On

Making

the

Right

Choice

The

Deliberation-Without-Attention

Effect

Ap

Dijksterhuis

et

al.

Science

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H.

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Crapo

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Gallego

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Virshup

Methods

Enzymol

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Martinek

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Manoukian

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Young

Cell

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M.

Abe

E.

D.

Herzog

G.

D.

Block

Neuroreport

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C.

Iitaka

K.

Miyazaki

T.

Akaike

N.

Ishida

J.

Biol

Chem

-LRB-

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P.

S.

Klein

D.

A.

Melton

Proc

Natl.

Acad

Sci

U.S.A.

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G.

Adelmant

A.

Begue

D.

Stehelin

V.

Laudet

Proc

Natl.

Acad

Sci

U.S.A.

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W.

Doble

J.

R.

Woodgett

J.

Cell

Sci

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A.

Balsalobre

F.

Damiola

U.

Schibler

Cell

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F.

Zhang

C.

J.

Phiel

L.

Spece

N.

Gurvich

P.

S.

Klein

J.

Biol

Chem

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A.

J.

Gelenberg

et

al.

J.

Med

-LRB-

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J.

A.

Ripperger

L.

P.

Shearman

S.

M.

Reppert

U.

Schibler

Genes

Dev

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Iwahana

et

al.

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J.

Neurosci

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Benedetti

et

al.

Neurosci

Lett

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H.

Lenox

T.

D.

Gould

H.

K.

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Genet

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et

al.

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et

al.

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Biol

Chem

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M.

E.

Dokucu

L.

Yu

P.

H.

Taghert

Neuropsychopharmacology

-LRB-

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We

thank

the

University

of

Pennsylvania

Diabetes

and

Endocrinology

Research

Center

Vector

Core

-LRB-

NIH

DK

-RRB-

and

M.

J.

Birnbaum

for

adenoviruses

and

J.

D.

Alvarez

and

A.

Sehgal

for

helpful

discussions

Supported

by

NIH

-LRB-

to

M.A.L.

-RRB-

and

NIH

-LRB-

to

P.S.K.

-RRB-

Supporting

Online

Material

Materials

and

Methods

Figs

to

October

accepted

January

science

On

Making

the

Right

Choice

The

Deliberation-Without-Attention

Effect

Ap

Dijksterhuis

Maarten

W.

Bos

Loran

F.

Nordgren

Rick

B.

