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PREDICTING
INDIVIDUAL DIFFERENCES
IN DISTRACTIBILITY
by Deborah June Aks
B.A., The S t a t e U n i v e r s i t y at
Binghamton, N.Y.,
o f New York 1984
A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS in THE FACULTY OF GRADUATE STUDIES DEPARTMENT OF PSYCHOLOGY
We a c c e p t to
The
this
t h e s i s as conforming
the r e q u i r e d
University
standard
of B r i t i s h
Columbia
December, 1988
©
Deborah June A k s , 1988
In
presenting
degree freely
this
at the
thesis
in
partial
fulfilment
of
University
of
British
Columbia,
I agree
available for
copying
of
department publication
this or of
reference
thesis by
this
his thesis
permission.
Department The University of British Vancouver, Canada
DE-6 (2/88)
for
and study. scholarly
or for
her
I further
purposes
representatives.
financial gain
the
requirements that
agree
may
be
It
is
shall not
that
the
Library
an
advanced
shall make it
permission for
granted
by
understood be
for
allowed
the that
without
extensive
head
of
my
copying
or
my
written
ii
Abstract Little
is
distractible problem
while
by
arousal,
known
distractors
during
to screen
how
one
of various
subjective
will
a speeded
distractibility.
report
respond
to
v i s u a l search
The
under
predictor
of
subexperiment
f o r purposes of of s t a t e
susceptibility
to
which
turned
These
findings
individual
i s one who
Type A b e h a v i o r
variables
as
presence
of
task.
The
inability
of the targeted used
here,
as
task
involving
was a d m i n i s t e r e d
t o 308
a
Each
separate
clarity. arousal
were
as w e l l
as
ineffective The
subjective
p r e d i c t o r s of
results
were
more
p e r s o n a l i t y and i n t e l l i g e n c e v a r i a b l e s
o u t t o be e f f e c t i v e p r e d i c t o r s indicate
personality,
the
treated
distractibility.
for specific
individual
distractor conditions.
is
and t r a i t
distractibility
encouraging
conditions,
distractibility
Measures of
search task
v i s u a l and a u d i t o r y
one
study approaches t h i s
out s t i m u l i which a r e independent
subjects
and
makes
i s not. This
and
m a t c h i n g under s p e e d e d
reports
what
the e f f e c t i v e n e s s
intelligence of
item
another
assessing
predictors
defines
about
that
the prototype
t e n d s t o be h i g h e r
patterns
of d i s t r a c t i b i l i t y .
and lower
of a
distractible
i n obsessive/compulsive
in intelligence.
iii
Table
Title
of Contents
Page
i
Abstract Table
ii
of Contents
List
of Tables
List
of Figures
i i i vi v i i
Acknowledgements
vii i
Chapter
1: I n t r o d u c t i o n
1
Chapter
2: The d i s t r a c t i o n
task
Is d i s t r a c t i o n
.9 generalizable?
The makings o f a d i s t r a c t o r
15
Method
18
The d i s t r a c t i o n Results Chapter
9
3: S u b j e c t i v e
test
18
& Discussion
21
report
of
distractability:
A p r e d i c t o r of d i s t r a c t i b i l i t y ? Method Stimulus Results
26 28
S e l e c t i v i t y Inventory & Discussion
28 ....31
iv
Chapter
4:
Arousal: A p r e d i c t o r of d i s t r a c t i b i l i t y ? Arousal
defined
Physiological Varying
35
basis
of a r o u s a l
36
responses to s t i m u l a t i o n :
Habituation Arousal,
and
o r i e n t i n g r e s p o n s e . . . 37
distraction
Information Response
rate
&
performance...39
- arousal
- arousal
Yerkes-Dodson
theory....40
theory
41
law
41
Measuring a r o u s a l
43
Method
46
Results Chapter
35
& Discussion
47
5: P e r s o n a l i t y : A p r e d i c t o r of d i s t r a c t i b i l i t y ?
51
Extraversion/Introversion
51
Sensation
53
Seeking
Obsessive/Compulsive Type A/
behavior
Type B p e r s o n a l i t y
Method
54 55 58
E y s e n c k P e r s o n a l i t y I n v e n t o r y . . . . 59 Sensation
Seeking
Scale
Obsessive/Compulsive
Inventory...61
Framingham Type A I n v e n t o r y Results
& Discussion
59
61 62
Chapter
6:
Intelligence: A predictor
of d i s t r a c t i b i l i t y ?
66
Method
69
Wonderlic
Test
71
Spelling
72
Component A s s e s s m e n t
& Discussion
.
