Working Memory cont. Demos and reviews PSY 368 Human Memory Working Memory cont. Demos and reviews

Baddeley’s Model Articulatory Visual scribe Control Episodic buffer = back-up storage - allows for recall when other systems are engaged with other tasks

Phonological Loop Two parts: Phonological Store (PS) and Articulatory Control Process (ACP) PS - stores auditory info for 1-2 s and then it starts to decay ACP - recodes visual info into auditory code for storage and controls rehearsal 4 Main Effects in Serial Recall Task to account for Phonological similarity effect Articulatory suppression effect Irrelevant speech effect Word length effect This model of the phonological loop is consistent with several memory effects:

Phonological Loop Demos Listen to list, recall words in order Listen to list, recall words in order, while I read the words say ‘the’ aloud Listen to list, recall words in order, while I read the words say ‘the’ aloud Read list, recall words in order, while I read the words say ‘the’ aloud Rhinoceros Zinc Gorilla Tuberculosis Measles Calcium Uranium Carbon Hippopotamus Mumps Planet Musician Land Property Trumpet House Star Comet Orchestra Moon Bronze Book Magazine Bike Copper Dress Copier Soda Shoe Rock Block Brick Stick Blue Chew Trick Prick Clue Click Blimp Gold Code Bold Hold Told Cold Mode Slowed Hope Goad Word list: rhinoceros (4), zinc (1), gorilla (3), tuberculosis (5), measles (2), calcium (3), uranium (4), carbon (2), hippopotamus (5), mumps (1) Count backward from 756

Phonological Loop Phonological Similarity Effect e.g., Baddeley (1966) List 1 (Easy to remember/dissimilar phonology and semantics): PIT, DAY, COW, PEN, HOT List 2 (Only slightly harder than List #1/similar semantics) : HUGE, WIDE, BIG, LONG, TALL List 3 (Much harder than List #1/similar phonology) : CAT, MAP, MAN, CAP, MAD Memory worse for items that sound alike than those that look alike or have similar meanings Visual items are recoded to auditory for storage and rehearsal by ACP Works for both auditory presentation and visual presentation of the letters. We talked about this last time in terms of studies that compared letters that looked or sounded alike (Conrad) and words that had similar meanings or sounded alike (Baddeley). What happens if you prevent the recoding of visual information into auditory information?

Phonological Loop Articulatory Suppression Effect Engaging in an auditory task after study removes phonological similarity effect for visual items Procedure: Say “the” aloud over and over No re-coding of visual info by ACP Phonological info gets in directly, doesn’t need re-coding Auditory presentation: PGTCD (similar sounding) harder to recall than RHXKW (different sounding) Auditory task = repeating “the” Also lowers auditory recall With suppression Visual presentation: PGTCD (similar sounding) recalled equally as RHXKW (different sounding) No re-coding, so no chance for similar sounds to interfere

“nine six seven eight three two” Phonological Loop Irrelevant Speech Effect Background speech presented during study decreases memory for visual items Salame & Baddeley (1982) 9 6 7 8 3 2 ‘one’ ‘four’ ‘five’ Semantically similar ‘tun’ ‘sore’ ‘fate’ Phonologically similar ‘tennis’ ‘double’ Phonologically different Quiet control “nine six seven eight three two” Presumably, there is still something stored in the visuospatial sketchpad, but this system not as efficient as the phonological loop

Phonological Loop Irrelevant Speech Effect Conclusions: Background speech presented during study decreases memory for visual items Salame & Baddeley (1982) Amount of disruption is determined by phonological similarity In other experiments showed no word-length effect for irrelevant speech If rehearsal is prevented, irrelevant speech effect disappeared Presumably, there is still something stored in the visuospatial sketchpad, but this system not as efficient as the phonological loop Conclusions: Irrelevant speech interferes with recoding of visual info to auditory