van

Baaren

Contrary

to

conventional

wisdom

it

is

not

always

advantageous

to

engage

in

thorough

conscious

deliberation

before

choosing

On

the

basis

of

recent

insights

into

the

characteristics

of

conscious

and

unconscious

thought

we

tested

the

hypothesis

that

simple

choices

-LRB-

such

as

between

different

towels

or

different

sets

of

oven

mitts

-RRB-

indeed

produce

better

results

after

conscious

thought

but

that

choices

in

complex

matters

-LRB-

such

as

between

different

houses

or

different

cars

-RRB-

should

be

left

to

unconscious

thought

Named

the

deliberation-without-attention

hypothesis

it

was

confirmed

in

four

studies

on

consumer

choice

both

in

the

laboratory

as

well

as

among

actual

shoppers

that

purchases

of

complex

products

were

viewed

more

favorably

when

decisions

had

been

made

in

the

absence

of

attentive

deliberation

C

ommon

knowledge

holds

that

thorough

conscious

thought

leads

to

good

decisions

and

satisfactory

choices

Whether

purchasing

a

new

car

a

desktop

computer

or

a

pair

of

shoes

people

generally

believe

that

serious

conscious

deliberation

increases

the

probability

that

they

will

make

the

Bright

-LSB-

choice

This

idea

applies

especially

to

choices

between

products

that

are

complex

multifaceted

and

expensive

Whereas

most

people

are

willing

to

buy

a

new

set

of

towels

without

much

thought

they

are

unlikely

to

buy

a

new

car

or

outfit

a

new

kitchen

without

deliberation

A

second

pervasive

idea

is

that

the

quality

of

a

choice

benefits

from

Bsleeping

on

it

-LSB-

Rather

than

-LRB-

or

in

addition

to

-RRB-

thinking

consciously

people

usually

feel

that

Bunconscious

thought

-LSB-

is

useful

for

making

sound

decisions

Whereas

conscious

thought

refers

to

thought

or

deliberation

while

conscious

attention

is

directed

at

the

problem

at

hand

unconscious

thought

can

be

defined

as

thought

or

deliberation

in

the

absence

of

conscious

attention

directed

at

the

problem

-LRB-

-RRB-

An

example

of

unconscious

thought

is

the

following

One

compares

two

holiday

destinations

-LRB-

say

the

Costa

Brava

and

Tuscany

-RRB-

and

does

not

know

what

to

decide

One

puts

the

problem

aside

and

after

hours

of

not

thinking

about

it

consciously

suddenly

the

thought

going

to

be

Tuscany

-LSB-

pops

into

consciousness

This

thought

itself

is

conscious

but

the

transition

from

indecision

to

a

preference

days

later

is

the

result

of

unconscious

thought

or

of

deliberation

without

attention

The

scientific

literature

has

emphasized

the

benefits

of

conscious

deliberation

in

decision

making

for

hundreds

of

years

-LRB-

-RRB-

The

idea

that

conscious

deliberation

is

the

ideal

-LRB-

if

not

always

attainable

-RRB-

way

to

approach

a

decision

forms

the

backbone

of

classic

-LRB-

-RRB-

as

well

as

contemporary

perspectives

on

decision

making

-LRB-

-RRB-

and

attitude

formation

-LRB-

-RRB-

In

contrast

the

notion

that

unconscious

thought

is

fruitful

hardly

developed

beyond

the

status

of

Bfolk

wisdom

-LSB-

It

has

been

postulated

or

investigated

by

scientists

infrequently

Ebut

see

-LRB-

-RRB-

The

question

addressed

here

is

whether

this

view

is

justified

We

hypothesize

that

it

is

not

First

conscious

thought

does

not

always

lead

to

sound

choices

For

example

participants

who

chose

their

favorite

poster

among

a

set

of

five

after

thorough

contemplation

showed

less

postchoice

satisfaction

than

participants

who

only

looked

at

them

briefly

-LRB-

-RRB-

Furthermore

conscious

deliberation

can

make

multiple

evaluations

of

the

same

object

less

consistent

over

time

-LRB-

-RRB-

Two

reasons

why

conscious

deliberation

sometimes

leads

to

poor

judgments

have

been

identified

First

consciousness

has

a

low

capacity

-LRB-

-RRB-

causing

choosers

to

take

into

account

only

a

subset

of

the

relevant

information

when

they

decide

-LRB-

-RRB-

Second

conscious

thought

can

lead

to

suboptimal

weighting

of

the

importance

of

attributes

-LRB-

-RRB-

We

tend

to

inflate

the

importance

of

some

attributes

at

the

expense

of

others

leading

to

worse

choices

Conversely

unconscious

thought

or

thought

without

attention

can

lead

to

good

choices

-LRB-

-RRB-

In

a

recent

experiment

participants

read

information

about

four

apartments

of

different

desirability

-LRB-

-RRB-

They

were

either

asked

to

choose

their

favorite

immediately

or

given

the

opportunity

to

choose

after

a

period

of

conscious

thought

or

distracted

for

some

time

Department

of

Psychology

University

of

Amsterdam

Roetersstraat

WB

Amsterdam

the

Netherlands

To

whom

correspondence

should

be

addressed

E-mail

a.j.dijksterhuis@uva.nl

Fig.

Percentage

of

participants

who

chose

the

most

desirable

car

as

a

function

of

complexity

of

decision

and

of

mode

of

thought

-LRB-

n

to

in

each

condition

-RRB-

Error

bars

represent

the

standard

error

SCIENCE

VOL

Fig.

