The multi-store model

Atkinson and Shiffrin 1968 A simple model A flow of information As system divided into a series of stages as information passes from one store to another in a fixed sequence Constraints at each stage in terms of: Capacity (the amount stored) Duration (the length of time) Encoding (the form in which it is stored)

The multi-store model

Sensory store Very short capacity Very short duration Huge amount of decay Short-term Limited capacity Limited duration Acoustic encoding Lots of decay Forgetting due to displacement Long-term Unlimited capacity Unlimited duration Semantic encoding No decay Forgetting due to interference

The multi-store model

How do we know which areas of the brain are involved in memory? Studying of the brain used to be limited to post mortems only.

Brain scanning techniques Images of the living brain can now be used to show which areas are active when doing certain tasks like remembering things.

Different areas associated with STM and LTM

Evidence for sensory memory Sperling 1960 BJGW KSXM PFHQ Shown for 50 milliseconds Participants could usually only recall four or five items Although they were aware they had seen more

Partial report technique Sperling trained participants to distinguish between 3 tones. Participants were instructed to recall the top row in response to a high tone, the middle row in response to a medium tone and the bottom row in response to low tone. They did not know which row they would be asked to recall.

findings Participants were able to recall 3 items on average in any of the 3 rows.

conclusion This suggests that participants would have been able to recall an average of 3 letters in any of the 2 rows.

explanation The reason why participants can only recall four items in the whole report technique is because the image of the whole fades during the time it takes to report back these four items. This suggests that items in the sensory memory store fade very quickly.

Iconic store Imagine writing your name with a sparkler. What happens?

Echoic store

GLANTZER & CUNITZ 1966 RECALL WORDS FROM A LIST OF 20. NURSE WOODS SKIRT BLUE BAG DREAM BOOK HAT RIVER SCARF APPLE SHEEP TIE WOMAN PAPER SHOE RED GRASS CLOCK TABLE

DID YOU RECALL THE FIRST FEW WORDS AND THE LAST FEW? THIS IS KNOWN AS THE PRIMACY AND RECENCY EFFECT THE FIRST FEW ARE VERBALLY REHEARSED MORE AS THEY ARE THE FIRST ONES THE LAST ONES ARE STILL ECHOING IN THE STM THE ONES IN THE MIDDLE ARE LOST THIS SUPPORTS THE IDEA OF A SEPARATE SHORT-TERM MEMORY THAT USES VERBAL REHEARSAL

evaluation Evidence supports separate stores Makes sense Provides a starting point for studying memory Over simple There are different types of memory e.g. procedural, episodic so maybe more than 3 stores Doesn’t explain how we sometimes remember things without rehearsal