Memory - Coding, Capacity and Duration

Memory - Coding, Capacity and Duration

1. Coding

   • Baddeley
     • Different lists of words to remember
       • Acoustically similar
         • Worse STM recall
       • Acoustically dissimilar
       • Semantically Similar
         • Worse LTM recall
         • Information coded semantically in LTM
       • Semantically dissimilar
   • Evaluation
     • Artificial Stimuli
       • Low external validity
       • Can't be generalised

2. Capacity

   • Digit Span
     • Joseph Jacobs
     • Asked to recall digits in order
       • Every success means an extra digit
     • Mean span
       • Digits
         • 9.3
       • Letters
         • 7.3
   • Chunking
     • George Miller
     • Recall more
     • Group info together
   • Evaluation
     • Lacking validity
       • Jacobs study a long time ago
       • Lack adequate control
       • Possible confounding variables
       • Other studies support these results
     • Too many chunks
       • STM only has capacity of 4 chunks
   • 5-7 items

3. Duration

   • STM
     • Peterson and peterson
       • 8 trials 24 undergraduates
         • Tested different retention intervals
         • Letters and numbers
       • STM duration very short
         • Unless rehearsed
   • LTM
     • Bahrick
       • High school yearbook study
         • 15 years after graduation
           • 90% accurate
         • 48 years after graduation
           • 70% accurate
       • LTM can last a long time
   • Evaluation
     • Artificial stimuli
       • Low external validity
       • Peterson and Peterson
     • High external validity
       • Bahrick
       • Real life stimuli