.2.1 Schematic Effects on Memory Hastie & Kumar (1979), Exp. 1 Incongruent Irrelevant Congruent Item Type 5 Schematic Effects on Memory Hastie & Kumar (1979), Exp. 2 The Schematic Processing Principle Proportion Recalled.9.8.7.6.5.4.3.2.1,4,12 1,4,11 3,4,9 6,4,6 Incongruent Irrelevant Congruent The Memorability of an Event is a Function of its Relationship to Pre-Existing Schemata. Incongruent/Irrelevant/Congruent Mix 51 52 Two Processes in the Schematic Processing Effect Hastie & Kumar (1979); Hastie (198, 1981, 1984) Schema-Congruent Schema Provides Internally Generated Cues Facilitates Retrieval Schema-Incongruent Surprise Instigates Explanatory Activity Facilitates Encoding Schema-Irrelevant Get Neither Advantage 53 Explanation in Terms of Network Model of Memory Srull (1981) Behavioral Items Linked to Person Node Interitem Associations Among Incongruent Items Between Incongruent and Congruent Items Retrieval by Tracing Associative Links Favor Incongruent Items Most Associative Links Ignores Irrelevant Items No Associative Links 54 9

Srull s Model of Person Memory Srull (1981) Effects of Schema-Incongruent Behaviors on Memory Srull et al. (1985) Induce Schema Memorize Trait Ensemble Study Behaviors 12 Schema-Congruent 12 Schema-Neutral, 6, or 12 Schema-Incongruent Test Recall for Behaviors 55 56 Recall and Schema-Congruence Srull et al. (1985) Priming Effects on Person Memory Srull et al. (1985) Proportion Recalled.7.6.5.4.3.2.1 /12/12 6/12/12 12/12/12 Incongruent Neutral Congruent Test Recognition for Behaviors Response Latency Priming Mediated by Associative Links Between Incongruent Items Between Congruent, Incongruent Items Incongruent/Neutral/Congruent/ 57 58 Priming in Sentence Verification Srull et al. (1985) How Are Traits Represented in Person Memory? Response Latency (secs) 1 9 8 7 6 5 4 3 2 1 Congruent Incongruent Irrelevant Prime Type Target Item Congruent Incongruent Irrelevant Nodes Representing Person Behaviors Traits Relation Between Traits and Behaviors Traits, Behaviors Linked Independently Behaviors Organized by Traits 59 6 1

Traits and Behaviors Represented Independently Behaviors Clustered by Traits Kind Thoughtless Kind Thoughtless 61 62 Organization of Person Memory Klein & Loftus (199) Recall and Clustering Klein & Loftus (199) 2 Behavior Descriptions 4 per trait Athletic, Intelligent, Honest, Religious, Sociable 3 Conditions Impression Formation Memorization Category Sorting Prop Maximum 1.8.6.4.2 Impression Memorization Classification Condition Recall Clustering 63 64 Beyond Clustering: Priming Behaviors Clustered by Traits Nodes Representing Person Traits Behaviors If Behaviors Clustered Under Trait nodes Traits Should Prime Behaviors If Traits, Behaviors Linked Independently No Priming Effects 65 Kind Thoughtless 66 11

Priming Effects in Person Memory Klein, Loftus, Trafton, & Fuhrman (1992) Target Person: Mother Rate Descriptiveness of Each Trait Present Trait Term Define Describes Mother Remember Event Involving Mother Compare Performance Trial N vs. Trial N-1 Does Remembering a Trait Prime Remembering a Behavior? 67 Response Latency (secs) Traits Highly Descriptive of Mother Klein, Loftus, Trafton, & Fuhrman (1992) 9 8 7 6 5 4 3 2 1 Describe Target Task Remember Priming Task Define Remember Describe 68 Traits Less Descriptive of Mother Klein, Loftus, Trafton, & Fuhrman (1992) Implications for the Organization of Person Memory Response Latency (secs) 14 12 1 8 6 4 2 * Describe Remember Target Task Priming Task Define Remember Describe Retrieval of Highly Descriptive Traits Does Not Prime Retrieval of Trait-Related Behaviors Highly Descriptive Traits are Represented Independently of Trait-Related Behaviors Retrieval of Less-Descriptive Traits Does Prime Retrieval of Trait-Related Behaviors Trait Judgments are Based on Retrieval of Exemplary Behaviors 69 7 Evidence from Amnesia Tulving (1993); Klein & Loftus (1996) Forms of Amnesia Amnesic Patients Anterograde (Postmorbid Memories) Retrograde (Premorbid Memories) Cannot Remember Episodes No Episodic Self-Knowledge But Can Describe Personality Spared Semantic Self-Knowledge Can Even Appreciate Personality Change Source Amnesia? 71 Memory Retrograde Amnesia (Premorbid) Time Injury Anterograde Amnesia (Postmorbid) 72 12

