Memory - The Working Memory Model

Question 1

What is Baddeley and Hitch’s (1974) Working Memory Model?

Answer 1

• a model of short-term memory

- an explanation of how the short-term memory is organised and how it functions

Question 2

What is the central executive?

Answer 2

• directs attention to particular tasks
• an attentional process that monitors incoming data
• it controls the other systems by determining how resources will be allocated
• it has a very limited storage capacity (recent views suggest there may be no storage capacity at all)
• coding is flexible (modality free)

Question 3

What is the phonological loop?

Answer 3

• the phonological loop deals with auditory information and preserves the order in which the information arrives
• coding is acoustic
• capacity is about two seconds’ worth of what you can remember
• it is subdivided into:
• –> phonological store - stores the words you hear
• –> articulatory process - allows maintenance rehearsal (repeating sounds to keep them in working memory while they are needed)

Question 4

What is the visuo-spatial sketchpad?

Answer 4

• stores visual and/or spatial information when required
• coding is visual and spatial
• capacity is three or four objects
• Logie (1995) subdivided the visuo-spatial sketchpad into:
• –> visual cache - stores visual data
• –> inner scribe - records arrangement of objects in visual field

Question 5

What is the episodic buffer?

Answer 5

• added in 2000 by Baddeley to account for things that use both visual and acoustic information
• it is a general, temporary store for information, communicating with both LTM and the components of working memory
• integrates visual, spatial, and verbal information from other stores
• maintains sense of time sequencing, recording events (episodes) that are happening
• links to long-term memory
• coding is flexible (modality free)
• capacity is about four ‘chunks’

Question 6

What are the strengths of the working memory model?

Answer 6

• the case of KF supports separate short-term memory stores
• dual task performance studies support the visuo-spatial sketchpad
• the word length effect supports the phonological loop
• support from brain scanning studies
• applies to real life tasks: reading (phonological loop), problem solving (central executive), navigation (visual and spatial processing)

Question 7

What are the weaknesses of the working memory model?

Answer 7

• a lack of clarity over the central executive
• working memory only involves STM so it is not a comprehensive model of memory
• implies that all spatial information was first visual
• does not explain changes in processing ability that occur as a result of practice or time

Question 8

How does the case of KF support separate STM stores?

Answer 8

Shallice and Warrington (1970) carried out a case study of patient KF who had brain damage. He had poor STM ability for verbal information but could process visual information normally (difficulty with sounds but could recall letters/digits).

So his phonological loop had been damaged but other areas of memory were intact. This suggests there are separate visual and acoustic stores.

However, evidence from brain-damaged patients may be unreliable because it concerns unique cases of patients who have had traumatic experiences.

Question 9

How do dual task performance studies support the VSS?

Answer 9

Baddeley et al. (1975) found participants had more difficulty doing two visual tasks (tracking a light and describing the letter F) than doing a visual and verbal task at the same time.

The greater difficulty is because both visual tasks compete for the same limited resources. When doing a verbal and visual task simultaneously, there is no competition.

Therefore dual task performance activity provides evidence for the existence of the visuo-spatial sketchpad. The multi-store model of memory can’t explain this.

Question 10

How does the word length effect support the phonological loop?

Answer 10

Baddeley et al. (1975) found people have more difficulty remembering a list of long words (e.g. ‘association’) than short words. This is the word length effect.

This is because there is limited space for rehearsal in the articulatory process (probably about two seconds).

Word length effect disappears if a person is given a repetitive task tying up the articulatory process, demonstrating the process at work.

Question 11

How is the model supported by brain scanning studies?

Answer 11

Braver et al.’s (1997) participants did tasks involving the central executive while they were having a brain scan. Activity seen in the prefrontal cortex.

Activity in this area increased as the task became harder. This makes sense in terms of the working memory model: as demands on the central executive increase, it has to work harder to fulfil its functions.

So this study provides evidence that the central executive may have a physical reality in the brain.

Question 12

Why is there a lack of clarity over the central executive?

Answer 12

Cognitive psychologists suggest that the central executive is unsatisfactory and doesn’t really explain anything.

The central executive should be more clearly specified than just being simple ‘attention’. Some psychologists believe it may consist of separate components. Additionally, the capacity of the central executive has never been measured.

This means that the working memory model hasn’t been fully explained.

Question 13

Why is the working memory model implying that all spatial information was first visual a weakness?

Answer 13

Lieberman (1980) criticizes the working memory model as the visuo-spatial sketch pad implies that all spatial information was first visual (they are linked).

However, Liebermann points out that blind people have excellent spatial awareness, although they have never had any visual information. Leiberman argues that the VSS should be separated into two different components: one for visual information and one for spatial.

Question 14

Aim

Baddeley and Hitch (1976) Working Memory Model

Answer 14

To investigate if participants can use different parts of working memory at the same time.

Question 15

Procedure

Baddeley and Hitch (1976) Working Memory Model

Answer 15

Conducted an experiment in which participants were asked to perform two tasks at the same time (dual task technique) - a digital span task which required them to repeat a list of numbers, and a verbal reasoning task which required them to answer true or false to various questions.

Question 16

Results

Baddeley and Hitch (1976) Working Memory Model

Answer 16

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 increase.

Question 17

Conclusion

Baddeley and Hitch (1976) Working Memory Model

Answer 17

The verbal reasoning task made use of the central executive and the digit span task made use of the phonological loop. Therefore different parts of the working memory can be used at the same time.