7: C o n c l u s i o n s
actual
....73 76
Subjective
impressions
versus
distractibility
Subjective
76
p e r c e p t i o n of
distractibility
79
Summary c o n c l u s i o n s
80
References
82
A p p e n d i x A: The D i s t r a c t i o n A p p e n d i x B: S t i m u l u s Appendix
70
Quick Test
Results Chapter
Personnel
Test
Selectivity
98 Inventory
C: T h a y e r A r o u s a l S e l f - R e p o r t
112 118
vi
List
of
Tables
Table
1:
Group p e r f o r m a n c e on
the
distraction
test...22
Table
2:
Stimulus s e l e c t i v i t y
and
distractibility
Pearson C o r r e l a t i o n s Table
3:
Arousal
and
the
32
d i s t r a c t i o n task
-
Pearson C o r r e l a t i o n s Table
4:
Distractibility
and
48 arousability -
Pearson C o r r e l a t i o n s Table
5:
P e r s o n a l i t y and
49
distractibility
-
Pearson C o r r e l a t i o n s Table
6:
I n t e l l i g e n c e and
62
number
correct
Pearson C o r r e l a t i o n s Table
7:
Generalized of
the
Table
8:
73
p r o f i c i e n c y across
d i s t r a c t i o n task
Pearson C o r r e l a t i o n s I n t e l l i g e n c e and
conditions
-
(standardized
standardized
9:
Multiple Visual Auditory
regression/
Stepwise
74
-
distractibility distractibility
General d i s t r a c t i b i l i t y Table
scores)..74
distractibility
measures - P e a r s o n C o r r e l a t i o n s Table
-
10:Stimulus s e l e c t i v i t y personality
inventory
77 and
- Pearson C o r r e l a t i o n s
79
vii
List
Figure
1: Task e x t r i n s i c
Figure
2: Sample without
Figure
3: Sample with
Figure
items
of
and
intrinsic distractors...16
from the d i s t r a c t i o n
distractors items
Experimental
test
test
present
18
from the d i s t r a c t i o n
distractors
4: P r e and p o s t
Figures
test
present arousal
and c o n t r o l
20 self groups
report 48
viii
Acknowledgements
There helping I
a
number
of
i n d i v i d u a l s who d e s e r v e
me t h r o u g h t h e h a r r o w i n g moments
would
supply
are
like of
thank my a d v i s o r
attention
contributions meaning
to
of
to
and
o f my t h e s i s
Stanley
assistance.
creativity,
experience.
f o r h i s endless
Some o f S t a n ' s
t h i s academic endeavor,
clarity,
Coren
credit for
include
scientific
greatest
teaching
me t h e
exploration,
and
humility. I
am
grateful
preliminary art
of
draft
t o Peter
Suedfeld
of t h i s t h e s i s , as w e l l
being meticulous
i n research.
Lawrence Ward f o r h i s w i l l i n g n e s s well
as f o r h i s i n s i g h t f u l And
through
thanks i t a l l .
f o r a thorough review of a
a
as f o r t e a c h i n g
I would a l s o
like
t o s e r v e on my M.A.
me t h e
t o thank
committee as
comments.
million
to
Aaron
for helping
me r e m a i n
sane
Predicting
Individual
Differences
in
Distractibility 1
Chapter
1
Introduction "My items
experience
which
I
implication attention This
James' q u o t e responsible
of
d i s t r a c t i o n and
of
measures
personality
focus
of
In screen
in
this out
impaired
and
i s to
in tasks
the
presence
Viewed by
These
p.402).
The
be
investigate
examined
measures
arousability,
i n t e l l i g e n c e . In and
in
experiences.
measures as
predict
in
that
include well
e s s e n c e , the
a
studied
discussion
of
in a task.
to
the
a as
main
individual
of
loss
than
of
ambient
Since
distraction,
relevant
to
the
we
theories
present
to
itself
in
s t i m u l i must
be
irrelevant
f o c a l i z a t i o n and
1975).
inability
It manifests
i n which r e l e v a n t
some d e f i n i t i o n s and are
refers
f r o m models of a t t e n t i o n ,
(Norman,
frequently
that
those
different orientations
psychological
study, d i s t r a c t i b i l i t y
characterized
theories
(James, 1890
Only
distractibility.
in
consciousness
to.
experience w i l l
various
irrelevant stimuli
(distractors). is
thesis
performance
processed
and
distractibility,
this
differences
i s that
distractibility.
self-report of
mind"
attend
f o r d i f f e r e n t phenomenal
between a t t e n t i o n
predict
(agree to)
shape my
link
terms may
notice,
of are
i s what I
stimuli
distractibility concentration
attention will used
problem.
begin in
is
of more
with
a
attentional
Predicting
Individual
Differences
in Distractibility 2
According process
t o Hebb (1955), a t t e n t i o n
similar
selectivity. opposite
neural
association
selection
hypothetical that
i s , of
produces
course,
the
of d i s t r a c t i o n .
