Short term model

• Short Term Memory is a unitary store
• Maintenance rehearsal prevents decay
• Capacity 


  7 +/- 2 (Stores 5-9 things before forgetting)
• Duration 


  18-30 seconds
• Encoding 


  Acoustic
• Peterson and Peterson - Duration study

  Presented participants with trigrams (eg, LDP, YDG) and asked them to recall after varying materials

  Found that when rehearsal is prevented (by counting backwards task), accuracy of recall reduces
• Peterson and Peterson - Weakness

  Lack of generalisability

  • No ecological validity - lab study
  • No population validity - All American college students
• Peterson and Peterson - Strengths

  Standardised Method - Reliable

  Positive Applications - Understanding of learning

  Lab setting allows control over extraneous variable

  No ethical issues or risk
• Miller -Capacity Study 


  Participants are shown a list of numbers, then its taken away and they’re tasked to remember

  Repeated many times with one number added each time

  Found brain can only remember 5-9 things at once