memory content Flashcards
what is the capacity, duration and encoding of the sensory store
cap: 9-18 items
duration: 250ms
encoding: modal specific
what is the capacity, duration and encoding of the short term memory (STM)
capacity: 5-9
duration: 18-30 secs
encoding: acoustic
what is the capacity, duration and encoding of the long term memory (LTM)?
capacity: unlimited
duration: unlimited
encoding: semantic
who created the multi store model? (MSM)
Atkinson and Shiffrin
how is information lost from STM and LTM?
displacement and decay
outline Peterson and Peterson’s trigrams study on duration of STM
3 nonsense letter trigrams show
They had to count back in 3s from
300 = no maintenance rehearsal.
The counting increased in 3 sec
intervals (3,6,9, up to 30 secs)
They found around 90% of trigrams
were remembered after 3 seconds,
5% after 18 seconds.
Duration STM = 18-30 secs.
outline evaluation points for P+P’s trigrams study
standardised procedure apart from change in length of maintenance rehearsal = high causation ensures its only looking at STM duration and not LTM.
lacks EV - mo semantics or consequence
describe Bahrick’s study on duration of LTM
50 photos shown from school yearbook.
Asked to match name to photo or free
recall.
Results:
Up to 15yrs -
• 90% accuracy matching
• 60% on free recall.
After 48 yrs -
• 60% recall matching
• 30% free recall
describe Baddeley’s study on encoding of LTM and STM
4 conditions:
Acoustically similar & dissimilar.
• Recalled immediately
• Recalled after 30 min
Semantically similar & dissimilar.
• Recalled immediately
• Recalled after 30 min
Results:
Acoustically similar sounding words (cat, hat etc) were confused on immediate recall.
STM = acoustic encoding.
Semantically similar words (e.g big, large
etc) were confused after 30 min recall.
LTM = semantic encoding.
describe Jacob’s digit span technique study on capacity of STM
Gave pps letters, numbers of words and increased them by one each time.
Asked them after each increase to immediately recall strings of letters/numbers.
Found that people could generally recall between 5-9 items. Chunking letters could increase capacity.
outline the points for MSM A03
Research Support for Duration of STM
- P+P trigrams
Research support high in ecological validity - clive wearing
Criticism of MSM it is reductionist (oversimplified STM and treats humans like computers) elaborative rehearsal?
describe episodic memory
Personal Autobiographical experiences
Strengthened by emotions at the time
Time-stamped, place and context of
memory also included (e.g. birthday)
Explicit Memory
Least resistant to forgetting
Areas of the brain: Right PFC
describe semantic memory
General Knowledge
Facts, meanings, concepts about our world
Knowledge had by many rather than personal experience. (e.g. capital of Paris)
Explicit Memory
Less resistant to forgetting
Areas of the brain: Left PFC &
hippocampus
describe procedural memory
Skills acquired through practise
Automatic memories
Knowledge of motor movement tasks (e.g. riding a bike)
Implicit Memory
Very resistant to forgetting
Areas of the brain: cerebellum,
caudate nucleus & motor cortex
describe Tulving’s study on LTM
PET scans, 6 pp’s performing
memory tasks.
Injection of radioactive traces of gold.
More blood flow to anterior (front) = episodic.
More blood flow to posterior (back) = semantic.
describe the case study of Clive wearing in relation to MSM
herpes virus damaged his ability to have
maintenance rehearsal.
only had a STM of up to 10 secs.
supports the MSM as it proves that we do need to maintenance rehearse information in STM, as without it Clive could not form long-term memories.
describe the case study of Clive wearing in relation to LTM
lost episodic memories, but retained some semantic (recalled wife) & full
procedural memories, e.g., how to play
piano.
Proves that there are different types as
each type was affected to a greater or
lesser extent. If one type of LTM then all
would be affected to same extent.
could argue playing piano is episodic as was a concert pianist and maybe recalling memories of playing the piano to play. Also required knowledge of reading music (semantic). - can’t generalise as very diff profession
what are the components of the working memory model?
central executive
phonological loop (PL store, articulatory loop)
visio-spacial sketchpad (inner scribe, visual cashe)
episodic buffer