Global Focus on Knowledge Lecture Series“Challenging the Mind”-The Cognitive Psychology of Attention -Department of Psychology
Graduate School of Humanities and Sociology/
Faculty of Letters
The University of Tokyo
Kazuhiko Yokosawa

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Introduction
My name is Kazuhiko Yokosawa
I am a Professor of Department of Psychology,
Faculty of Letters
I took up a post at the University of Tokyo on October
1,1998Introduction
My name is Kazuhiko Yokosawa.
I am a Professor at the Department of Psychology,
the Faculty of Letters.
I took up a post at the University of Tokyo on October
1,1998.
I have a PhD in Engineering.
Before I joined the University of Tokyo, I was a SeniorResearch Scientist at NTT Basic Research Labs.

Introduction
My name is Kazuhiko Yokosawa.
I am a Professor in the Department of Psychology, theFaculty of Letters.
I took up a post at the University of Tokyo on October
1,1998.
I hold a PhD in Engineering (rather unique background).
Before I joined the University of Tokyo, I was a SeniorResearch Scientist at NTT Basic Research Labs.
I specialize in visual research – e.g., “attention” and“object recognition.”
Lately, I have become interested in “multi-modalperception” and “visual-haptic interaction” as well.

Handouts
The Asahi
ShimbunAn interview

Figure removed due tocopyright restrictions

Characteristics of a Visual System
Rapid and sophisticated information
processing ability

Characteristics of a Visual System
Rapid and sophisticated information
processing ability.
Slow and unreliable information
processing ability.

Characteristics of a Visual System
Rapid and sophisticated information
processing ability.
Slow and unreliable information processing
ability.
Are these characteristics contradictory?
→ Both reflect an information processing
process that centers on attention.

Cognitive Psychology of Attention
This is a field of study examining theprinciples of human information
processing.

What is Attention?
Every one knows what attention
is. It is the taking possession by
the mind of one out of what
seem several simultaneously
possible objects or trains ofthought.…It implies withdrawal
from some things in order todeal effectively with others.
(The Principles of Psychology, 1890)
http://en.wikipedia.org/wiki/Image:Wm_james.jpg

How to Confirm the Presence of Attention?
Visual attention is not necessarily the same
as fixing the gaze of the eye.
When you look at me, this doesn’tnecessarily mean that you are paying
attention to me.
Therefore, you can’t examine attention
simply by measuring eye movement.

How to Confirm the Presence of Attention?
Posner (1980)
A cue is given before a target is presented.

‡ http://www.neuro.uoregon.edu/ionmain/
htdocs/faculty/posner.html

Posner & Raichle: Image of Mind, 1994

How to Confirm the Presence of Attention?
Posner (1980)
A cue is given before a target ispresented.
A target could be presented on theuncued side.

Posner & Raichle: Image of Mind, 1994

Cost-benefit Method
Posner (1980)

Cost-benefit Method
Posner (1980)

CostBenefit“Cost” and “benefit” are both regarded as the effects ofattention.

Crick’s Hypothesis
Francis Crick(1916-2004)‡
http://www.srl.cam.ac.uk/history/francis_crick.html

Vision is a highly parallel system. That parallelmechanism is accompanied by the serial
mechanism of “attention.”(Francis Crick: An Astonishing Hypothesis, 1994)

Vision is highly parallel

Vision is a highly parallel system. That parallelmechanism is accompanied by the serial mechanismof “attention.”

Visual SearchThis is a typicalexperimental paradigm
in attention research.
Why is it difficult to find
Wally?

Where’s Wally? By Martin Handford

Figure removed
due tocopyright
restrictions

Pop-outsearching time

No target presented

Target presented

stimulus amountsearching time

searching time

Parallel Search and Serial Searchstimulus amountNo target presented

Target presented

stimulus amountCognitive Psychology of Attention
This is a field of study examining theprinciples of human information
processing.
Attention is a great human ability; at thesame time it also reflects the limits ofhuman ability.

Feature Search and Conjunction Search
Feature search：the search for targets defined by a single feature.
Conjunction search：the search for targets defined by theconjunction of two or more features.

Feature integration theory:
A revised version of Treisman & Gelade’s model (1980)
Recognition network
Memoryrepresentationof objects

Color map

Temporary object
representation
Time tPlace xProperties Relations
NameOrientation map

RedYellowBlue

Master map

Visual stimuli

Attention spotlight‡ http://weblamp.princeton.edu/~psych/
psychology/research/treisman/index.php

Why is Attention Necessary?
The bottleneck of information processing
Attention allows us to select necessary
information and discard unnecessary
information.