of
limited
a
Successful
"Selectivity items
to
is a
of a t t e n t i o n
incoming
involves
information
will
information-transmitting
t h e problem of which occupy the organism's
capacity"
(Meldman, 1970,
p.200) . "Concentration characterizes shiftable
From
and
attention;
and d i v i s i b l e "
the
above
(Best,
i t should
in
the
material This of
attention
that
differ
ability
in to
review,
specify
the
bear d i r e c t l y The theory
involves
attended
can provide their
screen focusing
that
below
one common
feature
selectivity
should
be t h e o n l y
s t i m u l i screened out.
i n the context
o f models
potential explanations
a s t o why
degree of d i s t r a c t i b i l i t y out extraneous s t i m u l i . on
effort
i sselective,
stimulus to
i n consciousness, with unattended
limited
and
is
c h a r a c t e r i s t i c i s discussed
people of)
what
mental
1986, p . 3 6 ) .
be c l e a r t h a t
most d e f i n i t i o n s of a t t e n t i o n that
of
i t i s a focus
of
sense
focusing
or t h e ( l a c k
This w i l l
be a
those models o f a t t e n t i o n
that
mechanism o f s t i m u l u s
selectivity
and t h a t
seem t o
on t h e p r o b l e m o f d i s t r a c t i b i l i t y .
earlier
models o f a t t e n t i o n
include
(1958), Treisman's a t t e n u a t i o n
Deutsch's Late
S e l e c t i o n Theory
theory
Broadbent's
filter
(1964) and D e u t s c h
(1963) o f a t t e n t i o n .
These
Predicting
Individual
Differences
in
Distractibility 3
theories
propose
bottleneck
exists
Messages
occurs
or is
theories.
location,
characterized irrelevant described
i n the
induce
filter as
stimuli, as
characteristics
like
a
filter
information
filtered
out
feature
filter's
a
of
an
a
models
are
associated
not
the
selection
effectiveness,
regardless
in d i s t r a c t i b i l i t y .
distractible
do
in
different
inefficient
these
a
these
non-distractible
while
or
processing.
somewhere
person
p r o f i c i e n t i n s e l e c t i n g and
having
Unfortunately
in
differences
of
being
device
p r o c e s s . Where t h i s s t i m u l u s
distinguishing
can
the
point
channels are
cognitive one
selective
some
Differences
example,
a
at
in rejected
perceptual
of
that
or
might
screening
individual indifferent
specify
with e f f i c i e n t
For be out
can
be
filter.
what
individual
versus
inefficient
filters. Other
attentional
what d i s t i n g u i s h e s person
are
Rather
than
between a
viewed
as
recognize are have
filters
set
of
stimuli.
finite
perceptual for
a
task.
individual
are
or
person
analyzers,
or
of
limits our
Variations differences
"resource"
Kahneman
or
are
based.
competition
(1973) p r o p o s e d
i n which a t t e n t i o n categorize
"cognitive
limits
may
in d i s t r a c t i b i l i t y .
and
only
to a p p l y to be An
is
resources",
imposed b e c a u s e we
mental r e s o u r c e s
i n these
into
non-distractible
processes that
These p r o c e s s e s ,
insight
i n t e r m s of
model o f a t t e n t i o n
Attentional
provide
from a
defined
cognitive
amount
may
"capacity"
attention
processing
limited. a
that
having
parallel
which
a distractible
those
separate
models
any
responsible example
of
Predicting
Individual
Differences
in Distractibility 4
such
a
limitation
"the
cognitive
allocated is
infer
greater
system
i n Kahneman's
and from
control
under
our c o n t r o l "
this
that
of
non-distractible
existing
processing
or o t h e r i n t e l l i g e n c e
excitation inputs.
approach of
to,
p.42).
We
resources, are associated
with a
resource
buffer, related
capacity
increased
might
speed
or c o g n i t i v e
employed
a
within
Snyder
1982;
1980; beam
this
theories
analogy
light
that
passively
decay 1963;
the
Eriksen
internal
argue
1985).
of
efficiency
1977;
1980)
offering
irrelevant
Eriksen
&
are
Schultz, 1980;
input
1979;
of
stimuli
inhibitory
based
n e e d s t o be s u p p r e s s e d 1985).
ignored
i n unused
In o t h e r
objects
might
channels (Deutsch &
Heuden, 1981;
Allport,
no
mechanisms
specific
&
is directed
Processing
Tipper,
of
P o s n e r , Snyder
attention
In c o n t r a s t ,
representations
Der
of
A c c o r d i n g t o t h e commonly
irrelevant
levels
of
Treisman & Gelade,
i n space.
