long term memory: structure EXAM 2

STM, WM, LTM (duration, capacity, and code)

STM: short term memory (working memory), active contents

• short duration, small capacity, phonetic code

LTM: no longer active; retrieved

• long duration, large capacity, semantic code

serial position effect

individuals tend to recall the first (primacy effect; more likely to get to LTM) and last (recency effect) items in a sequence the best, while forgetting the middle items

case of H.M. - henry molaison

epilepsy; bilateral removal of hippocampus

intact STM

intact LTM from operation

unable to commit NEW info to LTM

case of Clive Wearing

viral encephalitis, swelling in brain damaged hippocampus

intact STM

intact LTM from long ago

inability to commit new info to LTM

case of Jimmie G.

korsakoff’s syndrome, damage to hippocampus

intact STM

intact LTM from long ago

inability to commit new info to LTM

case of K.F.

parietal lobe damage

STM capacity of just 2

reduced recency effect

functioning LTM

population dissociation

no difference between populations on one measure, but a difference between populations on another

other implications: one damaged system is responsible for the deficient form of memory

second, intact system is responsible for normal functioning form of memory

explicit memory

declarative, conscious, intentional

episodic memory

personal events

semantic memory

facts, knowledge

implicit memory

memory can occur without explicit awareness or deliberate retrieval

priming

exposure to a stimulus influences response to a later stimulus without conscious awareness

procedural memory

enables the automatic performance of tasks and motor skills without conscious thought

conditioning memory

unconsciously learning associations between stimuli or actions without deliberate effort

retrograde amnesia

cannot remember events PRIOR to brain damage

memories from distant past usually better preserved

anterograde amnesia

cannot later remember events that occur AFTER brain damage

vague recollections, spontaneous productions, skill learning

Warrington and Weiskrantz (1970) - how did they demonstrate a population dissociation exploring memory capabilities of amnesiac patients when compared to health controls? what do their findings reveal about explicit memory versus implicit memory?

demonstrated population dissociation by comparing amnesiac patients with healthy control participants on different types of memory groups

explicit and implicit memory are separate systems; memory is not single, unified process; different brain systems support different types of memory

what is a direct test of memory?

directly refer to a past event; subjects are instructed to use memory; aware that using memory (explicit memory)

what is an indirect test of memory?

do not refer to past events; no mention of memory; simple ask to perform current task; memory may be without awareness (implicit memory)

how did Jacoby and Dallas (1981) demonstrate an experimental dissociation between explicit and implicit memory?

demonstrated an experimental dissociation between explicit and implicit memory by manipulating depth of processing at encoding and then measuring its effects on two different types of memory tasks

summarize the converging evidence that shows explicit and implicit memory involve different memory systems

population dissociations- compare different groups; damage to certain brain areas selectively disrupts explicit memory, suggesting separate systems

experimental dissociations- shows that the two types of memory rely on different underlying processes

developmental dissociations- systems have different developmental timelines, supporting independence

drug-induced dissociations- the two substances are differentially affected by neurochemical changes