Adaptation to circumstances
By emphasizing or amplifying information
intentionally and consciously, attention helps
turn information into memory or action.

Numerical Limit of Attention (Objects Tracked)
Multiple Object Tracking
Subjects’ task is to track the indicated target itemsamong multiple (8~10) items.
All items move randomly for about 10 seconds.

Numerical Limit of Attention (Objects Tracked)
Multiple Object Tracking
Subjects’ task is to track the indicated targeted
items among multiple (8~10) items.
All items move randomly for about 10 seconds.
Subjects are able to track up to five items with 85%
accuracy.

Target Merging(Scholl, Pylyshyn, & Feldman, 2001)

Target merging makes the tracking task
more difficult.
Two items are merged into a single object.
It is difficult to attend to part of an object.
Object-based visual processing is suggested.

There is no point in arguing simply about
a numerical limit to attention.

Change Blindness
This is the phenomenon whereby a person viewing a visualscene fails to detect physical changes in a scene which seemto be visually recognizable enough, or an observer performs sopoorly in detecting change that even he/she is surprised.

The Flicker Method
Two images are alternately displayed.
There is only one difference between thetwo images.

Figure removed due tocopyright restrictions

The Cut Method
This time, you are asked to watch a video.
In the same way as in the previous
problem, you are asked to detect changes.

The Cut Method
Again, you are asked to watch a video.
In the same way as in the previous
problem, you are asked to detect changes.

Change Blindness
This is the phenomenon whereby a person viewing a visual
scene fails to detect physical changes in the scene which
seem to be visually recognizable enough, or an observer
performs so poorly in detecting change that the observer
him/herself is surprised.
Observers rarely notice the discontinuity in a dialog just bylooking at the scene once.
Even when a change is made to the central actor in a scene,
two-thirds of the observers don’t notice it.
We are not able to detect change as efficiently as we think.

Change Blindness
This is the phenomenon whereby a person viewing a visual
scene fails to detect physical changes in the scene which
seem to be visually recognizable enough, or an observer
performs so poorly in detecting changes that the observer
him/herself is surprised.
Observers rarely notice the discontinuity in a dialog just bylooking at the scene once.
Even when a change is made to the central actor in a scene,
two-thirds of the observers don’t notice it.
Experiential knowledge of filmmakers
Movies are not necessarily shot in sequence; therefore small
discrepancies in their details are common. Viewers, however,rarely notice them.

Figure removed due tocopyright restrictions
http://www.moviemistakes.com/

Change Blindness and Scene Context
Yokosawa & Mitsumatu (2003, Journal of Vision)

The effects of scene context on change
detection
Comparing a meaningful scene and ameaningless scene.

The Scene Jumbling Experiment
K. Yokosawa & H. Mitsumatsu(2003). Does disruption of a scene
impair change detection? Journal ofVision, 3, 1, 41-48.

Normal（Meaningful）

Jumble 6（Meaningless）

Jumble 24（Meaningless）

Types of change: color change, positional change, absence of objects

Change Blindness and Scene Context
Yokosawa & Mitsumatu (2003, Journal of Vision)
The effects of scene context on change detection
Comparing a meaningful scene and a meaninglessscene.

Results of the Scene Jumbling Experiment
Yokosawa & Mitsumatu (2003, Journal of Vision)
35

No significant
differenceReaction time (s)

30
25
20
15
1050

NormalJumble 6

Jumble 24

The Partial Elimination Experiment
Normal condition
Number of sections
displayed

3101724

The Partial Elimination ExperimentJumble condition
3101724

The Results of the Partial Elimination Experiment
Yokosawa & Mitsumatu (2003, Journal of Vision)
Normalconditions

Jumbled conditions

35

353030reaction time

25

25

20

20

1515

10

105

50005101520

Number of sections displayed

05101520

Number of sections displayed

Characteristics of a Visual System
Rapid and sophisticated information processingability
Recognition through rapid serial visual presentation(RSVP), pop-out

Slow and unreliable information processing ability
Change blindness, serial search→ Both reflect an information processing processthat centers on attention.

Triadic Architecture : A revised version of
Rensink’s model (2002, Ann. Rev. Psychol)

ObjectSetting information

LayoutGist

Attention
Proto-Object

Early vision

Layout：The spatial arrangement of objects in the scene
Gist：The abstract meaning of the scene

Cognitive Psychology of Attention
This is a field of study examining principles ofhuman information processing.
Attention is a great human ability; at the sametime it also reflects the limits of human ability.
Surprisingly, we don’t know much about attention.
It is a very important study area in the field ofcognitive psychology.

Mini Report
Write freely about the significance andimportance of attention.