memory

• Multi-Store memory AO1

  • Atkinson and Shriffin (1968)
• Coding


  How information gets stored in different formats in the memory system
• Baddeley (1966) study


  1. Gave different sets of words to four groups to remember

  2. Participants shown original words and asked to recall
• Groups in Baddeley (1966) study

  • Group 1 - acoustically similar words
  • Group 2 - acoustically dissimilar words
  • Group 3 - semantically similar words
  • Group 4 - semantically dissimilar words
• When asked to recall immediately after hearing (STM recall)


  They tend to do worse in acoustically similar words
• When asked to recall after 20 minutes (LTM)


  They all did worse in semantically similar words
• The Baddeley (1966) study used artificial stimuli with no personal meaning, so it can't be generalised and has limited application with lack of mundane realism
• Capacity


  How much information can STM hold at any time
• Joseph Jacobs (1887)


  • Researched digit span
  • Participants asked to recall 4 digits in correct order, if correct researcher asked to recall 5 digits and so on until participants can't recall order correctly
  • Found mean span for digits was 9.3 and for letters was 7.3
• George Miller (1956)


  • Made observations of everyday practice (7 notes, 7 days, 7 sins)
  • Suggested the capacity of STM is +-7 items
  • Notes that people can recall 5 words
• Chunking


  Grouping sets of digits or letters into units or chunks
• AO3: lacking validity as it lacks adequate control, confounding variables weren't controlled
• It also overestimated capacity
• Cowan (2001)


  • Reviewed other research and concluded that capacity of STM was for four chunks
• Duration


  How long information remains in STM or LTM
• Peterson and Peterson (1959) study

  1. 24 undergraduate students

  2. Given trigram to remember

  3. Also given 3 digit number

  4. Asked to count backwards from 3 digit number until told to stop (prevent rehearsal)

  5. Told to stop after different amounts of time (retention interval)
• STM has very short duration unless we repeat something over and over again
• Bahrick et al (1975) study


  1. 393 participants aged 17-74

  2. High school yearbooks obtained

  3. Tested recall of people in various ways (photo recognition, free recall)

  4. Tested within 15 years of graduation were about 90% accurate in photo recognition

  5. After 48 yrs it was 60% accurate and dropping to 30% after 48 yrs
• Bahrick et al (1975) study shows the long duration of LTM
• Sensory register


  • Duration is half a second
  • High capacity
• Sensory register


  1. Pay attention to information

  2. Information goes to short term memory
• Short term memory


  • Limited capacity store
  • Coded acoustically
  • Lasts 30 seconds unless rehearsed
• Maintenance rehearsal


  1. Repeat material

  2. Pass to long term memory
• Long term memory


  • Permanent memory store
  • Unlimited capacity
  • Coded semantically
• Baddeley


  Mix up words that sound similar when we use STM and mean similar in LTM, shows that LTM and STM are different
• More than one type of STM, not a unitary store
• Shallice and Warrington, KF with amnesia


  His STM when digits read to him was poor but recall was much better when he read digits to himself
• Episodic memory


  • Ability to recall events from our lives
  • Complex, time stamped, many components, require conscious effort to recall
• Semantic memory


  • Contains knowledge to the world, facts
  • Less personal, immense collection of material
• Procedural memory


  • Memory of action or skills
  • Without conscious awareness
• Types of Long Term Memory


  • Episodic
  • Semantic
  • Procedural
• HM and Clive Wearing had difficulty recalling events that occurred to them, however their semantic and procedural memory was relatively unaffected, showing that LTM is located in different parts of the brain
• Tulving et al (1994) - neuroimaging evidence


  1. Participants perform various memory tasks while brain PET scans

  2. Found that episodic memory is located in the right prefrontal cortex and semantic memory is located in the left prefrontal cortex
• Tulving et al (1994) neuroimaging evidence


  Supports the view that there are different types of LTM
• Real life application


  • Belleville et al (2006) episodic memories improved in older people who had mild cognitive impairment, trained participants performed better on test of episodic memory after training than control group
• This enables specific treatments to be developed
• Central executive


  • Attentional process that monitors incoming data
  • Allocates tasks to slave systems
  • Limited processing capacity
• Phonological loop


  • Auditory information
  • Preserves order in which information arrived
• Articulatory control system


  Maintenance rehearsal
• Phonological store


  Stores words you hear