Difference

in

attitude

-LRB-

on

a

scale

of

to

-RRB-

toward

the

desirable

and

undesirable

car

as

a

function

of

complexity

of

decision

and

of

mode

of

thought

-LRB-

n

to

in

each

condition

-RRB-

Error

bars

represent

the

standard

error

FEBRUARY

Downloaded

from

on

May

REPORTS

before

they

chose

In

the

third

of

these

conditions

participants

could

only

engage

in

unconscious

deliberation

They

knew

they

would

have

to

choose

later

but

the

distraction

task

prevented

them

from

devoting

conscious

attention

to

the

choice

Interestingly

unconscious

thinkers

made

better

decisions

than

conscious

thinkers

or

than

immediate

choosers

-LRB-

-RRB-

Recently

we

formulated

the

Unconscious

Thought

Theory

-LRB-

UTT

-RRB-

-LRB-

-RRB-

about

the

strengths

and

weaknesses

of

conscious

thought

and

unconscious

thought

that

is

of

deliberation

with

and

without

attention

Two

characteristics

of

conscious

and

unconscious

thought

are

important

in

the

current

context

First

conscious

thought

is

rule-based

and

very

precise

-LRB-

-RRB-

Unconscious

thought

can

conform

to

rules

in

that

it

detects

recurring

patterns

as

the

literature

on

implicit

learning

shows

-LRB-

-RRB-

However

in

order

to

actively

follow

strict

rules

conscious

attention

is

necessary

For

example

one

can

not

do

arithmetic

without

conscious

attention

This

capacity

to

follow

rules

makes

conscious

thought

more

precise

in

decision

making

because

it

can

strictly

follow

self-generated

rules

such

as

not

exceeding

a

maximum

price

Second

as

alluded

to

earlier

conscious

thought

suffers

from

the

low

capacity

of

consciousness

making

it

less

suitable

for

very

complex

issues

Unconscious

thought

does

not

suffer

from

low

capacity

Indeed

it

has

been

shown

that

during

unconscious

thought

large

amounts

of

information

can

be

integrated

into

an

evaluative

summary

judgment

-LRB-

-RRB-

These

characteristics

of

conscious

and

unconscious

thought

led

us

to

postulate

the

Bdeliberation-without-attention

-LSB-

hypothesis

on

the

relation

between

mode

of

thought

or

deliberation

-LRB-

conscious

versus

unconscious

-RRB-

and

the

complexity

and

quality

of

choice

Complexity

is

defined

as

the

amount

of

information

a

choice

involves

A

choice

between

objects

for

which

one

or

two

attributes

are

important

-LRB-

such

as

oven

mitts

or

toothpaste

-RRB-

is

simple

whereas

a

choice

between

objects

for

which

many

attributes

are

important

-LRB-

cars

or

houses

-RRB-

is

complex

Conscious

thought

is

hypothesized

due

to

its

precision

to

lead

to

good

choices

in

simple

matters

However

because

of

its

low

capacity

conscious

thought

leads

to

progressively

worse

choices

with

more

complex

issues

Unconscious

thought

-LRB-

i.e.

