memory

memory

1. coding

   • : the format at which info is stored in various memory stores
   • Alan Baddely (1966)
     • gave different lists of words to four groups
       • acoustically similar
       • acoustically dissimilar
       • semantically similar
       • semantically dissimilar
     • when recalling from stm they did worse w/ acoustically similar words
       • stm coded acoustically
     • when recalling from ltm (after 20 mins), they did worse w/ semantically similar words
       • ltm coded semantically
   • artificial stim
     • words have no personal meaning to ppts
     • cannot generalise
     • limited app

2. capacity

   • : the amount of info that can be held in a memory store
   • digit span
     • researcher asked to recall certain no. of digits, then adds more till ppt can't recall in the same order
       • mean no.s recalled: 9.3 items
       • mean letters 7.3 items
   • span of memory // chunking
     • george miller (1956)
       • made observations of daily practice
       • noted that things come in 7s
       • suggests spam of stm is 7 +- 2
     • : grouping sets of digits/letters together into units
     • lack validity
       • conducted long time ago
       • confounding variables not controlled
     • overestimated cap of stm
       • covan (2001)
         • reviewed other research
           • cap was 4 chunks
           • suggests lower end of millers estimate more appropriate

3. duration

   • : the length of time info can be held in memory
   • stm - margaret & lloyd perterson (1959)
     • 24 undergrads
     • students given consonant syllables to remember & asked to count back from 3 digit number
       • told to stop after different amount of time
     • findings show short duration unless rehearsed
   • ltm
     • 392 ppts aged 17-74
     • obtained highschool yearbooks
     • recall test through
       • free recall
       • photo recognition

4. multistore model of memory

   • sensory register
     • stim from environment passes into here
     • iconic memory
       • visual info
       • coded visually
     • echoic memory
       • auditory info
       • codes acoustically
     • lasts briefly
     • high cap
     • needs to be paid attention to be passed onto other stores
   • stm
     • limited cap 7+-2
     • coded acoustically
     • lasts 30 secs
     • maintenance rehearsal passes material to ltm
     • research evidence
       • baaddely
         • tendency to mix up words acoustically sim when using stm
         • shows coding ltm semantic & stm acoustic therefore seperate
     • more than one type of stm
       • stallice & warrington (1970)
         • studied patient suffering amnesia
         • stm digits poor when read to
         • stm for digits longer when read himself
   • ltm
     • potentially perm
     • unlimited cap
     • coded semantically
     • no memories recalled directly from ltm, transferred back into stm (retrieval)
     • more than one type of rehearsal
       • craik watkins (1973)
         • found prediction to be wrong
         • type of rehearsal matters
           • elaborative rehearsal needed for ltm

5. types of ltm

   • episodic
     • : recall events from lives
   • semantic
     • :knowledge of world // broad facts
   • procedural
     • knowledge on skills
   • clinical evidence
     • hm & clive wearing
       • episodic memory impaired
       • semantic memory relatively uneffected
       • procedural memory intact
       • shows that there are seperate stores
   • neuroimaging evidence
     • tulving et al (1994)
       • got ppts to perform memory tasks while under PET scan
       • episodic & semantic memory recalled from prefrontal cortex
       • increases validity

6. the working memory model

   • central executive
     • attentional processes that monitors incoming data
     • makes decisions & allocates systems to task
     • limited processing cap
   • phonological loop
     • codes acoustically
     • phonological store - words heard
     • articulatory store: allows maintenance rehearsal
   • visio-spacial sketchpad
     • visual cache: visual data
     • inner scribe: perspective
   • episodic buffer
     • temp store
     • intergrates all stores
     • maintain sense of time sequence
     • limited cap