2-B-13 パッチを付加した主観的輪郭図形におけるcolor spreading現象について(2002年度 日本基礎心理学会第21回大会優秀発表賞)

The Japanese Psychonomic Society

NII-Electronic Library Service

The JapanesePsychonomic Society

TheJopangsa"mrnal of Rs'),chonomicScience

20D3,VoL 22,No.1,47-48

Prizewinner's

Summary2-B-13

An

illusorycolor

spreading

effect

in

a

subjective

with

elliptic

_patchest

Tsuguya

SHiMizv*

and

Yasuko

UEMuRA**

Chiba University'･'*

contour

figure

Inthisstudy, we analyzed theconditions foranew coler spreading effectobserved ina Varin's

subjective contour

figure

with elliptic patches

{Figure

la). The effect involved a wide color

spreading without clear subjective contours, and thus itdifferedfrom

the

spreading effects studied

so far,The resu]ts of our experiments showed that

₍₁₎

the amount of spreading was found tofollow

inverted-U

functions

of the

line

width;

(2)

the

illusory

color spreading effect was _perceived both in open and closed

figures;

(3)

theeffect was not _perceived

in

a red _patch condition, although itwas

perceived

in

a _{gray patch} condition. The results suggestcd

that

thiscolor spreading effect was not

related tosubjective contours, and

that

it

differed

from theeffects reported

in

the past.

Key

words:

illusory

color $preading, subjective contour, Varin'sfigure

Introduction

We

report on arecently

discovered

color spreading

effect. This effect was observed ina Varin's

subjec-tivccontour figure

(Varin,

1971)with ellipticpatches

(Figure

la). Most of the studies _publishcd to

date

have

been

concerned with aclear subjective contour,

e.g. neon color spreading, Ina

few

studies dealing with an ambiguous contour, the_generated spreading was confined to a small loca]area, such as a neon

flank.

In

our _presentstudy we analyzed various

con-ditions

infiuencing

spreading incolor spreading

ef-fectsinvolving both ambiguous contours and wide

spreading.

Experiments

We periormed threeexperiment$. InExperirnent 1,

we examined

illusory

color spreading

in

relation

to

thefiguretype,

line

width, and _patch size, In

Experi-t_{Part of this research was conducted by Kayo}

Funakoshi in1999 under the supervision of the

second author.

*

_Graduate

_School

_of

_Science

_and

_Technology,

Chiba

University,

1-33

Yayoi-cho,

Inage-ku,

Chiba

263-8522

**

_Department

_{of Psychology, Division of}

ioralSciences,Faculty of Letters,Chiba

sity, 1-33 Yayoi-cho, Inage-ku,Chiba 263-8522

(Current

affiliation:

Graduate

School

of

Human

Life Sciences,Showa Women's University, 1-7

Taishido,

Setagaya-ku,

Tokyo

154-8533)

ment 2,we exam{ned

Musory

color spreading

in

relation to the figuretype,thc type of overlapping,

line

width, and patch size. In Experirnent 3,we

examined illusorycolor sprcading inrelation to the

patch color,

background

color, and

line

width,

Method

Subjects Each of Experiments 1and 2 were

per-formed with 5observers and Experiment

3

was

per-formed with 4 observers.

Apparatus

All

of the stimuli were presented on a

CRT display.

Stimuli

The stimuli consisted ofa

Varin's

subjec-tive contour

figure

and eight elliptic _patches. In

Experiment

1,we used stimuli which combined

dif-ferent

levelsof the figuretype

_(open

figurevs.closed

figureLlinewidth

(seven

levels),and _patch size

(three

levels).

For

a comparison, we used stimuli with only

patches and a Kanizsa Square with patches, In

Ex-periment 2, we used stimuli which combined the

levels

of

the

figure

type

(open

figure

vs. closed

fig-ure), the type of overlapping

_{('Lcompletely}

transpar-ent" vs, "transparent"), linewidth

(seven

levels).and

patch size

(two

levels).In Experiment 3,we used

stimuli which combined the levelsof the _patch color

{gray

and red),

background

color

(white

and

black),

and linewidth

{five

]evels).Figures la,lb,lc,and ld

show some oi the stirnuli used,

con-The Japanese Psychonomic Society

NII-Electronic Library Service

The JapanesePsychonomicSociety

48 The

_Japanese

_Journal

of Psychonomic

Science

Vol.22,

No,

1

@

@

@@4

;3

I,

ft

bl

@

(o

@

@

S

@

-O-OPEN-FIGURE +CLOSED-FIGURE i KnNIZSH SQUARE Q PRTEH ONLY L

ld

@

&04

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I,:1

bl@

@ @

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+OPEN-FIGURE

-O-DPEN-FIGURETRHNS,

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lt

1

O O.d O.2 O.3 O.4 o o.- O.2 O.3 O.4 O.5

LINE WIDTH _(DEGREE) LtNE-IDTH

(DEGREE)

Figure

1,

(a),

(b},

(c),

and

(d)

are thetypes of stimuli used

in

thisstudy.

(a}

is

an open

figure

with "completely transparent" gray patches.

(b>

is

a closed

figure

with i`completely transparent" gray patches.

(c}

isan opcn figurcwith

"transparent"

_{gray patches,}

(d)

isa closed figurewith "transparent"

gray patches.

{e)

is_partof

the

results of

Experiment

1,

{f)

is_partef the results of Experiment 2,

ducted ina darkroom. The observers

_judged

the

amount of the illusorycolor spreading effect of each

stimulus presented on a

CRT

display

by

using a

rating scale _procedure.

Results

and

Discussion

In Experiment 1 the amount of spreading was

found

to

follow

an

inverted-U

functjon

of the

line

width, The patch size was not related tothe

spread-ing effects,

A

similar

illusory

color spreading effect

was perceived in the open

figure

and the closed

figure.

A

stirnulus with only

_patches

didnot

_produce

the perception of an

illusory

color spreading effect.

InExperiment 2,

the

perceived effects of the linc

width and the _patch size were the same as in

Experi-ment 1.

The

typeof overlapping was not

found

tobe related tothespreading effects,

InExperirnent

3,

in

both

the

black

background

and

the red patch condition, and unlike the condition

when a white

background

was used, theamount of

spreading was not an inverted-U function ef

the

line width.

It

has

been

suggested that

in

a

Varin's

figure

the clarity of thesubjective contours isrelated totheline width

(Lesher

& Mingolla, 1993). In the _present

study, theresults showed thatthe amount of spread-ing was an inv¢rted-U function of the linewidth,

These

results suggest thatthere may

be

some

rela-tionship

between

the

illusory

color spreading and

the clarity of thesubjective contours.

However, as theillusorycolor spreading was

per-ceived

in

a closed

figure

without a subjective

con-tour,as well as

in

the open

figure,

the spreading

found inthe_present study may not be related tothe

subjective contour.

In

addition,

the

spreading

tended

to

be

different

not only

in

the chromatic condition

and the achromatic condition, but also inthe white

background condition and the black background

condition,

We

therefore

believe

that the

illusory

color spreading reported

in

the present study

is

dif-ferent

from

the other spreading effects which have been studied.

References

Lesher,

G.

W,,

&

Mingolla,

E,

1993 The rQle of edges

and line-endsinillusorycontour formation. Vision

Research,33,2253-2270.

Varin, D. 1971 Fenomeni dicontrasto e diffusione

cromatica nell'organizzazione spaziale

del

campo