how are memory and attention related in working memory?

How are Memory and Attention related in Working Memory?Elke Lange, Christian Starzynski,

Ralf EngbertUniversity of Potsdam

Memory and Attention

Elke B. Lange - Christian Starzynski - Ralf Engbert University of Potsdam

• Current models of Working Memory include a strong attentional component (e.g., Focus of attention in the WM model of Cowan, 2005, or Oberauer, 2002)

• Attention serves as a component for a) keeping information available b) selecting information from either the

environment (=encoding into memory) or from memory (=memory access)

c) manipulation of memory representations

• Current models of Working Memory include a strong attentional component (e.g., Focus of attention in the WM model of Cowan, 2005, or Oberauer, 2002)

• Attention serves as a component for a) keeping information available b) selecting information from either the

environment (=encoding into memory) or from memory (=memory access)

c) manipulation of memory representations

Memory Encoding

• Targets need to be selected• Usually: Selection of targets out

of non-target information• Non-targets = distractors to some

extend• Investigating selection processes

by manipulate and control distraction by irrelevant information


Why: Distraction?


Distraction is dangerous


Background music instead of narcotic drugs

Distraction is helpful


Distraction can hinder and help


Classic Paradigm

74612835


Why are irrelevant stimuli disturbing?

1. Similarity-based interference

2. Problem of limited attentional capacity

relevant irrelevant

relevant

relevant

irrelevant

e.g., Baddeley, 1986; Neath, 2000

e.g. Page & Norris, 2003


Long-term memory

The working-memory model of Cowan (1995)


Long-term memory

Activated part of

long-term memory



Long-term memory

Activated part of

long-term memory

Focus of

attention


Focus of attention:• Limited to four units

(Cowan, 2001)


Long-term memory

Activated part oflong-term memory

Focus ofattention

Central Executive



(Cowan, 2001)


Long-term memory


Focus ofattention

Central Executive

voluntarilyFocus of attention:• Limited to four units

(Cowan, 2001)• Voluntary selection



Long-term memory


Focus ofattention

Central Executive


(Cowan, 2001)• Voluntary selection• Automatic recruitment:


a) Change in physical properties (e.g. loud noise, sudden movement)

b) Personal relevance (e.g. own name)

automatically

Short sensory storeElke B. Lange - Christian Starzynski - Ralf Engbert University of Potsdam

automatically

Central Executive












Central Executive


Predictions of the Cowan Model

change in physical properties

items in the focus loose their activation benefit

leading to memory impairment for these items

deviation of the focus


• Relevant task: verbal or spatial serial recall

• Irrelevant stimuli (synchronized with the relevant stimuli):– Auditory: Tones – Visual: Color stripes beside the relevant

frame

Experiment 1: Auditory vs. Visual

distractor

5

17

38

Tone distractor Color distractor


Results: Experiment 1

40

50

60

70

80

90

verbal spatial%

co

rre

ct

silencerepetitionchange

Irrelevant colors

Verbal Spatial

40

50

60

70

80

90

verbal spatial

% c

orr

ec

t

silencerepetitionchange

Irrelevant tones

Verbal Spatial

♬?


• Domain-specific effect of distraction?– Distraction effect in the verbal task with

tone change– No distraction effect in the spatial task

with color change• Possible problems with the choice of the

irrelevant visual stimuli: – Maybe similarity plays a role in the visuo-

spatial domain (contingent capture: Folk, Remington, & Johnston, 1992)?

– Irrelevant stimuli outside of the visual relevant region might be not distractive (Eriksen & Eriksen, 1974; Awh & Pashler, 2000) ?

Summary Exp. 1


• Conditions: Repetition or location change• Hypotheses:

Distraction effect spatial task

No distraction effect verbal task

7

Experiment 2: Distraction by

irrelevant objects?• Relevant task: verbal or spatial• Irrelevant stimuli: visual-spatial

– Object-like– High perceptual similarity to the relevant stimuli– Inside the relevant visual-spatial region– Change has a spatial dimension

demo


40

50

60

70

80

90

verbal spatial

% c

orr

ec

t

repetition

change

Results: Experiment 2


automatically

Central Executive

Short sensory memory

voluntary

Focus of

attention

Criterion for distraction:Change in physical properties?

