Cognitive psychology

Cognitive psychology

1. models of memory

   • nature of memory
     • STM
       • Duration of STM
         • Peterson and Peterson
           • Lab experiment
           • 24 ppts
           • nonsense trigrams
           • repeated after 3, 6, 9, 12, 15 & 18 seconds
           • 90% remembered after 3 seconds
           • 20% after 9 seconds
           • 2% after 18 seconds
           • Evaluation
             • ecological validity
               • artificial stimulus- hard to apply to real life
               • does apply to verbal material
             • internal validity
               • tests displacement more than duration
         • Marsh et al
           • tested without warning
           • most forgot after 2 seconds
         • Nairne et al
           • same material across trials- avoids displacement
           • recall for as long as 96 seconds
             • information is retained unless displaced
       • Capacity
         • Miller
           • Average 7+/-2
         • Jacobs
           • Digits- 9.3 items
             • Only 0-9 digits, 26 letters
           • Letters- 7.3 items
     • LTM