Short term and Working Memory- Lecture 4

Question 1

Organic amnesia & STM

Answer 1

Suggests there is a form of memory of limited duration and capacity- short term memory

Question 2

Peterson and Peterson (1969)

Duration of STM

Answer 2

18-30s- trigram memorability declined with time past 30 s

Question 3

Miller (1956)

Capacity of STM

Answer 3

7+-2 items

Question 4

Visual STM span

Corsi (1972)

Answer 4

Corsi blocks test- have to memorise the order that someone taps different blocks in a sequence- numb

Question 5

CHUNKING- STM storage

Answer 5

• Personal semantics
• Prosodic preferences-grouping into 3s
• Phonological plausibility- pronounceable?
• Expertise (e.g. language, familiar with something that is similar to words)

Question 6

STM capacity revisited

Cowan (2010)

Answer 6

range of 3-5 chunks with verbal materials in a variety of tasks

Question 7

Miller (1956) digit span- criticism

Answer 7

Researchers have suggested that in the digit span of Miller, people may rehearse (covertly) and combine individual items into chunks.

Question 8

Storage capacity of visuospatial STM revisited

Answer 8

Accuracy of scores for different array sizes shows a big drop off when array size exceeds 4 items- we store integrated objects (e.g. purple square in right corner)
How do we integrate the elements?

Question 9

The multi-store model of memory

Answer 9

Atkinson & Shiffrin (1968)
A serial sequential model- transferring info from one box to another
Main function of store is to rehearse info until it is retained in LTM
Completely wrong?- disproven year after…yet still prominent

Question 10

Warrington & Shallice (1969)

Answer 10

Neuropsychological evidence:

• Patient KF- impaired STM- limited digit span, but normal LTM
• No transfer of information
• Parallel inputs from sensory stores go to both STM and LTM
• Doesn’t need to be subjected to rehearsal to reach LTM

Question 11

Is STM a unitary store?

Answer 11

Patient KF an others show deficits in verbal STM but not in visuospatial STM
Other patients show the reverse impairment

Question 12

Multi component model of working memory

Answer 12

Baddeley and Hitch (1974) proposed that STM is composed of three, limited capacity stores:
central executive
phonological loop
visuospatial sketchpad

Question 13

Phonological loop (inner ear)

Answer 13

Model of verbal STM- stores verbal info for a brief period
Articulatory control system-
-Rehearses sub-vocally the contents of the store to prevent forgetting.
-Converts written language into sound (phonological code) so that it can enter and be maintained in the phonological store.

Question 14

Peterson & Peterson (1959) Phonological loop rehearsal

Answer 14

The contents of the store are rehearsed to be remembered

Question 15

Evidence for phonological loop

Answer 15

Phonological code and phonological similarity effect
When words sound similar it is harder to remember them
Easier when not phonologically similar

Question 16

Evidence for PL capacity

Answer 16

Based on number of sounds we can store
Length of words affects digit span- because there are more sounds in
Increasing word length decreases number of items can hold in PL as take longer to rehearse

Question 17

Different processing mechanisms for written and spoken words

Answer 17

Ppts presented with spoken and written words and later asked to recall
Given articulatory suppression task- disabled the articulatory control process- favoured remembering written words

Question 18

Baddeley, Papagno & Vallar, (1988)

Why do we need the phonological loop?

Answer 18

PV case study could learn word pairs in native Italian, but could not learn Russian word pairs- While word pair learning relied on existing semantic links (limited need for phonological coding), foreign word learning relied on phonological processing

Question 19

Evidence for separate stores

Answer 19

Quinn and McConnell (1996)-
-Using visual or verbal interference
dealing with two different substances- one for visual info and one for verbal

Question 20

Logie (1995) different stores within VSSP

Answer 20

Visual and spatial info depend on different stores:

• Visual cache: visual info e.g. object shapes, patterns and colours
• Inner Scribe: spacial info e.g. object location and movement & also rehearses contents of visual cache

Question 21

Evidence for 2 stores for visual and spatial info

Answer 21

Klauer & Zhao (2004):

• Given a visual (remember ideogram) or spatial (remember location of a dot) memory task
• Interference tasks- visual or spatial or control
• Results showed that when type of interference task congruent to memory task, recall was worse

Question 22

Episodic Buffer

Answer 22

• Newest component
• takes elements from both phonological store and visuospatial sketch pad
• Where we store integrated forms of objects
• Capacity of 4 chunks

Question 23

Central Executive

Attentional Control system

Answer 23

Attentional control system:

• Automatic control system- for decision making in complex but habitual situation
• Supervisory attentional system- decision making in novel situations

Question 24

CE main operations

Answer 24

The CE:

• Receives input from the subsystems
• selects and evaluates streams of information
• overrides responses
• switches between tasks
• constantly monitors outcomes

Question 25

Dual task performance tests

Answer 25

Used to explore the CE- as required to switch between tasks and to inhibit previous responses

Question 26

Dysexecutive syndrome

Answer 26

Damage to the frontal lobes & also in some Alzheimers patients
Issues with executive functioning

Question 27

Alternative state theories of WM

Cowan’s (1999) Embedded processes model

Answer 27

• Working memory does not consist of separate temporary stores (buffers) but operates within LTM.
• Central executive which directs attention on specific features within LTM.
• Attentional focus may be triggered by external or internal events
• Depending on stimuli, goals and tasks, different features in different states of activation. Attention can focus to all activated items in turn

Question 28

Brain areas involved in Working memory functions

Answer 28

> Frontal lobes: executive functioning
Parietal & occipital cortices: processing and maintenance of actual stimuli (location, object, or speed specific)
-A hierarchy emerges: The PFC sends signals to posterior cortices (top-down signals) to enforce the rules and maintain goals