& Schultz,
i s i n terms
that a l l stimuli
( B r o a d b e n t , 1982;
moving
to r e s t i n g Van
Inhibition
& D a v i d s o n , 1980;
beam i s f a c i l i t a t e d .
1977;
While
theories
Treisman & Gelade,
theories,
Deutsch,
and
extent ( N e i l l ,
Tipper,
of
argue
(Neill,
inputs of
some
spotlight
Davidson,
t o the s t u d y of a t t e n t i o n
group to
Posner,
Broadbent,
1985).
process
and/or
memory
relevant
This
attended
like
allocation
factors.
Another
1979;
a
resources are
(Kahneman, 1973
Such
itself
that
resource capacity
individual. as
This
a greater
manifest
related
(1973) argument
f e a t u r e s a stage i n which
to process incoming s t i m u l i .
flexible
can
appears
Tipper a l l
& Chimel, of t h e s e
Predicting
Individual Differences
in Distractibility 5
theories
suggest
deficient
in
inhibiting function
facilitating
an
or
resolved
a
exists
for
may
inhibiting
be
n o t be
are i n d i v i d u a l
indirectly
measured
by
the
their
possibility
distractibility. how
one
(1984)
individuals.
t o recognize
their
& Hemsley
i n i n h i b i t o r y mechanisms i n i n f o r m a t i o n
in distractible
of
to
an
i s open t o d e b a t e and w i l l
which
a deficit
terms
as
process,
of i n d i v i d u a l d i f f e r e n c e s , B u l l e n
i s important
provide
focusing
isa
F o r example, by p l a c i n g t h e i n h i b i t o r y models i n
that
processing
i n p u t s or
Whether d i s t r a c t i b i l i t y
process
variables
context
It
input.
of relevant
however e x c i t a t i o n and i n h i b i t i o n
performance.
suggested
i n d i v i d u a l i s one who i s
the processing
excitatory decay
here,
difference
the
a distractible
irrelevant of
process
that
ability
that
that
t o focus
individuals will a t t e n t i o n , hence
Unfortunately
might
t h e s e d i f f e r e n t models do
discriminate
differ in
i n terms o f
they a r e not very
specific
between a d i s t r a c t i b l e and
non-distractible individual. Much be
is
theorized
useful
in
our
individual
to
process
irrelevant
context
activity: which
1)
matches
about a t t e n t i o n
present
we
problem.
some may
stimuli view
i n general, F o r example in
this
the
i f we a s k an
presence
task
target.
predictions
about
dual
modality
of
presentation.
complex;
for
instance,
Several
task
theories
performance
The m o d a l i t y
some t h e o r i e s
o f an
as a dual
I g n o r e t h e d i s t r a c t o r s and 2) S e l e c t the
which might
task
the response make
depending
specific on
the
interactions are often
suggest
that
performance
Predicting
Individual Differences
in
Distractibility 6
interference same
can
modality
tasks
are
Eriksen,
and
the
important
differs
cognitive
processing
regardless resource.
single
of
According
tasks are
faci1itation
to
presented
can
occur
modalities
i n the
i f the
(Wickens,
the
in
two 1984;
single
if
then
non-distractible
will
this
between
In e f f e c t ,
same e f f e c t ,
we
are
saying
instance, a d i s t r a c t i b l e
by
visual
distractibility difference
be
variable,
viewed perhaps
and
upon t h e
be
If t h i s
highly
any
modality
and
the
that
t h a t when d o i n g
fairly
1973).
expect
in
task
size
is and
of
an
distracting
r e g a r d l e s s of t h e i r
a
has
distractible
This suggests
as
task
intra
distractor
will
same
differences
o n l y on
of
a l l stimuli,
would not
between
individual
pool
(Kahneman,
inter
of the
resource
of the
individual
auditory distractors. may
modality
would depend
resource.
for
and
to
modality
individuals
have t h e
draw
tasks
distinguishing
single
hence
c a p a c i t y v i e w we
logic
the
two
stimulus
i s o n l y one
must
t h a t the
performance
distractibility,
individual's
modality,
focal
multiple
available,
of
and
versus
models, t h e r e
capacity or
distractor
single
resource
performance
Extending
unimportant
of the
would s u g g e s t
on
difference
input.
two
separate
for
source
This
impact
stimuli
in
modality
In
tasks.
the
1985).
models.
no
if
performance
presented
Whether are
occur
source
a visual
of
task,
equally effected i s the
general
case,
then
individual
correlated
across
situations. In
contrast,
the
multiple resource
perspective
(Norman &
Predicting
Individual Differences in
Distractibility 7
Bobrow, of
1975;
Wickens,
differentiated
resources;
distractibility. specific, The test
which
task.
