Memory  All learning requires memory  Three stages of memory phenomena Acquisition Retention Retrieval

Taxonomy of Human Memory ProceduralDeclarative Working and Reference Memory Episodic and Semantic Memory Motor Skills Classical Conditioning Operant Conditioning automatic, incremental, unconscious effortful, conscious

Reference versus Working Memory Reference memory – long term retention of events, relationships, and procedures – associations, rules, skills. Working memory - short term retention, typically relevant only to the current trial, includes information retrieved

Working Memory in Animals Hunter (1913) food

Working Memory or Body Orientation? food

Delayed Matching to Sample (DMTS) Sample Comparison

Delayed Matching to Sample (DMTS) PECK FOOD PECK NO FOOD

Symbolic Matching to Sample

PECK FOOD PECK NO FOOD NO FOOD

What is Learned in DMTS? a)General Matching Rule Pigeon = No! (with few samples) Cumming & Berryman (1965) - Trained on Red, Green, Blue - Failed to transfer to Yellow b) Specific “If-Then Rules” Symbolic Matching-To-Sample - Learned as rapidly as Standard DMTS

Memory Coding a) Retrospective = Backward Looking b) Prospective = Forward Looking

Retrospective Code: IF, Remember Prospective Code: IF, Remember

Roitblat, 1980 Confusion Errors? 1. between samples 2. between comparisons Confusions: Comparisons > Samples Therefore: Prospective Coding

Serial List Learning Present list of items to subject one at a time A  B  C  D  E  F Recall in any order

Ask subject to recall or recognize a single item A B C D E F Accuracy Primacy effect Recency effect Serial List Learning

Humans: Testing after a delay produces a primacy effect A B C D E F Accuracy Testing immediately after list produces a recency effect A B C D E F Accuracy What about in other animals?

Radial Arm Maze

How Solved?  Random Choice  Odour Trail  Patterned Responding  Memory*

12-Arm Radial Maze

Can rats switch from retrospective to prospective memory?

Cook et al. (1985)  Rats removed after making 2, 4, 6, 8, or 10 choices  Shifting from retrospective to prospective midway produces the lowest memory load (inverted U-shaped error curve)

Cook et al. (1985) Remember Places Visited Remember Places Not Visited

Memory Coding a) Active = rehearse relevant information b) Passive = gradual fading of a memory trace

Human Forgetting Curve With No Rehearsal

Pigeon Forgetting Curve Roberts, 1972

Directed Forgetting ITI Sample Comparison don’t peck Remember cue Forget cue

peck Forget cue Delay LeastMoreMost

Human Reference Memory  Duration (relatively long-term)  Capacity (relatively large)  Forgetting (details lost, gist remembered)  Requires Consolidation

Retention of Fear Conditioning

Clark’s Nutcracker  Food Storing Bird  About 5,000 Caches  20 x 20 KM Area  9-month  Buried Under Snow

Sarah Shettleworth

Results  Birds recovered previously cached seeds and made few errors  Didn’t find seeds hidden by experimenter  Didn’t return to the same site if first storing episode is followed by a second storing episode

Summary of Animal Memory Working Memory Prospective and Retrospective Active and Passive Reference memory Duration and Capacity Forgetting and Consolidation

Do Animals have Episodic Memory?  Episodic Memory Conscious Recollection Dated Personal Memory (what, when, and where)

Western Scrub-Jay (Nicola Clayton)

Clayton’s Results

Metamemory in Rats?  Knowledge of the state of one’s own memory for example, memory strength  Foote and Crystal (2007) Duration of noise sample, 2.00 to 3.62 = Left Duration of noise sample, 4.42 to 8.00 =Right Choice to continue → memory test, large reward Choice to bail-out → no test, small reward

Foote and Crystal (2007) Procedure

Foote and Crystal (2007) Results

Problems  Only 2 of 3 rats showed positive results (5 others always bailed or always decided)  Maybe they learned to bail with feedback on the “close” duration values?