memory Flashcards
Research on coding:
Baddeley:
- group 1/2 acoustically similar/dissimilar
- group 3/4 semantically similar/dissimilar
- STM acoustically
- LTM semantically
Research on capacity:
Digit span: Jacobs
- gives digits to recall until no longer can, mean for digits: 9.3 mean for letters: 7.3
Span + chunking: Miller
- everyday practice things come in 7’s, can recall 5 words (chunking)
Research on duration of STM:
Peterson + Peterson, 24 undergrads, 8 trials
-given a trigram and 3 digit number to count backwards from (prevent mental rehearsal)
- stop at different times (3, 6, 9, 12, 15, 18…) retention interval
- findings= 3 seconds 80%, 18, 10% correctly recalled
Research on duration of LTM:
Bahrick, 392 pp, 17-74, yearbooks obtained
1. photo recognition,
15 years= 90% accurate
48 years= 70%
2. free recall
15 years= 60%
48 years= 30%
Evaluation of research on coding:
- artificial stimuli, no meaning, difficult to generalise to everyday life, limited application
Evaluation of research on capacity:
- Lacks validity, (temporal) early research lacked control, confounding variables (pps distracted), however results confirmed in other studies
- Miller overestimated capacity, Cowan concluded capacity= 4 chunks, millers 5 items more appropriate than 7
Evaluation of research on duration:
- meaningless stimuli (STM) artificial, lacked external validity, however we do remember phone numbers so can be applied to every day life
+ high external validity (LTM) real life meaningful memories, when compared with meaningless (Shepard) recall was lower
- however confounding variables not controlled e.g how often they looked at yearbooks
What is the multi store model of memory?
prolonged rehearsal
SR > STM > LTM
< retrieval
maintenance rehearsal
Explain what the sensory register is:
- recieves stimulus from environment
- 2 main stores iconic, visual, echoic, auditory
- duration= 1/2 second
- capacity= 100 million cells
- coding= acoustically
Coding, capacity and duration of STM:
- coding= acoustically
- capacity= 7+-2
- duration= 18-30 seconds
Coding, capacity and duration of LTM:
- coding= semantically
- capacity= unlimited
- duration= lifetime
Evaluation for multi store model:
+ Supporting evidence, Baddeley supports STM and LTM being 2 distinct separate stores, different coding (Jacobs, Peterson)
- artificial materials in research (meaningless)
- there are 2 types of rehearsal (Craik, Watkins)
maintenance= described in model however only keeps in STM
elaborative= not in model, needed for long term storage (link to knowledge)
cannot be explained by MSM - STM is not a unitary store, (Shallice, Warrington) KF verbal info impaired, visual unaffected, separate components shown in WMM
What are the types of LTM?
episodic= events from life
- time stamped
- conscious effort to recall
- several elements
semantic= facts and knowledge of the world
- not time stamped
- require conscious recall
procedural= actions or skills e.g. riding a bike
- without conscious effort
- not time stamped
Evaluate the types of LTM:
+ neuroimaging evidence
brain scan studies (Tulving) pps perform tasks scanned with PET, left prefrontal cortex semantic, right episodic, validity
+ real life application, Belleville et al, episodic memories could be improved in older people, cognitive impairment, performed better in test than control, enabling treatment to be developed
- two types (Cohen, Squire) episodic and semantic declarative (stored together), procedural non declarative
+ clinical evidence, Clive wearing, viral infection, damaged hippocampus procedural memory works, piano, lost his episodic memory, has semantic memory, remembers his wife
What is the working memory model
explains how the short term memory is organised/functions
- consists of 4 components