are where
i n favor
i s p r e d i c t e d t o be
expects greater of
occurs
resources
the
and
deplete
resource
reasoning
the
resource.
t h e same m o d a l i t y because
the
as t h e
task
f r o m t h e same p o o l . are
pools.
and In a
in different
When we a p p l y
this
to differences i n d i s t r a c t i b i l i t y ,
possibility
that
distractibility
capacity
b u t a l a r g e a u d i t o r y p r o c e s s i n g c a p a c i t y m i g h t be v e r y
irrelevant its
auditory
name
attentional
guidance
of
inputs
stimuli.
suggests,
manifestation
Since
visual
would
but
with
show
a limited
be
specific.
by
an i n d i v i d u a l
might
modality
distracted
Thus
modality
interference in a
distractors
separate
pools
degrees of
behaves a s a s e p a r a t e
distractors
task
of m u l t i p l e
perhaps d i f f e r e n t
consuming
they
suggests
view
interference
modalities, multiple
modality
resource
This
situation
it
each
contains
distractors
with
Here p e r f o r m a n c e
where
multiple
1984) a r g u e s
little
effect
The m u l t i p l e r e s o u r c e
in
any
one
or
for
t h e o r y as
argue t h a t d i s t r a c t i b i l i t y
limitations
visual
c a n be a
a l l of
the
resources. the a t t e n t i o n a l
models t h e m s e l v e s do n o t p r o v i d e
a s t o why some i n d i v i d u a l s a r e d i s t r a c t i b l e
much
and o t h e r s
are
n o t , p e r h a p s some v a r i a b l e s which a r e presumed t o be r e l a t e d
to
attention
theory of
be
more
useful.
i n c o r p o r a t e s a r o u s a l and e f f o r t
attention
domains.
will
and
we
F o r i n s t a n c e , Kahneman's into
know t h a t i n d i v i d u a l s
the resource do d i f f e r
theory
i n these
Predicting
Individual
Differences
in
Distractibility 8
The
rationale
behind
clusters
of
related
to a t t e n t i o n a l
predictors set
of
of
since
empirical
clarity,
tests
predict
will
of
which
which are
be
bases. of
In
the
In of
variables not.
will
essence,
of
valid
look
at
seem t o
be
prima-facie,
justified
might
in a
be
Each
separate
upon d i f f e r e n t t h e o r e t i c a l for purposes
of
t h e s e s e p a r a t e measures
to
be
then,
treated
these measures
experiments which u l t i m a t e l y are
to
in d i s t r a c t i b i l i t y .
exposition
ability
be
consideration
and
i s based
this
will
which,
introduced
distractibility
set
general
f a c t o r s and
each c l u s t e r
subexperiments. interleaved
w h i c h , on
thesis
individual differences
variables
chapter, and
variables
this
predictors
of
as
separate
constitute will
inform
distractibility
an us and
Predicting
Individual Differences
in
Distractibility 9
Chapter
The A
fundamental
distractibility, its
effect
variables a
task
reasonable
number
choice It
&
of
Jones
be
whether
situations.
Is
Distraction
theoretically question
distractors
the
"Does covary
generalizability
across
for
select
which
distracted
a
with
a
Broadbent,
there
i s a wide
distractibility.
t h a t has
distractibility
created
generalizes
a
across
Generalizable?
primary
to which
focus
will
distraction
to
an
t a s k s and
of t h i s
there
Here, we
within
to t e s t
under
that
that
through
must f i r s t
be
options
cross modality
important.
we
used t o measure
i n t r o d u c t o r y chapter, versus
begin
performance.
i s s u e of the e x t e n t
g e n e r a l i z a b l e i s not
specific
will
is
i t s presence
conditions
of task
and
thesis
can
demonstrated
tasks
modality
the
(1986)
the
of
task
to
i n the
be
of
which can
mentioned
we
individuals
as
Although is
set
very m u l t i p l i c i t y
controversy different
a
of
tasks
is this
reveals
Before
deterioration
Broadbent
this
predict d i s t r a c t i b i l i t y
determine
consequent
Task
of
attention,
behavior.
t h a t may and
Distraction
assumption
like
on
2
distractibility t h e s i s , as
i s some i n t e r e s t
i n t e r a c t i o n s which o n l y attempt auditory
individual?". situations
in may
t o answer
and As
was
visual far
as
i s concerned,
the
Predicting
Individual
Differences
in
Distractibility 10
stance
taken
(1982) and
in
Hunt
for
assumption
and
across
to
a
to
deficit
variety 1983).
disorders
breakdown
to
irrelevant stimuli.
s c r e e n out
this of in
task
processes.