deliberation

without

attention

-RRB-

is

expected

because

of

its

relative

lack

of

precision

to

lead

to

choices

of

lower

quality

However

the

quality

of

choice

does

not

deteriorate

with

increased

complexity

allowing

unconscious

thought

to

lead

to

better

choices

than

conscious

thought

under

complex

circumstances

this

latter

idea

being

the

kernel

of

the

deliberation-without-attention

hypothesis

Quality

of

choice

was

operationalized

both

normatively

-LRB-

studies

and

-RRB-

as

well

as

subjectively

-LRB-

as

postchoice

satisfaction

in

studies

and

-RRB-

Study

Participants

were

subjected

to

a

-LRB-

mode

of

thought

conscious

versus

unconscious

-RRB-

-LRB-

complexity

of

choice

problem

simple

versus

complex

-RRB-

factorial

design

-LRB-

-RRB-

All

participants

read

information

about

four

hypothetical

cars

Depending

on

the

condition

each

car

was

characterized

by

attributes

-LRB-

simple

-RRB-

or

by

attributes

-LRB-

complex

-RRB-

The

attributes

were

either

positive

or

negative

One

car

was

characterized

by

positive

attributes

two

by

positive

attributes

and

one

by

positive

attributes

-LRB-

supporting

online

text

-RRB-

After

reading

the

information

about

the

four

cars

participants

were

assigned

either

to

a

conscious

thought

condition

or

to

an

unconscious

thought

condition

In

the

conscious

thought

condition

participants

were

asked

to

think

about

the

cars

for

min

before

they

chose

their

favorite

car

In

the

unconscious

thought

condition

participants

were

distracted

for

min

-LRB-

they

solved

anagrams

-RRB-

and

were

told

that

after

the

period

of

distraction

they

would

be

asked

to

choose

the

best

car

The

percentages

of

participants

who

chose

the

best

car

are

shown

in

Fig.

The

crucial

twoway

interaction

supporting

the

deliberationwithout-attention

hypothesis

was

significant

EF

-LRB-

-RRB-

P

G

Unconscious

thinkers

fared

relatively

well

and

showed

no

differences

between

conditions

-LRB-

F

G

not

significant

-RRB-

Conscious

thinkers

generally

made

the

proper

choice

under

simple

conditions

but

performed

poorly

under

complex

circumstances

EF

-LRB-

-RRB-

P

G

Study

For

the

second

study

we

made

one

change

-LRB-

-RRB-

Rather

than

asking

for

a

choice

we

asked

participants

about

their

attitudes

toward

each

of

the

four

cars

As

the

dependent

variable

we

used

the

difference

in

attitude

toward

the

best

car

and

the

worst

car

Again

conscious

thinkers

were

better

able

to

differentiate

the

quality

of

the

cars

under

simple

conditions

whereas

unconscious

thinkers

were

better

able

to

differentiate

the

quality

of

the

cars

under

complex

conditions

EF

-LRB-

-RRB-

P

G

The

means

are

shown

in

Fig.

Study

In

a

pilot

study

undergraduate

students

were

asked

how

many

aspects

of

a

product

they

would

take

into

account

in

the

purchase

of

different

products

In

this

way

we

obtained

an

average

Bcomplexity

score

-LSB-

for

different

products

-LRB-

supporting

online

text

-RRB-

For

the

actual

study

other

students

were

presented

with

this

list

of

products

From

the

list

they

were

asked

to

choose

a

product

that

they

had

recently

purchased

and

were

asked

the

following

questions

Which

product

did

you

purchase

Did

you

know

the

product

before

you

went

on

the

shopping

trip

How

much

did

you

think

about

the

product

between

seeing

it

for

the

first

time

and

buying

it

How

satisfied

are

you

with

the

product

To

test

our

hypothesis

we

distinguished

participants

who

thought

-LRB-

either

consciously

or

unconsciously

-RRB-

about

their

purchase

from

impulse

buyers

who

did

not

think

much

at

all

Hence

participants

who

indicated

that

they

bought

a

product

they

had

never

come

across

before

the

shopping

trip

were

not

included

leaving

only

participants

who

knew

the

product

beforehand

-LRB-

n

-RRB-

It

is

impossible

to

know

whether

people

are

engaged

in

unconscious

thought

by

asking

them

so

strictly

speaking

we

can

only

test

the

relationship

between

conscious

thought

Fig.

The

relation

between

mode

of

thought

and

postchoice

satisfaction

-LRB-

on

a

scale

of

to

-RRB-

for

the

six

products

most

frequently

chosen

in

study

Higher

bars

indicate

more

satisfaction

The

more

complex

the

product

-LRB-

on

a

scale

of

to

-RRB-

the

further

to

the

right

it

is

shown

The

complexity

score

is

given

in

parentheses

Participants

were

divided

into

conscious

and

unconscious

thinkers

on

the

basis

of

a

median-split

for

each

product

individually

Each

bar

represents

between

two

and

five

participants

Fig.

