Memory v2 Flashcards
Define memory.
Memory is the process of retaining information and accessing this information when needed.
What is the sensory register?
A store which contains unprocessed impressions of information retrieved through the senses
What is the STM?
Temporary store for information received through the SR
What is the LTM?
Permanent store holding limitless amount of information for long periods of time (lifetime)
Describe the coding, capacity and duration of the SR.
CODING: SR is modality specific so each sensory store codes information differently e.g. iconic, auditory
CAPACITY: unlimited
DURATION: 250 ms
Describe the coding, capacity and duration of the STM.
CODING: it’s coded acoustically - info sorted according to its sound
CAPACITY: 7+/- 2 units of information
DURATION: 18-30 seconds
Describe the coding, capacity and duration of the LTM.
CODING: coded semantically - information sorted by their meanings
CAPACITY: unlimited
DURATION: potentially lifetime
Outline a study that supports the coding of the STM.
Baddeley (1966)
- 4 lists of words (similar sounds, dissimilar sounds, similar meanings, dissimilar meanings)
- Tested pps. to recall the words
- Worse recall with A compared to B, no diff in C and D
- STM is stored by sounds so similar sounding words got muddled and were more difficult to recall
Outline & evaluate a study to support the coding of the LTM.
Baddeley (1966)
- repeated experiment after 20 minutes
- Tested the pps recall
- Recall of list C was worse than D
- A and B recall was similar
- LTM information is stored by meaning
- Similar meaning words get muddled and thus recall is worse
ADV: lab experiment, easy to replicate and test for reliability, control over extraneous var.
DIS: low ecological validity, lists were artificial, doesn’t apply to real life
Outline and evaluate a study to support the capacity of the STM.
Jacobs (1887)
- Digit span test
- Gave pps several sequences of digits or letters and asked them to repeat the sequence immediately
- Sequences got longer by one item each time
- On average 9.3 digits and 7.3 letters (7 +/- 2)
- new incoming info DISPLACES old info if capacity is exceeded
- five words = five letters so CHUNKING helps remember more
ADV: first to ack that STM capacity improves with age
DIS: Very old study, may not meet today’s scientifically rigorous standard, validity in question
Discuss a study to support the duration of STM.
Peterson & Peterson (1959)
- Nonsense trigrams (three random consonants)
- asks pps to count back from 100 in 3s (prevents maintenance rehearsal)
- After 3 secs: 90 % accuracy
- After 9 secs: 20%
- After 18 secs: 2%
- Exceeding duration, info is lost to decay
ADV: Standardised procedures, fixed timings to count back, eliminated noise and other factors that affect memory, high level of control
DIS: Findings caused by interference rather than differences in duration (confusion with initial trigrams)
Outline a study to support LTM duration.
Bahrick (1979)
- 400 pps of varying age
- Photo recognition test with 50 images (if they’re classmates, and their name)
- free recall: 60% names within 15 yrs of leaving school; 30% after 48 yrs
- Conclude that duration is a lifetime but requires retrieval cues to access this information
ADV: higher ecological validity than Peterson & Peterson - uses meaningful information that can apply to real everyday life
DIS: Difficult to control extraneous var. (pps who are in touch after school/ looking in yearbook since they left)
Define the Multi-store Model of Memory (Atkinson & Shiffrin)
A memory model which explains how information flows through the three structures: sensory register; short term memory; long term memory.
Describe steps in the MSM
- Environmental stimuli enters the SR
- If information in the SR is attended to, it’s acoustically coded into the STM
- Information is kept in STM through maintenance rehearsal
- Information can be elaboratively rehearsed (organised in meaningful way) to store in LTM
- Rehearsed info is semantically coded into LTM
- Information is retrieved first to the STM then recalled
- Sometimes we need retrieval cues to retrieve information from the LTM
Evaluate MSM
ADV 1: HM
- Patient had his hippocampus removed in a surgery to treat his epilepsy
- This means he was unable to code new LTMs but his STM was unaffected.
- THUS LTM and STM are separate stores.
ADV 2: KF
- Got into an accident and the capacity of his STM was reduced to 1 or 2 units.
- Yet his LTM was normal - supports idea of separate STM and LTM
- (*poor STM for verbal not visual suggests more than one type of STM, ALSO if STM damaged it should be difficult to retrieve from LTM)
DIS 1: Over simplified
- One type of STM and LTM
- Research suggests several types of each
DIS 2: Cannot explain multi-tasking
- Only one type of STM = not possible to multitask
Outline the working memory model
A model of memory where STM was an active store holding several pieces of information while they are being worked on while LTM is a passive store that only holds previously learned material to be used by the STM when needed
What is the central executive
- drives the working memory system
- allocates data to other components aka slave systems
- deals with cognitive tasks: reasoning, decision making, problem solving
- allocates attentional capacity to tasks