that
attention
may
necessarily variations choice
of
these
subject
many exist
reaction
stimulus
design
best
to
on
seem et
there
to
made t o a
known search.
in On
the
to
some t r i a l s
1979;
abilities here
as
do a
inability
data that
opposes
generalizabi1ity differences
different
attentional
of
of
in
the
et
that
location t h e r e was
i t was
one
al
was
of
are
not
made use
of
t a s k where a an of
no
t h i s area quality
on
attention
letter
so
i n response
the
research
focused
spatial
advance
deficit
how
Broadbent
has
tests,
due
i n d i v i d u a l s best
others.
be
and
is l i t t l e
measures
that
clinical
hyperactivity
viewed
consider
(1986)
classic
to
be
demand
different
similar
in
related
a demonstration
al's
and
us
Eriksen's
filter was
that
A
which
(Douglas & Peters,
can
let
Consider
Broadbent
indicates
In
suggesting
distractibility. the
settings
in focal attention
further,
generalized
where e a c h a t t e n t i o n
distractibility
going
p r e m i s e by
exists
C e r t a i n l y most a t t e n t i o n
non-specific
Sternberg
situations
disabilities,
stimuli
and
of
in intelligence.
learning
different
that
and
attention
generalize,
Before
tasks
i n d i f f e r e n t t a s k s and of
to
i s some d e g r e e o f
different
pertaining
itself
Douglas,
there
generalized
attention
manifests
is similar
individual differences of
literature
thesis
(1980), t h a t
distractibility accounts
this
A or the
need
accompanied
a
B.
target for
by
the
other
Predicting
Individual Differences
in
Distractibility 11
distracting ignore
stimuli,
these.
information
a l s o an
A or a B,
S p a t i a l p o s i t i o n was
and
to r e j e c t
irrelevant
Broadbent e t a l a l s o used the obtain
a
target
measure stimulus
was
not were
conditions
the
was
the a
the
task
digit.
In
was
this
Broadbent
e t a l found
resist
be
or
find
to
subjects
across
attentional
o f the
series little
justify
In
this
known
and
the
variables that
select
filter
evidence
condition
pointing
can
be
the
search
unknown l o c a t i o n
identify
it.
Here
category
and
experiments,
search
f o r any
by
to
consequently
general
ability
Broadbent et a l
i n c o n s i s t e n t p e r f o r m a n c e of
tasks
to
distractor
to d i s t r a c t i o n .
the
to
used. Given these
t a r g e t to
and
of
cue
r e a c t i o n tasks
a t a r g e t a t an
a letter
vulnerable
attempted
tests
to
"categoric nature"
target category
same c h o i c e
location
distractors
the
were t o l d
stimuli.
efficiency.
(digit)
subjects
used a s
of s e a r c h
non-letter
using
but
out
the
manipulated
was
to
(1986)
individual
multitude
w i t h i n and
of
between
of a t t e n t i o n . "If person
we
which
the
than o u t s i d e spot
task
spotlight
at
the
i n the
size
the
spot
amount of
light
of
the
spot,
the
could cast
on
extent
there
and
be
comparable to outside of t h e
differences
contrast
motion
than
factors. in
the
inside rather
t o w h i c h the rather
the
world,
spot,
moved, the
objects
a v a r i e t y of other
could
as
be
i s c o n t r o l l e d from i n t e r n a l
information, task,
a
filtering
people might d i f f e r
with
between
the
of a
directing
different speed
think
the
of
external
In a
search
effect
of
Predicting
Individual Differences in
Distractibility 12
increasing
the
distractors
belonging
the
spatial
target category
and
so
on.
It
area
t o an
attention',
or
irrelevant
of t h e
category,
number
familiar
is
whether
not
obvious
a priori
to a s i n g l e
whether
dimension
they a l l vary
of
of whether
i s a w e l l - e s t a b l i s h e d and
measures a r e a l l r e l a t e d of
of s e a r c h ,
of
one, these
'goodness
independently."
(p.287) This one
to
quote a l o n g conclude
t h a t he
generalize
across
may
been
have
factors
Broadbent
et
results,
and
standard sample
the
differences account two to
task in
f o r the
resolve this of
this
that
be
a
sample s i z e , power
et a l neglected
size
h a r d l y seems c a p a b l e
of c o r r e l a t e d
of d i s t r a c t i o n potential first by
The
section
of
a paper and
inadequate the
will
thesis
pencil
provide
the
twenty f o r each individual
search.
might on
the
In
order
power, one
major
is
to
assess
performance t e s t
individuals. an
the
of a l a r g e
sample s i z e s
and
which
of
performance r e s u l t s
t o a l a r g e group of
procedure
small
for
to s a t i s f y
of d e t e c t i n g
tasks: f i l t e r
p r o b l e m of
of
not
two
which might account
statistical
sample
does
However
d i f f e r e n c e research requirement average
lead
distractibility
abilities.