Phonological Loop Word-length Effect Results Baddeley, Thomson, and Buchanan (1975) Results Recall decreases as the length of time it takes to say a word increases. Rehearsal takes longer for longer words - can’t rehearse as many times Word list: rhinoceros (4), zinc (1), gorilla (3), tuberculosis (5), measles (2), calcium (3), uranium (4), carbon (2), hippopotamus (5), mumps (1) Count backward from 756 Retrieval from PS also takes longer due to auditory coding of items Reading rate correlated with memory ability Digit span depends on language - how long it takes to say numbers

Baddeley’s Model Potential Problems with the model Some of the supportive results can’t be replicated (e.g., irrelevant speech effect) Model can’t explain all results: why word-length effect is larger for visual than auditory items why it differs based on serial list position Why some effects persist after extended delays (e.g., 5 mins) Model is not precise in explanation of effects Irrelevant speech effect failed to be replicated by some later studies. Other studies found that the effect is produced with a non-speech sound (tone). Some critics prefer a more quantitative model that can make more specific predictions and has more precise explanations of certain phenomena (e.g., Nairne model).

Cowan’s Activation Model WM = info that is currently highly activated from STM or LTM Focus of attention Emphasizes attention’s role in activation Activation of info when attention is oriented to it Activation will decay to cause loss of info from WM (also interference) STM Activation is proposed to increase when attention is paid to items in WM. WM

Cowan’s Activation Model Central Executive Focuses attention and other control processes Capacity of about 4 chunks Duration of 20s without reactivation STM activated items that are just outside of attention - passive store Things within attentional focus are available to consciousness STM Outside of attention = not activated enough to be within conscious attention WM

Cowan’s Activation Model Potential problems with the model Only general descriptions so specific predictions are hard to make Activation is not operationally defined very well - when is something is “activated”? What causes decay? Passage of time isn’t causal

Nairne’s Feature Model Items represented in WM as individual features (e.g., color, length, etc.) Features indicate presentation info (e.g., font, size, gender of voice, etc.) meaning info (e.g., what the item means, category, etc.) Stays the same regardless of presentation Features represented by -1 or +1 when studied (yes or no for a feature, 0 if no info for feature) Interference: Later items with same features overwrite feature info for previous items Developed to address some criticisms of Baddeley and Cowan models - quantitative to make more specific predictions - interference instead of decay, etc.

Nairne’s Feature Model Bold Lower Upper Blue SCHOOL +1 -1 +1 -1 fish +1 +1 -1 -1 • “fish” presented after “SCHOOL” - features in common can be overwritten - SCHOOL can become 0, -1, +1, 0 - interference During retrieval, item features are compared with items in memory - lost features can be updated and restored 0 = no info available for that feature

Nairne’s Feature Model Quantitative model - numerical predictions are possible - can simulate data to generate predictions for studies Simulations show that model can predict: 1) Recency effect 2) Suffix effect 3) Phonological similarity effect 4) Word length effect Simulations done in studies show that the feature model can predict these effects: Based on overwriting aspect of model - #4 due to more features to encode in longer words so more errors possible Recall that the suffix effect is a reduction of the recency effect when an auditory item follows the last item in the list.

Summary of WM Focus on processing (vs. storage) Three main modern models Baddeley model Central executive controls VS, PL, EB Cowan activation model WM = attention focus, STM = activated Nairne feature model (quatitative) Items coded as features with overwriting interference Parsimony is one of the canons of the scientific method.

Exam 1 review Chapters 1-4 Baddeley’s model Phonological loop Ebbinhaus and forgetting curve Episodic buffer Seven Sins of Memory Visuo-spatial buffer Review of research methods Cowan’s model Modal systems theory(ies) of memory Nairne’s model Sensory memory Duration, capacity, encoding, retrieval from the different memory systems Iconic and echoic Partial report task Various Effects (suffix, modality, etc.) Short term memory Identify the “classic experiments & researchers” Chunking Serial and free recall Recency and primacy Working memory Parsimony is one of the canons of the scientific method.