Not any changes but a)specific changesb)domain-specific effects

Distraction of verbal task by tone change

Distraction of spatial task by object location change

Cowan Model


Thresholds: Effected by Task Set


Time

Strength ofDiscrepancy Signal

Threshold A3

Threshold A2

t1 t2 t3

Threshold A1

Modified Model


automatically

Central Executive


voluntary

Focus of

attention

Modified Model


automatically

Central Executive


voluntary

Focus of

attention

Threshold

Modified Model


automatically

Central Executive


voluntary

Focus of

attention

Threshold

Modulated by voluntary control

Experiment 3: Contingent Capture

• What is the role of similarity?• Visual Search: Target has to be

selected top-down, location-changing distractor captures attention bottom-up

• The more similar a distractor is, the more likely he is attended to



4

9

2

70

3

Memory Task: Serial Recall

Memory Task: Serial Recall

Verbal Task: • Digit identity• 8 items


1 2 3

4 5 6

7 8 90

Spatial Task: • Digit location• 5 items


4

Memory Task with Distractors


9


Distractors (Exp.3)

2

4

0

3

79

Repetition of distractor position


2

4

0

3

79Change of distractor position

36 trials

9 trials

5K


No feature overlap in color/shape

Feature overlap in color/shape



Different category (object)

Different category (object)

Same category (verbal)

Same category (verbal-numeric)

Salient Not salient

Not salient

Not salient

5K

Distractors (Exp.3)

Repetition versus Change Trials


K 5

Repetition versus Change (collapsed across

tasks)


5K

Results Experiment 3

• Distraction of verbal task by object location change, if object is verbal

• Effect of distractor similarity ➜ Top-down modulated attentional

capture ➜ Contingent capture


Experiment 4• Target needs to be selected from

non target items (visual search)

• Target needs to be encoded into and retrieved from memory

➜Can we dissociate effects due to attentional selection and memory processes?


Record of Eye Movements


EL 1000 from SR ResearchSample Rate 1000 Hz

Why eye movements?• Usually the gaze indicates where

attention and information processing is located

• Information that is more difficult is fixated longer

• Information that captures attention captures the gaze

• Eye movements as indicators for attentional capture and information processing


Monitoring


x

y

Time x y1 534 487


Categorization of eye movements

Vel

ocity

xV

eloc

ity y

Time / ms

saccade

saccade

Fixational eye movements

Fixational eye movements

Eye Movements


Verbal

Example Trial: Verbal Task


Distractors

• No overlap of visual features (color/shape)• Categorically different• Salient

5• High feature overlap (color/shape)• Categorically identical• Highly similar distractor

2

4

0

3

79

Repetition of distractor position


2

4

0

3


40 trials

8 trials

Timing of Item Cycle


0 200

7

off

off

1000

delay

1200

end of cycle

Change Locked Positions


ChangeChange - 1

Change + 1

Control - 1Control

Control + 15

2

9

3

41 Repetition of

distractor position

2

4

0

3


Memory & Attenion: verbal

Distractor Rel. Item

ControlChange

Distractor changesposition


Memory & Attention: verbal


5

ControlChange

Distractor Rel. Item

Verbal Task Error Types


1 2 3

4 5 6

7 8 90

1 2 3

4 5 6

7 8 90

5

8 correct items

Digit 5

Alternative item

➜ Order errors

➜ Item error: distractor intrusion

➜ Item error: control intrusion

Verbal Task Error Proportions


5

Control Change

Alternative IntrusionIntrusion of Digit 5Order errors

Verbal Task: Proportion of Answers


5

Summary Exp. 4• Change of distractor position affects saccade

rate attentional capture• BUT:

– Attentional capture does not necessarily affect memory performance (verbal task, triangle, change locked position)

– Attentional capture can affect memory for events prior to capture (verbal task, digit 5, pre-change position)

– Attentional capture can be controlled for relatively fast (verbal task, triangle, change+1 position)

– Control for attentional capture varies for different distractors

• Dissociation of visual (overt) attention and memory processes


Summary

• A location-changing object captures the gaze (=attention) in both tasks

• But the distraction effect is top-down modulated and contingent on task properties

• If attention is directed to verbal properties verbal distractors are effective

• If attention is directed to spatial properties spatial information is distractive


Thanks for your attention!


how are memory and attention related in working memory?

Documents

elke lange

workingmemory model

wm model of cowan

focus of attention

strong attentional component

information available

selection of targets

control distraction