findings:
and
Broadbent
absence
administered such
specific
distractibility.
distractibility can
different
sensitivity
His
main t y p e s
goal
task
individual
experimental
t h a t h i s measures of
have been o v e r l o o k e d
validity.
size.
believes that d i s t r a c t i b i l i t y
t a s k s or
al's
affect
B r o a d b e n t e t a l ' s r e s u l t s might
assessing
important
will
with
which
I t i s hoped
adequate
test
of
Predicting
Individual
Differences
In D i s t r a c t i b i l i t y 13
individual (Glass
& Hopkins,
The
accepted
noted
the
to
in
confronted
with
performance
of
relatively
validity
select
a
task
is
Irrelevant
to
1975;
distrator
distractors,
of
found
i n discussions
distractors,
Witkin, the
ability
1962). greater or
s i m i l a r i t y i s present "By
relationship
now
The the
confusion
task-distractor
findings:
i s expected
individual
transcends considerations
t o be
inability to
more s i m i l a r
rather
f o r the
in Schiffrin's
hundreds
of
we
such as
(Witkin &
t h e t a s k and
for
than
when
Recall,
dependence
opportunity
the
Hence,
i t i s preferable
confusabi1ity
between s p e e d
between t a r g e t s
task
while
of d i s t r a c t o r s .
of f i e l d
for
d i s t r a c t i b l e when
c l e a r l y d i s t i n c t from t h e t a s k .
physical
difference
highly
presence by
Evidence
This d e f i n i t i o n suggests that
for
positive
are
As
d e f i n e d as
deterioration
individuals
the
Evidence
these
consider the
i n d i s t r a c t i o n , not disembedding a b i l i t y ,
are,
disembedding
we
i s generally
the
who
stimuli.
distractors
Berry,
in
characterized
be
when
stimuli.
containing
by
appropriate
usually
relevant
individuals
selecting
that
power
d e f i n i t i o n of d i s t r a c t i b i l i t y .
found
unaffected
interested
arises
non-distractible
distractibility
are
i n terms o f s t a t i s t i c a l
1, d i s t r a c t i b i l i t y
is
performance
least
operational
distractibility
ignore
of
i n Chapter
inability
at
1984).
question
usually was
differences
measuring
distraction.
b e i n g d e p e n d e n t on (1988) summary o f
studies
testify
to the
o f s e a r c h and t h e s i m i l a r i t y
and d i s t r a c t o r s
and t h i s
of type of t r a i n i n g
relationship
and o t h e r
factors"
Predicting
Individual Differences
in
Distractibility 14
(p.749). press) to
Q u i n l a n and found
that
distractors
other
(cited
search
as
as
in Schiffrin,
of
findings.
in
filter
by
of d i g i t s
evoked,
for
identification
study,
the
important use This
consideration
will
us
targets
parameters.
the
in
which
permit
letters
in
targets each
are
letters
operations
fact,
the
clearly distinct a
more
i n Broadbent et a l ' s
r e s u l t s appeared.
obtain
may
identification
Therefore,
s e l e c t i n g a d i s t r a c t i o n task
are to
In
target
pattern
as d i s t r a c t o r s
involving different cognitive
more h a p h a z a r d
distractors
of
e t a l ' s complex
c a t e g o r i z a t i o n or
d i s t r a c t o r s were t o t h e
the
(1985,
of d i s t r a c t o r s to
and
where t h e
level
p r o c e s s e s t o be
similar
Broadbent
tasks
d i f f e r e n t higher
different
dissimilarity
similarity
explain
search
Duncan
1988).
Thus h i s use
and
( i n p r e s s ) and
i s s p e e d e d by
well
Confounding could
require
Humphreys
from the
an
i s to
targets.
l e s s c o n f o u n d e d measure
of
distractibility. Support
for
distractibility intelligence (1979) is
the as
and
He
mentioned childhood
argues t h a t
attention.
in
attention
dual
task
experiments
earlier, learning
presumes t h a t
i n t e l l i g e n c e across
for
(Keele,
of
in research
on
disabilities. intellectual
function
i n d i v i d u a l s i s p a r a l l e l e d by
differences
s u c h as
although
Neill
well
to
Sternberg
differences
experiments
the
exists
conception
established
abilities this,
of a g e n e r a l i z e d
a major c o n t r i b u t o r
in
support
existence
distractibility.
l i m i t e d , i s found
(Hunt, & De
1980) Lemos,
and 1978).
