Memory

Memory

1. Study for Duration

   • Peterson & Peterson
     • P's given nonsense trigrams, & asked to recall after either 3.6.9,12,15 or 18 secs
     • Asked to count backwards in 3's from a given number-'interference task'
     • After 3 secs, 80% correct, & after 18 secs, 10% correct
     • Very little stays in STM for longer than 18 seconds

2. Study for Capacity

   • Jacobs
     • Given a list of letters or digits
     • Had to repeat them back in the same order, which increased until they got it wrong
     • Recalled correctly 9 digits & 7 letters
     • Capacity increased with age during childhood
     • STM limited storage of 5-9 items
   • Miller
     • Argued STM is 7 +/- 2 items- Millers 'MAGIC NUMBER'
     • Use chunking to combine letter or digits together into meaningful ones
     • Can probably hold 7 pieces of 'chunked' info, increasing STM's capacity

3. Study for Encoding

   • Baddeley
     • 4 sets of words- either acoustically similar, acoustically dissimilar, semantically similar & semantically disimilar
     • Had to recall immediately or after a 20 minute task
     • P's had issues with recalling acoustically similar words immediately (FROM STM)
       • Suggests STM relies on acoustic encoding
     • If recalled after interval (FROM LTM), issues with recalling semantically similar words
       • Suggests LTM relies on semantic encoding

4. MULTI-STORE MODEL- ATKINSON & SHIFFRIN

   • Glanzer & Cunitz
     • Read out list of words to P's & asked them to recall as many as possible
     • Recalled more from start & end of list
     • Supports idea of STM & LTM being separate
     • Primary Effect--> Words heard 1st so goes in LTM. Recency Effect--> Words heard last, so recalled from STM
   • Case Study of HM
     • Operation to remove parts of brain, including Hippocampus, to try to reduce his epileptic fits
     • Couldn't form new LTMS, but still able to perform STM tasks
     • Supports idea that LTM & STM are separate

5. WORKING MEMORY MODEL-BADDELEY & HITCH

   • Shallice & Warrington
     • Case study on KF, who was a brain damaged patient
     • His STM was damaged, but his LTM normal
     • Remembers words better if presents visually as opposed to auditorally
       • Shows STM is separate to LTM, & that there is different components
   • Baddeley & Hitch
     • Based model on results from interference tasks.
       • If P's asked to perform 2 tasks simultaneously that use same system, then performance on one, or both will be affected.
     • If asked to perform 2 tasks that involve different systems, then performance isn't affect on either task
   • Bunge el al
     • Used fMRI to see which parts of brain most active when P's doing 2 tasks
     • Same area active in either dual or single task conditions
     • Significantly more activation when doing dual task

Images and files in the map