Memory - Multi-store Model Flashcards
Theoretical models
A representation of the way that mental processes work
Multi-store model (Atkinson and Shiffrin)
3 main parts:
Sensory register
Short term memory
Long term memory - both are unitary stores
Flows in one direction - linear model
Information from the environment is received by the sensory register via senses
Then passed to the STM when attention is paid
Can keep info in STM through maintenance rehearsal for short time
To go to LTM, needs prolonged rehearsal and retrieve the info to STM when needed
Coding (encoding)
Transforming incoming information into a form that can be stored in memory
Visually, acoustically, semantically
Duration
The length of time the memory lasts for/how long it is kept in that store before it is forgotten
Capacity
The amount of information the store can hold
Features of sensory register
Coding: according to the sense, or mode, in which it is received. Modality specific
Visual: iconic
Auditory:echoic
Duration: very short duration
Iconic = 250 milliseconds
Capacity: potentially unlimited
STM capacity
Jacob’s: Digit span task: recall numbers and the length of them increased over time
Average capacity for letters: 7.3
Numbers: 9.3
Miller: Magic number 7
Capacity of STM is 7 plus or minus 2
Chunking: to group together items so they can be stored and processed as single concepts
STM duration
Peterson and Peterson:
Recall trigrams after counting backwards in between them - time lengthened
Prevents maintenance rehearsal
Duration is 18-30 seconds
STM coding
Baddeley:
STM is predominantly coded acoustically
When sounds presented are similar, it causes acoustic confusion
LTM coding
Baddeley:
LTM coding is semantic
Mind causes confusion when words mean the same/similar thing, only pays attention to the meaning
LTM duration
Bahrick et al:
392 high school graduates from US
Aged 17-74 years old
Asked for names + pictures of classmates from yearbook
Photo recognition: graduated within 15 years - 90% accurate (recognition from photo)
Graduated 48 years ago - 70% accurate (recognition from photo)
Can last a persons lifetime (forever)
LTM capacity
Unlimited amount
Supporting MSM
Primary and recency effect:
People tend to recall items at the end of the list (recency effect) items still in STM
And items at the beginning of the list (primary effect) transferred to LTM
Items in the middle are forgotten (displaced) due to limited capacity
Suggests separate stores for STM and LTM
Patient H.M
bicycle accident - epilepsy so removed hippocampus
Unable to form any new short term memory but can remember everything before surgery
Couldn’t transfer anything from STM to LTM
Separate stores for STM and LTM
Weaknesses of MSM
Problems with research:
Use of artificial tasks - lacks ecological validity
Limits extent to which the findings can be generalised beyond the lab.
Oversimplifies LTM:
Unitary store - there are separate parts to LTM
Procedural memories (actions + motor skills), Episodic memories (personal, autobiographical memories of events), Semantic memories (fact-based memories, not personal)
Unable to fully explain ability of LTM
Oversimplifies STM:
There are separate parts of STM
KF, motorcycle accident
Damaged STM (verbal recall) only recall 2 items from STM
Recall for visual info was normal
STM has further components for visual and verbal information