Postchoice

satisfaction

of

IKEA

-LRB-

n

-RRB-

and

Bijenkorf

-LRB-

n

-RRB-

shoppers

as

a

function

of

mode

of

thought

Error

bars

represent

the

standard

error

FEBRUARY

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REPORTS

complexity

and

quality

However

it

follows

from

our

definition

of

conscious

and

unconscious

thought

-LRB-

according

to

which

attention

to

the

problem

at

hand

is

the

crucial

distinguishing

factor

-RRB-

that

they

are

at

least

partly

dependent

At

any

one

point

in

time

attention

is

either

directed

at

the

decision

under

consideration

or

it

is

not

that

is

at

any

particular

point

in

time

either

you

are

attending

to

buying

a

car

or

you

are

not

The

more

you

think

about

a

decision

consciously

-LRB-

that

is

with

attention

-RRB-

the

less

time

remains

to

think

about

the

same

decision

unconsciously

-LRB-

that

is

without

attention

-RRB-

We

regressed

the

amount

of

thought

and

the

average

number

of

aspects

on

postchoice

satisfaction

As

expected

thinking

does

not

make

people

more

satisfied

nor

does

complexity

-LRB-

G

-RRB-

However

the

interaction

of

the

two

parameters

significantly

predicted

postchoice

satisfaction

Et

-LRB-

-RRB-

P

G

Correlations

were

calculated

between

amount

of

thought

and

postchoice

satisfaction

for

three

categories

of

products

complex

medium

and

simple

For

products

of

medium

complexity

no

correlation

was

found

Er

-LRB-

-RRB-

for

simple

products

a

positive

correlation

was

found

Er

-LRB-

-RRB-

P

G

and

for

complex

products

a

negative

correlation

was

found

Er

-LRB-

-RRB-

P

G

As

expected

the

more

people

thought

consciously

about

simple

products

the

more

satisfied

they

were

with

their

purchase

Conversely

the

more

people

thought

consciously

about

complex

products

the

less

satisfied

they

were

with

their

purchase

Figure

depicts

satisfaction

as

a

function

of

mode

of

thought

for

the

six

most

frequently

chosen

products

-LRB-

-RRB-

Study

On

the

basis

of

the

pilot

study

to

study

two

shops

were

selected

one

where

people

generally

buy

complex

products

-LRB-

IKEA

which

sells

mainly

furniture

-RRB-

and

one

where

people

generally

buy

simple

products

-LRB-

Bijenkorf

a

department

store

like

that

sells

clothes

clothing

accessories

and

kitchen

accessories

-RRB-

At

the

exit

shoppers

were

asked

the

following

questions

What

did

you

buy

How

expensive

was

it

Did

you

know

the

product

before

you

went

on

the

shopping

trip

and

How

much

did

you

think

about

the

product

between

seeing

it

for

the

first

time

and

buying

it

A

few

weeks

later

the

shoppers

were

asked

-LRB-

over

the

phone

-RRB-

how

satisfied

they

were

with

their

purchases

As

in

study

participants

who

indicated

that

they

bought

a

product

they

had

never

come

across

before

the

shopping

trip

were

not

included

We

divided

participants

-LRB-

Bthinkers

-LSB-

-RRB-

on

the

basis

of

a

median-split

procedure

into

those

who

engaged

in

much

conscious

thought

-LRB-

conscious

thinkers

-RRB-

and

those

who

engaged

in

little

conscious

thought

-LRB-

unconscious

thinkers

-RRB-

As

expected

conscious

thinkers

reported

more

postchoice

satisfaction

than

unconscious

thinkers

for

Bijenkorf

products

-LRB-

simple

products

-RRB-

EF

-LRB-

-RRB-

P

G

The

opposite

was

true

for

the

IKEA

customers

-LRB-

complex

products

-RRB-

in

which

case

unconscious

thinkers

showed

more

postchoice

satisfaction

than

conscious

thinkers

EF

-LRB-

-RRB-

P

G

-LRB-

Fig.

