Multi-Store Memory Model

Outline the Multi Store Model of Memory (processes)

• proposed by Atkinson and Schiffrin

• proposed first model/cognitive explanation as it was previously biological. stores are linked by processing

• linear model

• stimulus from the environment is registered by the sensory register, which has stores for all the senses

• if a certain stimulus has caused attention, it will be moved to the Short Term Memory

• through maintenance rehearsal, information in the STM can be kept there for longer

• Through prolonged rehearsal, that memory will be transferred to LTM

• memories from the LTM can be retrieved to the STM

• memories can be forgotten at any point

biologically

• sensory information is transported by neurons in the cortex and travels to the hippocampus. transported back to the cortex for permanent storage

Outline the MSM (stores)

• Atkinson and Schiffrin

• passive stores

• proposed first model/cognitive explanation as it was previously biological. stores are linked by processing

Sensory register

• coded modality specific

  • e.g. echoic (auditory), iconic (visual), haptic (tactile), gustatory (taste), olfactory (smell)

• capacity is very large - millions of receptors involved

• duration- less than half a second

STM

• coded acoustically

• capacity of 7±2 items

• duration of up to 30

LTM

• coded semantically

• capacity is unlimited, information may be lost through displacement, retrieval failure or interference

• duration is unlimited

Case Studies relating to MSM

Patient HM

• Scoville

• underwent brain surgery to relieve epilepsy and the hippocampus was removed

• LTM was severely damaged

• he could not transfer any new information to his long term memory but STM was undamaged - anterograde amnesia

• Brenda Milner studied him at his home afterwards

• managed to remember a number for 15 minutes through repetition but after 5 minutes had forgotten that the test had even taken place

• previously believed that memory was monolithic and across the brain

• sensory information is transported by neurons in the cortex and travels to the hippocampus. transported back to the cortex for permanent storage - as he didn’t have a hippocampus, his memories couldn’t be consolidated and therefore eroded

• Milner also asked him to trace a third star in between the space between to concentric stars whilst looking through a mirror - she found that although he forgot the experiment took place, he improved each time

• shows MSM oversimplifies LTM store

KF

• Shallice and Warrington

• STM for digits was poor for information read out loud but his recall was significantly better when he read the information himself

• suggests MSM oversimplifies the STM store

evaluate MSM (limitations)

• artificial tasks of supporting evidence may mean that this theory may not apply to everyday life where we have to remember more meaningful information (limitation)

• elaborative rehearsal (limitation)

  • Craik and Watkins believed that elaborative information is needed to transfer information from the STM to LTM - linking this information to information already in the LTM as opposed to repeating that information

• alternative explanations (limitation)

  • WMM and types of long term memory accomadate for the oversimplification of the MSM

evaluate MSM (strengths)

• Glanzer and Cunitz (strength)

  • primacy recency effect

  • recall is stronger for words at the beginning and end of lists as opposed to the middle

  • suggests there are separate stores for STM and LTM, primacy being the LTM and recency STM - middle words were in the STM but displaced by later words

  • supports STM and LTM as explicitly presents STM and LTM as separate

• Sperling (Strength)

  • ppts were presented with 12 letters for 1/20th of a second

  • had to recall one row

  • recall for the first row was over 75% suggesting the rows were within the capacity of the SR and it is very large

  • ppts could only recall the first 5 letters, suggesting letters faded from SR before reaching STM further supporting duration of the SR

• Wagenaar (strength)

  • created a diary of over 2400 events over 6 years

  • found when tested he had 75% recall of one particular critical detail after 1 year and 45% after 5 years

  • his sense of remembering (retention judgement) was 80% after 5 years

  • therefore supports idea that LTM is potentially limitless

• Bahrick

  • 392 participants aged 17-74

  • tested for memory of old photographs and names of their school friends

  • it was found recall in matching names to faces was 90% after 15

  • 8)% after 48 years

  • suggests LTM’s duration is verly large, potentially limitless