Short Term Memory

Short Term Memory

1. Capacity

   • 7+/- 2 items of information
     • Miller 1956
       • found out that most people could only repeat back between five and nine items
       • Chunking can increase the capacity of short term memory
         • ITV
         • GCSE

2. Duration

   • Peterson and Peterson 1959
     • Aim: Establish the duration of short term memory when Rehearsal is prevented
       • Conclusion: Without Rehearsal, the duration of STM is only a few seconds
         • Held up to 30 seconds
     • Participants heard a Trigram.
       • They were asked to recall it immediately or recall it after a set of retention interval
         • 3,6,9,12,15 or 18 seconds
         • During the period before recall, they were asked to count backwards in 3's from a specified number
           • To prevent Maintenance Rehearsal

3. Encoding

   • The way the information is put into each store
     • Acoustic form
   • Conard 1964
     • Aim: To establish the form in which information is encode into STM
       • Even when the information is presented visual,encoding was acoustically
     • Participants were shown a sequence of six letters
       • They were asked to write them down as the appeared,but the presentation ran to fast for them to keep. Therefore, keeping the information in STM
         • Participants often made acoustic errors, where the letters that they had seen were replaced by those that sound simular