Lecture 2 – Psyco 350, A1 Winter, 2011 N. R. Brown Psyco 350 Lec #2 – Slide 1 Outline • • • • A Little History Information Processing & the Modal Model Memory Systems Aspects of Modal Model: – STM vs LTM: Serial Position Curve – Properties of STM • Capacity: Span Task • Duration/Forgetting: Brown Peterson Task • Retrieval: Sternberg Task Psyco 350 Lec #2 – Slide 2 A Very Little Bit of History Psyco 350 Lec #2 – Slide 3 Hermann Ebbinghaus (1850-1909) • Father of Memory Research • Memory stripped of meaning • Inventor of the nonsense syllable (DAX, FOZ, KIR) • Discoverer of: – Learning curve – Forgetting function Psyco 350 Lec #2 – Slide 4 Fredrick Bartlett (1850-1909) • Impact of prior knowledge and meaning on memory. • Most important ideas: – reconstruction – schemata Psyco 350 Lec #2 – Slide 5 Verbal Learning • Emerged from Behaviorism • Focus: – relationship between external variables and human memory performance – forgetting and theories of forgetting • Approach: – Rigorously conducted, list learning (often paired associate) experiments Psyco 350 Lec #2 – Slide 6 Historical Precedence Ebbinghaus Verbal Learning Behaviorism Contemporary Memory Research Bartlett Information Processing Cog Psych Psyco 350 Lec #2 – Slide 7 And Now … Cognitive Research Memory Research Psyco 350 Lec #2 – Slide 8 Information Processing • Core metaphor: human mind as serial computer • To understand/describe computer behavior, specify: – hardware – software – available data Psyco 350 Lec #2 – Slide 9 Information Processing To understand/describe human behavior, specify: • the cognitive architecture (hardware) – identify components & their general function: – characterize components in terms of: • capacity • speed • accuracy • a cognitive task analysis (software & data) Psyco 350 Lec #2 – Slide 10 Information Processing Cognitive Task Analysis (software & data): • What are the mental operations required to perform a task? • How are the operations sequenced? • What information is involved in task? • How is the information accessed? • How is it represented? • How is it altered during the processing? Psyco 350 Lec #2 – Slide 11 A Simple Computer Architecture • Input devices/registers • Active memory and processing • Inactive (but accessible) memory Psyco 350 Lec #2 – Slide 12 Modal Model of Memory • The standard model of memory • Atkinson & Shiffrin (1968) • Four components – Sensory registers – Short-term memory – Long-term memory – Control processes Psyco 350 Lec #2 – Slide 13 Modal Model of Memory Psyco 350 Lec #2 – Slide 14 Psyco 350 Lec #2 – Slide 15 Psyco 350 Lec #2 – Slide 16 Psyco 350 Lec #2 – Slide 17 Modal Model: Component Functions 1. Sensory stores: function: buffers sensory input for selection and identification 2. Short-term Memory function: temporal storage during processing 3. Long-term Memory function: store declarative & procedural knowledge declarative -- knowing that procedural -- knowing how 4. Attention function: Selection and transfer from sensory stores Maintenance of information in STM Selection and scheduling of tasks Psyco 350 Lec #2 – Slide 18 Multiple (Long-term) Memory Systems • Long-term memory involves several subcomponents • Different memory systems for different types of information Psyco 350 Lec #2 – Slide 19 Multiple Memory Systems • Memory – Declarative Memory (explicit memory) • Semantic memory –“permanent,” decontextualized knowledge • Episodic memory –“forgettable” event memories – Nondeclarative memory (implicit memory) • Procedural memory • Classical conditioning • Priming Psyco 350 Lec #2 – Slide 20 Memory as Everything – A Simple Demonstration • • • • • • • • (read &) store 1st #: (read &) store 2nd #: Retrieve-execute: retrieve top ones digit: retrieve bottom ones digit: retrieve