Models of Memory

Models of Memory

1. The Multi-Store Model of Memory (Atkinson & Shiffrin)

   • An information-processing approach!!!!
   • 3 Unitary Stores
     • 1. Sensory Memory
       • 95% of information dumped. Five senses provide info. Passes important info onto STM.
     • 2. Short Term Memory
       • Attention required to reach this stage. We process active info. Very limited capacity and duration. Maintenance rehearsal loop to solidify memory.
       • Capacity: 5-9 (Jacobs Digit Span Technique). Duration: 18-30s (Trigam Petersonx2). Encoding: Mainly acoustically (Baddeley CAP CAT etc)
         • AO3: Simon said depends on chunk size - larger equals lower span - therefore Miller too vague.
         • Jacobs: individual differences such as age affect span.
         • Later research found STM doesn't just encode acoustically, take longer to ackowledge a and A are same compared to A and A - visual encoding.
     • 3. Long Term Memory
       • Last stage providing lasting retention of info and skills. Information can be retrieved from STM and moved to LTM.
       • Capacity: Unlimited. Duration: Indefinite (Bahrick year book). Encoding: Mainly sematically (Baddeley 10 words).
         • Was Baddeley testing LTM? Only left 20 minutes - only applicable to 20 mins but not 5 years.
         • LTM may not encode just semantically but also visual.
   • Support from case studies: HM - parts of hippocampus removed - epilepsy. After was normal but could not form new LTMs. STMs fine. Therefore supports separate stores.
   • MSM Evaluation
     • Craik & Tulving - deeper processing improves chance of remembering - those who attached word to other things remembered more often - suggests enduring memories made by processing not rehearsal.
     • Shallice + Warrington - KF had motorbike accident, damaged STM but not LTM, suggests flow of info is incorrect.
     • MSM is too simple - dual task technique shows 2 tasks can be completed not one.

2. The Working Memory Model (Baddeley & Hitch)

   • Identified flaws with MSM, especially STM.
   • 1. Sensory Memory (same as MSM)
   • 2. Central Executive
     • Allocates tasks to three slave systems. Info processed. When it is a complex task, the CE must help relevant slave system.
     • 3. Phonological Loop
       • Deals with sound. Phonological store holds words you hear, whilst the articulatory process acts as an "inner voice" ,repeats the words on a loop to prevent them from decaying
     • 4. Visuo-spatial Sketchpad
       • Used to plan spatial tasks, info only temp. stored. Split into visual cache storing info about visual items and inner scribe storing arrangement.
     • 5. Episodic Buffer
       • Extra storage space for both spatial and auditory information.
   • WMM Evaluation
     • Baddeley supports inability to complete two same modality tasks - red light and letter angles - struggled.
     • Much research comes from brain damage patients - assumed memory only part of brain damaged - cannot be generalised.
     • Baddeley and Hitch Support explains dual task performance - showed WM can complete 2 simultaneous tasks, MSM could not.
     • Support from case studies - SC couldnt learn word pairs out loud - shows split of different modalities.
     • Central Executive too vague - are not told a lot about it therefore WMM needs development.