Types of Memory

• Evidence for sensory memory

  • Sperling: chart of letters for participants to look at for 50 milliseconds
  • one condition had to recall all letters
  • one condition had to only recall one row, which row was revealed after
  • condtion 1 remembered 5 letters on average
  • condition 2 remembered 3 letters, on a row
  • shows that the capacity of the sensory register is large & short duration
• Evidence for capacity of short term memory

  • miller & Jacob’s
  • Did a study with a list of numbers, jacobs found that participants could only recall an average of 7 numbers
  • miller found that participants could either recall 7+/-2 numbers
  • capacity of STM limited & duration
• Evidence of the duration of LTM

  • Bharik did a recall & recognition test
  • 15 years: Recall - 60% , Recognition 90%
  • 48 years: recall - 30%, Recognition 80%
  • high ecological validity, could not control extraneous variables
• Baddeley found that information is coded acoustically into the STM and semantically into the LTM.
• Support of the MSM comes from Henry Marliason who had his LTM damaged, so could not process information into his long term memory, and was held in his short term memory.
• The frontal cortex is active with STM
• The hippocampus is active with LTM
• There are three memory stores; sensory, STM & LTM
• There are 3 properties of memory stores; capacity, duration & coding.
• There are two main types of coding; sensory- Acoustic & Visual - Semantic - attaching things to their meaning.
• Sensory Register:

  • Large capacity
  • Duration of 1-2 seconds
  • Codes - Sesnory
• Short-term memory store:

  • Limited Capacity
  • Limited duration
  • Either sensory or acoustic coding, mainly acoustic
• Long-term memory store:

  • Very large capacity
  • Very long duration
  • Coding - Semantic
• According to Atkinson and Shiffrin - information is unidirectional, and flows from sensory register - STM - LTM.