addition fact: store ones sum: retrieve-execute: – retrieve top tens digit: – retrieve addition fact: – store new top tens digit: • • • • • • retrieve top tens digit retrieve bottom tens digit: retrieve addition fact: store tens sum Retrieve, combine sums State answer: Psyco 350 Lec #2 – Slide 21 [84] blue = WM [57] [2-digit addition strategy] red = procedural [4] memory [7] [4+7=11] green = semantic [1] memory [carry operation] [8] [8+1=9] [9] [9] [5] [9+5=14] [14_] [14; 1 141] “141” Modal Model: Evidence STM – LTM Distinction • Assumption: – dual stores – STM & LTM: • small amount of info held briefly in STM • rehearsal enables and is required for transfer from STM to LTM • Support: serial-position-curve phenomena Psyco 350 Lec #2 – Slide 22 Free Recall & the Serial Position Curve Memory Tests Recall Cued Uncued Serial Psyco 350 Lec #2 – Slide 23 Recognition FREE Free Recall Task Instructions: There are 15 words on this list. When I say to, please write down as many of these words as you can. List #1 – 15 words Psyco 350 Lec #2 – Slide 24 Free Recall Task Instructions: There are 15 words on this list. When I say to, please write down as many of these words as you can. List #2 – 15 words; 20 s delay Psyco 350 Lec #2 – Slide 25 Free Recall & the Serial Position Curve • Free recall: – uncued recall of studied items – order of output unconstrained • Manipulate a variety of: – Encoding factors (e.g. presentation rate) – Storage factors (e.g., delay) • Dependent variable: – % recalled as a function of serial position Psyco 350 Lec #2 – Slide 26 Serial Position Curve • Primacy: Good recall for 1st few items • Recency: Good recall for last few items on list Psyco 350 Lec #2 – Slide 27 Modal Account of the Serial Position Curve • Recency Effect produced by read-out from STM • Primacy & “pre-recency” reflect information retrieved from LTM • “Transfer” from STM to LTM caused by rehearsal. • Implications: – Primacy & Prerecency: w/ rehearsal – Recency: unaffected by rehearsal Psyco 350 Lec #2 – Slide 28 Rundus (1971): Rehearsal & the Serial Position Curve • Materials – 20-word list – presentation rate: 5 s/word • Task(s): – During study – overt rehearsal – During test – free recall Psyco 350 Lec #2 – Slide 29 Rundus: Rehersal Protocols Psyco 350 Lec #2 – Slide 30 Relation between Rehearsal & Recall • Analysis: – # rehearsals for each word (position) – % recall for each word (position) • Results: – “For a given amount of rehearsal, items from the initial serial positions are no better recalled than items from the middle of the list” – Rundus, 1971, p. 66 Psyco 350 Lec #2 – Slide 31 Relation between Study-time (Rehearsal) & Recall s t y d • Glanzer & Cunitz (1966) • manipulate studytime. • Assume: study time & rehearsal related • Results: – Primacy & Prerecency: w/ study time – Recency: unaffected by rehearsal Psyco 350 Lec #2 – Slide 32 Relation between Filled Delay & Recall s t y d • Glanzer & Cunitz (1966) • Manipulate retention interval. • Assume filled delay replaces contents of STM • Results: – Primacy & Prerecency: un affected by delay – Recency as delay Psyco 350 Lec #2 – Slide 33 Amnesia & Serial Position s t y d Psyco 350 Lec #2 – Slide 34 • Baddeley & Warrington (1970) • H.M. – removal temporal lobe and hippocampus • Clobbered Explicit memory. • Yet – on immediate test, recency intact Dissociation: Evidence for Dual Store • Dissociation – when “a single variable has different affects on two or more measures.” • Evidence for separate stores, processes, or representation. • Many variables have dissociative effect on the prerecency & recency portion of serial position curve. Study time Post-list distraction Ant. Amnesia List Length Word Frequency Psyco 350 Lec #2 – Slide 35 Prerecency Recency = = = =