Stores

• Capacity of sensory memory-


  Unlimited capacity- over 100 million cells in the eye that can store data

  sperling- participants could recall letters from a 3x4 grid when flashed for 1/20th of a second suggesting a large capacity
• Duration of Sensory memory

  Less than half a second

  Sperling- iconic (visual) memories are stored for a fraction of a second

  Baddeley- echoic(sound) memories are stored for 2-3 seconds
• Coding of Sensory memory

  Modality Specific- There is a register for each sense

  Chowder-found echoic and iconic stores have different duration suggesting info is coded into different sensory stores
• Capacity of Short term memory

  5-9 items - increased through chunking info together

  Jacobs-used digital span method finding mean span for letters was 7.3 and for numbers was 9.3
• Duration of Short term memory

  18-30 seconds- can be extended through verbal rehearsal

  Peterson and Peterson-participants given a trigram to remember then a three digit number to count backwards from. After counting for 3 seconds recall was 80% and after 18 seconds was 3%
• Coding of short term memory

  Acoustic- coding is sound based, material that sounds the same can be confused when recalling

  Baddeley- 4 participants given lists of words which either sounded the same, sounded differen, meant the same or meant different. Harder to recall acoustically similar words
• Capacity of Long term memory

  Unlimited-Information we think we have forgotten may just be stored in the LTM just not accessible

  Wagenaar- recorded diary of 2400 events over 6 years and tested recall of events. excellent recall showing LTM is unlimited
• Coding of long term memory

  Semantic- based of meaning of the information therefore info with the same meaning can be confused

  Baddeley- using acoustically and semantically similar word lists found that after 20 minutes recall of semantically similar words was worse
• Duration of Long term memory

  few minutes to a lifetime

  Bahrick et al- tested students on old text books

  those tested within 15 years were 90% accurate whilst those tested after 48 years were 70%.