The Case of K.C. Tulving (1993) Motorcycle Accident at Age 3 Complete Amnesia Anterograde Retrograde Personality Change Premorbid, Extraverted Postmorbid, Introverted Ratings of K.C. s Postmorbid Personality K.C. s vs. Mother s Ratings of K.C. Q =.77 K.C. s vs. Mother s Ratings of Mother Q =.8 73 74 K.C. s Personality: Premorbid vs. Postmorbid The Case of W.J. Klein, Loftus, & Kihlstrom (1996) 2-Alternative Forced Choice Matched Items for Social Desirability Reliability of K.C. s Post Ratings 76% Agreement Mother s ratings of K.C. Pre vs. Post 5% Agreement (Chance) K.C. Post vs. Mother Post 73% Agreement K.C. Post vs. Mother Pre 53% Agreement (Chance) 75 18 y/o College Undergraduate 2nd-Quarter Freshman Concussive Blow to the Head No Neurological Abnormalities Anterograde Amnesia 45 Min After Injury Retrograde Amnesia Covering Previous 6-7 Months Cleared in 11 Days 76 Memory Testing in W.J. Klein et al. (1996) Autobiographical Memory During Amnesia Klein et al. (1996) Digit Span Free Recall Semantic Memory Episodic Memory Galton Cued-Recall Technique Unconstrained Constrained Personality Testing % of Memories 8 7 6 5 4 3 2 1 <12 13-6 61-12 >12 Age of Memory (Months) W.J. Control 77 78 13

% of Memories 9 8 7 6 5 4 3 2 1 Autobiographical Memory Post-Amnesia Klein et al. (1996) <12 13-6 61-12 >12 W.J. Control W.J. s Personality in College Klein et al. (1996) Agreement with Boyfriend, College r =.65* a Controls, r =.65* a Knows What She s Like Now College vs. High-School r =.53* b Some Relation to High-School Personality Test-Retest Reliability, College r =.74 * c Controls, r =.78* c Age of Memory (Months) College Self Not Accounted For by High-School Self 79 8 Trait and Behavioral Self-Knowledge in Amnesia Amnesics Retain Knowledge of Personality Forget Knowledge of Events Trait, Behavioral Information Represented Independently Confirms Results of Priming Studies Structure of Person Memory Persons Represented as Nodes Traits, Behaviors Represented as Nodes Fan Out from Person Node Trait and Behavioral Knowledge Represented Separately Behaviors Do Not Fan Out from the Traits They Exemplify 81 82 Kind Traits and Behaviors are Represented Independently Thoughtless Neural Representation of Memory Distributed (Lashley; Hebb) Reverberating Pattern of Neural Activity Distributed Widely Over Cerebral Cortex Localist (Penfield) Activity of Single Neurons Or Small Clusters of Neurons Centered on Specific Cortical Location A Grandmother Neuron (Lettvin, 1967) 83 84 14

Invariant Visual Representation by Single Neurons Quian Quiroga, Reddy, Kreiman, Koch, & Fried (25) 8 Patients with Intractable Epilepsy Electrodes Implanted to Localize Seizures Medial Temporal Lobe Hippocampus, Amygdala Entorhinal Cortex, Parahippocampal Cortex 8 Active Microwires per Electrode Responses to Visual Stimulation Individuals, Objects, Animals, Landmarks Selection Based on Interviews with Patients Activity Spikes Within 1 Second 85 5 SD Above Baseline The Jennifer Aniston Neuron? Quian Quiroga et al. (25) Single Unit in Left Posterior Hippocampus 86 The Halle Berry Neuron? Quian Quiroga et al. (25) Single Unit in right Anterior Hippocampus 87 Summary of Findings Quian Quiroga et al. (25) Tested 993 Units 343 Single Units, 65 Multi-Units Response to 1+ Pictures in 132 (14%) Then Test 3-8 Variants 51 of 132 Showed Invariant Representation People, Landmarks, Animals, Food Items Representations are Abstract Different Views of Subject Photographs and Line Drawings Pictures and Names 88 Maybe there is a Grandmother Neuron After all! Sparse Neural Representation Small Number of Units Active At Any One Time Psychophysical Linking Principle (Barlow, 1972) Whenever two stimuli can be distinguished reliably... the physiological messages they cause in some single neuron would enable them to be distinguished with equal or greater reliability Knowledge Distributed Widely in Cortex But Comes Together in Single Units Hippocampus as Index Relates Memories to Each Other 89 15