memory Flashcards
define memory
process by which we retain and recall information about events that have happened in the past
define capacity
amount of information that can be stored
define duration
length of time information can held in the memory store
define coding
format in which the information is stored in the memory stores
different types of coding stores
iconic- visual
echoic- auditory
haptic- touch
gustatory- taste
olfactory- smell
2 ways information can be coded
acoustic - sounds
semantic- meaning and experience
define sensory register
temporarily stores information from our senses
features of sensory register
- unless we pay attention it disappears though spontaneous decay
- unlimited capacity
- very limited duration
- information is coded depends on the sense that picks it up
crowder (1993) research on coding in sensory register
provided information in different forms- verbally and visually
- found that information retained for a few milliseconds by iconic store, but 2-3 seconds by echoic
-there are different stores with different coding
sperling (1960) research on capacity of sensory register
flashed 3x4 grid of letters for 1/20th second and asked participants to recall on row depending on pitch played afterwards
- recall was 76% accurate showing sensory register is nearly unlimited
sperling (1960) research on duration of sensory register
varied time 0.3s and 1s tone was played after the grid
- 50% accurate with 0.3s
- 33% accurate with 1s
- concluded duration of sensory register is only about 1s
define short term memory
memory for immediate events which disappear if not rehearsed
features of short term memory
- limited capacity and duration
- acoustic coding
- maintenance rehearsal (verbal) allows the information to remain in STM
- can be forgotten through decay or displacement
jacobs (1987) research on capacity of STM
tested their ability to remember a string of letters or numbers, and if they recalled 50% accurately, he would increase the number of items until they reached their capacity
- average 9.3 numbers and 7.3 letters
- concluded it is easier to recall digits as there are less of them
miller (1956) research on capacity of STM
asking to remember a string of numbers/letters
- we can recall 7 plus or minus 2 items
- we can chunk to remember more
define chunking
putting things together to make it easier to remember and remember less
evaluation of Sperling (1960) for duration and capacity of sensory register
+ highly scientific
- lacks ecological validity
evaluation of Jacob’s (1987) on capacity of STM
- artificial and lacks ecological validity
baddeley (1966) research on coding
- asked participants to recall 5 or 10 words from a group of 4 different groups
- acoustically or semantically, similar or dissimilar
- recalled straight after for STM or 20 mins later for LTM
- concluded acoustically similar was hardest to recall for STM so it has acoustic coding
- concluded semantically similar was hardest to recall for LTM so it has semantic coding
evaluation of baddeley (1966) research on coding
- lacks ecological validity, does not consider other coding (Brandimole et al- visual coding, Frost- visual coding) or types of LTM, no control over participants variables
peterson and peterson (1959) research on duration of STM
24 undergraduate students took part in 8 trials where they were given a consonant trigram to remember and a 3 digit number to count down in 3s from
- changed retention interval 3,6,9…18
- 90% after 3s, 20% after 9s, 10s after 19s
- concluded STM has limited duration of up to 18s when rehearsal is prevented
evaluation of peterson and peterson (1959) research on duration of STM
- lacks ecological validity, lack internal validity as it may be measuring displacement if memory as STM reached capacity
wagenaar (1986) research on the capacity of LTM
created a diary of 2400 events over 6 years and texted himself on recall of events
- concluded capacity is extremely large as he recalled majority of events
define case study
very detailed investigation of an individual or small group of people
evaluation of wagenaar (1986) on capacity of LTM
- might not the tell the truth
- demand characteristics
- less objective to yourself
bahrick et al (1975) research on duration of LTM
opportunity of 392 ex american high schoolers between 17-74 years and were asked to name old classmates from yearbook either by free recall (name as many names) or photo recognition
- photo- after 15 years 90%, after 48 years 70%
- free recall- after 15 years 60%, after 48 years 70%
- concluded LTM has unlimited duration
evaluation of bahrick et al (1975) on duration of LTM
+ has high ecological validity
- confounding variables, practice effects
what is the multi store model
made by atkinson and shiffrin (1968) which explains memory passing through sensory register, to STM and then LTM
define long term memory
memory of past events
features of LTM
- unlimited capacity and duration
- semantic coding
- elaborative rehearsal converts it into LTM
- can be forgotten through interference from similar memories or retrieval failure
evaluation of MSM strengths
- different duration, capacity and coding for all stores
- brain scanning supports that prefrontal cortex is active during STM and hippocampus during LTM
- HM has hippocampus removed but he can still create STM but couldn’t make new LTM
-process of maintenance rehearsal is correct
evaluation of MSM weaknesses
- STM relies on LTM when chunking so doesn’t always have linear sequence
- STM is not unitary as when studying KF (amnesia) they were able to recall better through iconic than acoustic store
- LTM is not unitary as there is more than one type
- memories can be transferred without rehearsal like smells
- criticised for emphasis on maintenance rehearsal as deep processing is more important and memorable
define primacy effect
words are better recalled at the beginning as it had been rehearsed and transferred to the LTM
define recency effect
last few items can be recalled better as they have displaced previous ones and is in STM
Glanzer and Cunitz (1966) research in serial position effect
words at beginning and end were recalled better due to primacy and recency effect
define explicit memories
declarative because it is easy to put into words
episodic and semantic
define implicit memories
non declarative as it is not easy to put into words
procedural
define episodic memory
information about events you have actually experienced
features of episodic memory
- time stamped
- certain emotions can affect strength of the memory like trauma
- have to make conscious effort to recall