-RRB-

In

sum

in

four

studies

we

demonstrated

the

deliberation-without-attention

effect

Conscious

thinkers

were

better

able

to

make

the

best

choice

among

simple

products

whereas

unconscious

thinkers

were

better

able

to

make

the

best

choice

among

complex

products

Among

people

who

knew

the

product

they

purchased

before

they

went

on

a

shopping

trip

the

amount

of

conscious

thought

was

positively

related

to

postchoice

satisfaction

for

simple

products

and

negatively

related

to

postchoice

satisfaction

for

complex

products

Our

aim

was

to

test

the

Bdeliberationwithout-attention

-LSB-

hypothesis

both

in

the

laboratory

and

among

shoppers

In

that

sense

it

is

important

to

view

our

set

of

studies

as

a

whole

rather

than

as

a

series

of

individual

studies

Study

has

unavoidable

disadvantages

such

as

that

the

IKEA

and

Bijenkorf

samples

may

have

differed

-LRB-

after

all

different

shops

attract

a

different

clientele

-RRB-

which

naturally

opens

the

potential

for

alternative

explanations

Therefore

study

was

done

in

order

to

Bbridge

-LSB-

the

laboratory

studies

with

study

It

has

many

of

the

assets

of

study

-LRB-

real

choices

between

real

products

with

satisfaction

as

the

dependent

variable

-RRB-

except

that

all

participants

were

students

Although

we

investigated

choices

among

consumer

products

in

our

studies

there

is

no

a

priori

reason

to

assume

that

the

deliberationwithout-attention

effect

does

not

generalize

to

other

types

of

choices

political

managerial

or

otherwise

In

such

cases

it

should

benefit

the

individual

to

think

consciously

about

simple

matters

and

to

delegate

thinking

about

more

complex

matters

to

the

unconscious

References

and

Notes

It

is

important

to

note

that

attention

to

the

problem

at

hand

is

the

crucial

distinction

in

our

definitions

of

conscious

and

unconscious

thought

Thinking

about

buying

a

new

car

while

attention

is

directed

at

possible

new

cars

is

conscious

thought

Thinking

about

buying

a

new

car

while

attention

is

temporarily

directed

elsewhere

is

unconscious

thought

This

distinction

does

not

mean

that

conscious

thought

only

comprises

conscious

processes

One

can

compare

it

to

speech

Speech

is

a

conscious

process

-LRB-

i.e.

attention

is

directed

at

it

while

one

speaks

-RRB-

but

it

is

in

part

dependent

on

accompanying

unconscious

processes

-LRB-

such

as

processes

responsible

for

syntax

or

word

choice

-RRB-

R.

Descartes

The

Philosophical

Writings

of

Descartes

-LRB-

Cambridge

Univ.

Press

Cambridge

-RRB-

J.

Locke

An

Essay

Concerning

Human

Understanding

-LRB-

Penguin

London

-RRB-

I.

L.

Janis

L.

Mann

Decision

Making

A

Psychological

Analysis

of

Conflict

Choice

and

Commitment

-LRB-

Free

Press

New

York

-RRB-

H.

A.

Simon

Q.

J.

Econ

-LRB-

-RRB-

J.

R.

Bettman

M.

F.

Luce

J.

W.

Payne

J.

Consum

Res

-LRB-

-RRB-

D.

Kahneman

Am

Psychol

-LRB-

-RRB-

S.

Chaiken

J.

Pers

Soc

Psychol

-LRB-

-RRB-

R.

E.

Petty

J.

T.

Cacioppo

in

Advances

in

Experimental

Social

Psychology

L.

Berkowitz

Ed

-LRB-

Academic

Press

New

York

-RRB-

vol

pp.

As

far

as

we

know

the

possibility

of

unconscious

thought

-LRB-

as

well

as

the

term

unconscious

thought

-RRB-

was

explicitly

used

for

the

first

time

by

Schopenhauer

who

remarked

that

One

might

almost

believe

that

half

of

our

thinking

takes

place

unconsciously

-LRB-

-RRB-

G.

