memory Flashcards
coding
the format in which information is stored in the various memory stores
capacity
amount of information that can be held in a memory store
duration
length of time information can be held in a memory store
short term memory
- limited capacity
- coding - mainly acoustic
- between 5-9 terms
- duration betwen 18-30 secs
long term memory
- permanent
- coding - mainly semantic
- unlimited capacity
- can store memories for a lifetime
peterson and peterson (1959)
- A lab experiment where 24 participants shown very briefly meaningless trigrams
- 3 sec - 80% of trigrams recalled
6 sec - 50%
18 sec - less than 10% - Study shows when verbal rehearsal is prevented information in the STM lasts 18 seconds
eval of peterson
+ lab with high levels of control - possible to repeat the study improving its reliability
- lacks ecological validity, artificial task
bahrick (1975)
- 392 participants aged 17-74 using high school yearbooks
recall was tested:
1. photo-recognition test from 50photos
2. free recall test where ppts recalled all names from class - recall started from 90% and declined to 30% after 48 years
- shows LTM has a very long duration
eval of bahrick
+ ecological validity
- field experiment - difficult to control for confounding variables
miller
established digit span was between 5-9, with the avergae being 7
baddeley (1966)
encoding in stm is acoustic
encoding in ltm is semantic
episodic
LTMs of events/experiences in our lives, time-stamped, consciously recalled
semantic
knowledge of the world, more complex than ‘facts’
procedural
skilled behaviour e.g riding a bike
working memory model
baddeley and hitch (1974) - theoretical cognitive model of information processing in stm
central executive
controls working memory by allocating resources and making decisions about what information should be processed
phonological loop
processes verbal material
phonological store
temporary storage of verbal material
articulatory process
maintenance rehearsal
visuo-spatial sketchpad
processes visual and spatial information by storing (visual cache) and manipulating information (inner scribe)
episodic buffer
integrates information processed in the other subsystems and links with LTM
interference
forgetting because one memory blocks another, causing one or both memories to be distorted or forgotten
retroactive interference
new information disrupting retrieval of old
proactive interference
old information disrupting retrieval of new
similarity - mcgeogh and mcdonald
learning similar lists of words produced the most interference and the most forgetting (mcgeoch and mcdonald)
real life forgetting
rugby players recall of the last team they played depended on how many matches they had played before (baddeley and hitch)
context dependent retrieval
godden and baddeley
- scuba diver study
state dependent retrieval
goodwin
- alcohol study e.g hiding money
retrieval failure
memory being available but not accessible
cues
a trigger that enables access to memories
encoding specificity principle
tulving - recall is better when the cues that were present when we learnt something are present when we recall it
meaningful cues
cue linked to material-to-be-accessed in a meaningful way. other cues also encoded at the time of learning (context or state)
loftus and palmer
car crash study - leading questions e.g contacted/smashed affected speed estimates given
bartlett
memories arent accurate, ‘snapshots’ - influenced by attitudes by attitudes, stereotypes, bias
post event discussion
discussing events after alters the accuracy - could be memory conformity
gabbert
71% compared to 0% memory conformity with post event discussion
anxiety increasing recall
state of arousal could improve general awareness. emotional aspect could increase memory encoding
- yuille and cutshall real life study 4 months after shooting - those who reported higher levels of stress were more accurate (88%)
anxiety decreasing recall
high levels of anxiety produces poor recall of perpetrator
- johnson and scott: high anxiety - 49%, low anxiety - 33%
- tunnel theory - witness’s attention narrows to focus on a weapon, because its a source of anxiety.
yerkes-dodson law of arousal
conflicting results could be explained by accuracy increasing as anxiety raises due to attention, to a point at which anxiety becomes too high and more stress results in lower accuracy
fisherman and geiselman’s cognitive interviews
- context reinstatement
- report everything
- recall from a changed perspective
- recall in reverse order
- CI is time consuming
kebell and wagstaff - found that most police forces have provided only a few hours training
+ some elements might be more valuable than others
cognitive interview
milne and bull - using a combination of report everything and context reinstatement produced better recall than any other conditions
+ support for the effectiveness of CI
meta analysis by kohnken - enhanced CI consistently provided more correct information than the standard interview with the police
