"マッハの本"を屏風状にした木枠図形の知覚(第23回大会 優秀発表賞抄録)

The Japanese Psychonomic Society

NII-Electronic Library Service

The JapanesePsychonomic Society

The JdPaneseJou･matofIls3,chonomic'Science

2005,Vol,24,No,1,129-130

Summary

ofAwarded

Presentation2P24

Perception

of

aframed

solid

figurereplicating

afanfold

"Mach's

book"

Hisae

ITo

Uitiversity

_of

the SacredHigart*

We

used a

framed

solid

figure

in

our experirnent

Most

ef the _participantswho observed it

perceived

differences

inbrightnesson itsthree_planes. We moved

the

figure

in

two ways,

back

and

forth,under thesame lightingconditions. The _perception of the

differences

inbrightness was changed, depending on the figurelocation.

These

perccptions of a

framed

figure

without physi-cally

defined

surface$ show the same relationships as the _perceptions of a fanfold _paper with surfaces. Therefore,itis

_plausible

toassume thata _perceptivescheme of afanfold_paper

(schematic

mediating variables} _givesa model to assirnilate a framed

figure

{perceptual

local

variables). Itcan

then

be

stated

that

the

_perception of

differences

in

brightness

is

_possib]y actualized when perceptual localvarjables are subsumed

into

schematic mediating variables.

Key words: localvariables, mediating variablcs, brightness

differences

Demoustration

and

Explanation

Itis very interesting to watch a Mach's book, which isa sheet of _paper

folded

in

two and _placed on

a

desk.

In

the right

direction

of

lighting,

the

right-hand

plane of the _paper isbright and the left-hand

plane isdark. Ifitisviewed with one eye a reversal of itsdepth can be _perceived,and _thepaper appears

to

lift.

The

right plane should then

be

dark and the

leftshould be bright because the lightingdirection

remains fixed,and

the

lightsensation remains con-stant.

But

surprisingly, the right _plane appears to

be

bright

and the

left

appears to be dark because the

brightness constancy isnot maintained This phe-nomenon isnot explained ifwe assume that

percep-tion

_is

directlydetermined

by

thestimuli.

The

book,

"Atleinson

and

Hi(gard's

introduction

to

Psychotogy"

(Smith

et al. 2003, 14th ed,) states that`'perception _is

the

use of such assumptions to

integrate

incoming

sensory information

into

a model ofthe world, based

upon which we make decisionsand take action."

(p.

149)We may follow this

definition

of _perception and

translate"sensory _information"

into

local

variables

(LVs},

and "a

model of the world"

into

mediatlng variables

(MVsL

We could then assume that

percep-tionis_possiblyactualized when LVs are subsumed

intoa $et of

MVs.

* school of Human scieiEe, university of

't'he

sac'rrreLt

Heart,4L3-] Hiro,Sibuyaku, Tokyo 15e-8938

Copyright 2005, The JapanesePsychenomic Society,Allrights reserved.

The

phenomenon of Mach's book shows

that

a set ef MVs has the _power toleadus toperceive as ifthe physical propertiesof

LVs

are changed. It

is

then

possibie to assume that this subsuming function works effective!y to make up the

deficit

of the

LVs.

Figure

1a

and

1b

are

fanfold

solid

figures

used

in

our

experiments. They copy "Mach's

book" but theLVs

have

a

deficit.

They

are made with wooden irames

and so do not have _physical surfaces and edges.

Most of the _{participantsperceived}

_planes

and white edges whichcornposedtheframedareasandaneven

brightness difference on each _plane.

We

have

as-sumed thatthese demonstrate thefunction of

MVs.

The

set of

MVs

in

our experiment act as a

hypotheti-calmode! appearing as ifitwere a substantial fanfoid paper with surfaces and edges. The _participantswho

perceived a

brightness

difference

en each plane probably applied themodel totheframed figure with-out physical surfaces and edges. This dernonstration and explanation gives us more information forother

questions. For example, when the

figure

is

moved

back

and

forth

reversib]y, under the same lighting

conditions, the _perception of a differencein bright-ness might change frernrtght

to

left,This _prediction was made forour _present

investigation,

Method

Participants The participants were

30

female undergraduate students.