Claxton

Hare

Brain

Tortoise

Mind

How

Intelligence

Increases

When

You

Think

Less

-LRB-

Harper

Collins

New

York

-RRB-

The

idea

of

unconscious

thought

was

also

studied

by

various

researchers

interested

in

incubation

processes

in

creativity

An

example

is

K.

S.

Bowers

et

al.

-LRB-

-RRB-

A.

Dijksterhuis

J.

Pers

Soc

Psychol

-LRB-

-RRB-

A.

Dijksterhuis

Z.

van

Olden

J.

Exp

Soc

Psychol.

in

press

T.

D.

Wilson

et

al.

Pers

Soc

Psychol

Bull

-LRB-

-RRB-

G.

M.

Levine

J.

B.

Halberstadt

R.

L.

Goldstone

J.

Pers

Soc

Psychol

-LRB-

-RRB-

G.

A.

Miller

Psych

Rev.

-LRB-

-RRB-

T.

N

rretranders

The

User

Illusion

Cutting

Consciousness

Down

to

Size

-LRB-

Viking

New

York

-RRB-

T.

D.

Wilson

J.

W.

Schooler

J.

Pers

Soc

Psychol

-LRB-

-RRB-

Quality

of

decision

was

operationalized

from

a

normative

perspective

One

of

the

choice

options

was

made

more

desirable

than

the

others

because

it

had

been

assigned

more

positive

aspects

than

the

other

apartments

A.

Dijksterhuis

L.

F.

Nordgren

Persp

Psychol

Sci.

in

press

The

important

distinction

between

following

rules

and

merely

conforming

to

them

-LRB-

and

the

need

for

conscious

attention

in

the

former

-RRB-

was

made

by

S.

A.

Sloman

-LRB-

-RRB-

E.

R.

Smith

J.

DeCoster

Dual-Process

Theories

in

Social

Psychology

S.

Chaiken

Y.

Trope

Eds

-LRB-

Guilford

New

York

-RRB-

pp.

Unconscious

thought

is

reminiscent

of

implicit

learning

but

there

is

an

important

difference

Implicit

learning

refers

to

aspects

of

a

task

that

are

learned

while

working

on

the

task

-LRB-

and

that

are

inaccessible

to

consciousness

-RRB-

Unconscious

thought

refers

to

thought

processes

that

take

place

after

the

encoding

of

relevant

information

A

good

example

of

this

definition

of

unconscious

thought

is

the

groundbreaking

work

by

Stickgold

and

colleagues

on

learning

during

sleep

See

e.g.

-LRB-

-RRB-

Materials

and

methods

are

available

as

supporting

material

on

Science

Online

We

found

a

correlation

between

number

of

aspects

and

amount

of

thought

-LRB-

r

P

G

-RRB-

The

more

complex

a

product

is

the

more

people

think

consciously

when

deciding

to

purchase

it

Understandable

as

this

may

be

our

analysis

suggests

that

people

should

do

the

opposite

i.e.

think

unconsciously

when

deciding

to

purchase

a

complex

product

The

correlation

between

number

of

aspects

and

price

was

also

significant

-LRB-

r

P

G

-RRB-

Expensive

products

were

more

complex

than

inexpensive

ones

A.

Schopenhauer

in

Essays

and

Aphorisms

-LRB-

Penguin

London

-RRB-

p.

K.

S.

Bowers

G.

Regehr

C.

Balthazard

K.

Parker

Cogn

Psychol

-LRB-

-RRB-

S.

A.

Sloman

Psychol

Bull

-LRB-

-RRB-

R.

Stickgold

M.

Walker

Trends

Cogn

Sci

-LRB-

-RRB-

R.

Stickgold

et

al.

Science

-LRB-

-RRB-

We

thank

E.

Neimeijer

L.

Schreers

and

R.

Wassenberg

for

help

with

conducting

study

This

research

was

supported

by

a

grant

from

Nederlandse

Organisatie

voor

Wetenschappelijk

Onderzoek

-LRB-

-RRB-

Supporting

Online

Material

Materials

and

Methods

October

accepted

January

science

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O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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