How are Memory and Attention related in Working Memory?

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How are Memory and Attention related in Working
Memory?

• Elke Lange, Christian Starzynski, Ralf Engbert
• University of Potsdam

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Memory and Attention

• 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
• keeping information available
• selecting information from either the environment
  (encoding into memory) or from memory (memory
  access)
• 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
• keeping information available
• selecting information from either the environment
  (encoding into memory) or from memory (memory
  access)
• manipulation of memory representations

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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

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Why Distraction?
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Distraction is dangerous
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Distraction is helpful
? Background music instead of narcotic drugs
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Distraction can hinder and help
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Classic Paradigm
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1
2
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3
5
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Why are irrelevant stimuli disturbing?

1. Similarity-based interference
2. Problem of limited attentional capacity

e.g., Baddeley, 1986 Neath, 2000
relevant
e.g. Page Norris, 2003
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The working-memory model of Cowan (1995)

Long-term memory

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The working-memory model of Cowan (1995)

Long-term memory

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The working-memory model of Cowan (1995)

Activated part of

long-term memory

Long-term memory

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The working-memory model of Cowan (1995)

Activated part of

long-term memory

Long-term memory

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The working-memory model of Cowan (1995)

Activated part of

long-term memory

Long-term memory

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The working-memory model of Cowan (1995)

• Focus of attention
• Limited to four units (Cowan, 2001)

Focus of


attention

Activated part of

long-term memory

Long-term memory

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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)

Focus of
attention
Activated part of
long-term memory
Long-term memory
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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)
• Voluntary selection

voluntarily
Focus of
attention
Activated part of
long-term memory
Long-term memory
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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)
• Voluntary selection
• Automatic recruitment

voluntarily
Focus of
attention

1. Change in physical properties (e.g. loud noise,
   sudden movement)
2. Personal relevance (e.g. own name)

Activated part of
long-term memory
Long-term memory
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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)
• Voluntary selection
• Automatic recruitment

voluntarily

1. Change in physical properties (e.g. loud noise,
   sudden movement)
2. Personal relevance (e.g. own name)

automatically
Short sensory store
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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)
• Voluntary selection
• Automatic recruitment

voluntarily

1. Change in physical properties (e.g. loud noise,
   sudden movement)
2. Personal relevance (e.g. own name)

automatically
Short sensory store
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The working-memory model of Cowan (1995)
Central Executive

• Focus of attention
• Limited to four units (Cowan, 2001)
• Voluntary selection
• Automatic recruitment

1. Change in physical properties (e.g. loud noise,
   sudden movement)
2. Personal relevance (e.g. own name)

Short sensory store
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Predictions of the Cowan Model
change in physical properties
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Experiment 1 Auditory vs. Visual distractor

• Relevant task verbal or spatial serial recall
• Irrelevant stimuli (synchronized with
  the relevant stimuli)
• Auditory Tones
• Visual Color stripes beside the relevant frame

Tone distractor
Color distractor
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Results Experiment 1
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Summary Exp. 1

• 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) ?

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Experiment 2 Distraction by irrelevant objects?
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• 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

• Conditions Repetition or location change
• Hypotheses
• ? Distraction effect spatial task
• ? No distraction effect verbal task

demo
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Results Experiment 2
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Cowan Model
Criterion for distraction Change in physical
properties?
Distraction of verbal task by tone change
Distraction of spatial task by object location
change

• Not any changes but
• specific changes
• domain-specific effects

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Thresholds Effected by Task Set
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Modified Model
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Modified Model
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Modified Model
Threshold
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Modified Model
Modulated by voluntary control
Threshold
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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

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Memory Task Serial Recall
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Memory Task Serial Recall

• Spatial Task
• Digit location
• 5 items

• Verbal Task
• Digit identity
• 8 items

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Memory Task with Distractors
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Memory Task with Distractors
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Memory Task with Distractors
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Distractors (Exp.3)
36 trials
9 trials
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Distractors (Exp.3)

No feature overlap in color/shape Feature overlap in color/shape 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
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Repetition versus Change Trials
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Repetition versus Change (collapsed across tasks)
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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

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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?

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Record of Eye Movements
EL 1000 from SR Research Sample Rate 1000 Hz
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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

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Monitoring
Time x y 1 534 487
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Categorization of eye movements
saccade
Velocity x
Time / ms
saccade
Velocity y
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Eye Movements
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Example Trial Verbal Task
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Distractors
40 trials
8 trials
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Timing of Item Cycle
delay
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Change Locked Positions
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Memory Attenion verbal
Control Change
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Memory Attention verbal
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Verbal Task Error Types

• 8 correct items
• Digit 5
• Alternative item

• Order errors
• Item error distractor intrusion
• Item error control intrusion

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Verbal Task Error Proportions
Control
Alternative Intrusion Intrusion of Digit 5 Order
errors
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Verbal Task Proportion of Answers
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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, change1
  position)
• Control for attentional capture varies for
  different distractors
• Dissociation of visual (overt) attention and
  memory processes

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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

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Thanks for your attention!