Paper 1: Memory Flashcards
The Multi Store Model of Memory (MSM)
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Who created this model? (what year?)
Atkinson and Shiffrin (1968)
3 components of memory:
Sensory register, Short-term memory (STM) and Long-term memory (LTM)
Order of components when information passes through?
- Environmental stimuli (senses)
- Sensory register
ATTENTION - Short term memory (STM)
(maintenance) REHEARSAL - Long term memory (LTM)
How does this model present memory?
As a linear arrangement (single line/process) of unitary stores (single structures, with its own characteristics - encoding, capacity and duration).
Characteristics of Sensory Register
Capacity = Very large
Duration = limited
Coding = 5 senses
Characteristics of Short-Term Memory
Capacity = Limited, Jacobs: 7 + or - 2 (7+/-2)
Duration = Limited, Peterson & Peterson: 20 seconds
Coding = Acoustic (sound) - Baddley
Characteristics of Long-Term Memory
Capacity = Unlimited
Duration = Lifetime/years
Coding = Semantic (meaning)
Strengths of MSM
> Brain scanning techniques support of the existence of separate STM and LTM stores - Beardsley (found that prefrontal cortex is active during STM and LTM tasks).
Case study: Clive Wearing - supports the distinction between STM and LTM
Weaknesses of MSM
> Evidence contradicts the idea that STM is a unitary store (KF case study)
Evidence suggests that there are multiple types of LTM
There is an alternative model of memory, WMM, which has stronger supporting evidence
The Working Memory Model
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Who created this model? (which year?)
Baddeley and Hitch (1974)
A model of…
STM
A multi-component system which consists of…?
- Central executive
- Phonological loop
- Visuospatial sketchpad
- Episodic buffer
STM is an ACTIVE SYSTEM that allows us to work things through:
Two tasks can be carried out simultaneously in STM if they are being dealt with by different parts (e.g. PL & VSS can be used at the same time but PL & PL cannot)
Central Executive (CE)
Function: The control centre of the WMM. Allocates jobs to the slave systems (PL, VSS, EB).
Capacity: Limited capacity
Coding: sensory
Phonological Loop (PL)
Function: Temporary storage system for verbal info. Held in speech based form
Capacity: Limited capacity
Coding: Acoustica information
Phonological loop is subdivided. What are they and what do they do?
- Phonological store (inner ear) processes speech and stores spoken words we hear for 1-2 seconds.
- Articulatory control process (inner voice) processes speech production, and rehearses and stores verbal information from the phonological store.
Visuo-Spatial Sketchpad (VSS) - inner eye
Function: Temporary storage system for visual and spatial information
Capacity: Limited capacity
Coding: Visual information
Episodic Buffer (EB)
- original model was updated by Baddeley
- additional component was added (Episodic Buffer)
- EB acts as a “backup” store.
- Communicates with both LTM and the components of WMM (CE,PL,VSS)
Key study: Baddeley and Hitch (1976)
> Aim: To investigate if participants can use different parts of working memory at the same time.
Method: Conducted an experiment in which participants were asked to perform two tasks at the same time (dual task technique)
Results: As the number of digits increased in the digit span tasks, participants took longer to answer the reasoning questions, but not much longer – only fractions of a second. And, they didn”t make any more errors in the verbal reasoning tasks as the number of digits increased.
Conclusion: The verbal reasoning task made use of the central executive and the digit span task made use of the phonological loop.
Strengths of WMM
- The working memory model has replaced the idea of a unitary (one part) STM
- WMM explains a lot more than the MSM. It makes sense of a range of tasks – verbal reasoning, comprehension, reading, problem-solving and visual and spatial processing.
- applies to real-life tasks : reading (phonological loop), problem solving (central executive)
- KF case study support the WMM: KF suffered brain damage from a motorcycle accident that damaged his short-term memory. KF’s impairment was mainly for verbal information – his memory for visual information was largely unaffected. This shows that there are separate STM components for visual information (VSS) and verbal information (phonological loop).
- WMM supported by dual-task studies (Baddeley and Hitch).
Weaknesses of WMM
- There is little direct evidence for how the central executive works and what it does. The capacity of the central executive has never been measured.
- Working memory only involves STM, so it is not a comprehensive model of memory (does not include SR or LTM).
- The working memory model does not explain changes in processing ability that occur as the result of practice or time.