The Japanese Psychonomic Society

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130

(a)

(b>

!Light

elP/Light

The

_Japanese

_Journal

o

(c)

fPsychonomic

_Science

_Vol.

Figure

1.

_<a}

Normal _position

{NP;

of brightness differenceinthe NP

(d)

24,

No.

1

IV==30}.

_(b)

Revcrse _position

_(RP;

IV,-30),

(c)

.

_(d)

Perception of the order of

brighrness

diffPerception

of the order erence

in

the RP.

height,width, and

depth,

allof

60

centimeters were used.

The

inside

walls of the

boxes

were covered with

_grey

sheets of

_paper.

(b)

Two

fixing

_pillars,one

ineach box, supported the figurewith a clip.

{c}

A

lightsource on the upper right side ef each box i]luminated equalLy the background within thc

fi-gure.

Materials The 2 solid-framed figuresillustrated

in

figures

la

and

1b

were used as

the

viewing object.

The frame of each figurewas 7centimeters inlength and _painted white.

Procedure

(a)

The

figures

were positioned

in

2

ways, so that 2 conditions were _provided.

In

the nermal _position

(NP>

the leftedge was nearer than

the right edge. In _the reversc _positien

(RP}

the Ieft

edge was more

distant

than the edge on theright.

(b>

We

randomly presented a

figure

in

either the normal _position

(NP)

or reverse _position

(RP}.

(c)

The

participantwas requested

to

compare the

difference

in

brightness of the 3 planes and to

de-scribe them inan order with thedarkest _plane first, and the brightestlasL

Results

and

Diseussion

The perception of the erder of brightness differ-ence with the figureina normal _position isshown in

Figure

lc.

The

va]ue of the erder of

brightness

was

analyzed with a Friedman test. This analysis

re-vealed that

the

average value ofthe order of

bright-ness was:

first,

the

leit

plane

(1,33);

second, the right

plane

(1.77);

and thirdthecenter

{2.90).

These

differ-ences were shown _tobe statistically significant by a

Friedman

test

(x2

=:

39.27,

P<

.O1).

The

perception of the order of differencein bright-ness with the figureinthereversed _position

is

shown

inFigure ld. The average value of the order of

brightness

difference

was shown to

be:

first

the

cen-ter

_plane

_(1.23);

second, theleft_plane

(2,13);

and third,

the right _plane

(2.63}.

These

difference$

were also statistically significant

by

a Friedman test

(x2=

27.75,P<.Ol),

Perception

by

theparticipantsof theordinal

differ-ence of brightness was statistically significant _both

in

the

NP

(normal

position)and

in

the RP

(reverse

position). These results have demonstrated that, even though the lightingcondition isconstant, the perception of

brightness

difference

can change

de-pending on the_positionof the

framed

figure.Inthe

NP, the left_plane was _perceived darkest, and the

center was brightest.Inthe RP.the center _plane was

perceived

darkest

and theright was

brightest.

These

perceptions of a

framed

figure

without _physical

sur-faces

show the same relationships as the _perceptjons

of a fanfoldpaper with physical surfaces.

Thcrefore,

itis_p]ausibletoassume thata _perceptive scheme of a fanfo]d_{paper gives}a model toassimi]ate a framed

figure.Itcan then

_be

stated

that

LVs

(local

variables) of a framed

figure

have

been

subsumed into MVs

(mediating

variables) as a_perceptual model, and

that

deficits

of the LV surfaces have been supplied, so

that subjective surfaces and brightness

differences

are perceived,

Referenee

Smith,E.E.,Nolen-Hoeksema, S.,Fredrickson,

B.

L.,

&

Loftus,G.R,2OO3

A

thinson

&

Hiigard

's

introduction