Experimental
in research
dichotic
using
listening
Predicting
Individual
Differences
in Distractibility 15
Similarly, Deficit the
explain
of
the
time.
Attentional is
sustain
children
manner
(Douglass precise
&
other
situations
and
between
this
selection. assessed, already
tool
Thus
that
is
enough t a s k ,
across the
Learning
disabled
and
used
in
this
thesis
Regardless of the
demonstrate that
i n a manner w h i c h well
as d i s p l a y s
i t is
generalizes consistent
an
i s t o s p e c i f y the d i s t r a c t i o n task
to
task
explain design
appropriate
some
of
e t a l ' s paradigm
f o r measuring
i t
and
the
choosing seen
Broadbent
study
Since
inability
Makings of a D i s t r a c t o r
aim of t h i s s e c t i o n
in
over
t o be d i s t r a c t i b l e i n a
these studies
as
This
generalize
Douglas, 1983).
tasks
attention
in
individuals.
The The
appear
described
1979;
1983).
to
i t appears
hyperactivity
(Sykes, 1973).
hand,
that
Peters,
or
to sustain
appears
t o view d i s t r a c t i b i l i t y
differences
a
also
modalities
to
Disorder
test for
i n a b i l i t y , to
In general
1979; D o u g l a s ,
form of a t t e n t i o n ,
reasonable across
the
impairments.
Attention
frequently
attentional
t o an i n a b i l i t y
attention
on
similar
used
generalized
& Peters,
and a u d i t o r y
on h y p e r a c t i v i t y ,
Disabilities
Deficit
related
(Douglas
visual
some
the causes of these
children
to
research
D i s o r d e r s and L e a r n i n g
existence
that
clinical
the
dictates test
to
what
may have weakened
make
sure
that
for is
is critical.
the problems t h a t
individual differences
important
rationale
its
being
We have
were p r e s e n t i n
i t s u s e f u l n e s s as
in distractibility. we u t i l i z e a s i m p l e
with c l e a r l y i r r e l e v a n t d i s t r a c t o r s , t o assure
that
Predicting
Individual Differences in D i s t r a c t i b i l i t y 16
we
are
measuring
confusion
or h i g h e r
The
are
target
in
(as
isolated
i t
involves
as
in
ability. is
whether
hence e x t r i n s i c
to the be
as when t h e t a r g e t and d i s t r a c t o r s a r e
clear
Figure
that 1A
IB).
Given
extrinsic
our d i s c u s s i o n
distractors
where t h e t a r g e t
isolation
This c o n t r a s t s with
dimensions
Virgi
& Garbart, ).
distractors
(Stroop,
1984, T r e i s m a n ,
Thus we w i l l and c o n c e n t r a t e
extrinsic"
1935;
distractors
avoid
are task
studies
d i s t r a c t o r s and i n t e g r a t e t h e r e l e v a n t
"task
the
1A) or whether t h e t a r g e t must f i r s t
a l . , 1986
called
Taylor,
identifiable,
stimulus
intrinsic"
and n o t d l s e m b e d d i n g ,
consider
identification.
1975; E g e t h , et
to
(as i n F i g u r e
be
intrinsic
Broadbent
been
related
irrelevant
"task
dimension
Figure
simple
use
Berry,
cognitive sorting
clearly
should
preferable,
the
level
and d i s e m b e d d e d
intrinsically
that
distractibility
relevant
distractors
above,
only
with
Witkin &
1982, 1986;
t h e so c a l l e d
on t h o s e
t h a t have
(Davies,
Jones
&
1984). Insert
By
using
an
extrinsic
Figure type
problem
of i n a d v e r t e n t l y measuring
sorting
ability
same
time
order
to avoid
mentioned
other
we r u n t h e r i s k
distractors distractors
or
this
of d i s t r a c t o r , field
of using
are
noticeable Chapter
1.
Messages
At the
d i s t r a c t o r s . In
we d e l i b e r a t e l y s e l e c t e d to
c a n be found
confusion,
dimensions.
ineffective
difficult
we r e s o l v e t h e
dependency,
cognitive s k i l l
s e c o n d a r y problem,
which
in
1
ignore.
What
makes
i n t h e models o f a t t e n t i o n
i n the r e j e c t e d channels are
Figure 1R Task Extrinsic D i s t r a c t o r s Target
Locate the t a r g e t in the following a r r a y :
0 Fiqure IB Task Intrinsic D i s t r a c t o r s Target:
Locate the t a r g e t in the following array:
//
ft
// / ///
Figure (la) R d i s t r a c t o r in which the t a r is distinct from the d i s t r a c t o r items. Figure (lb) Rn embedded figures t e s t in which the target is found in the more complex array. The complex array a c t s as an inteqrated d i s t r a c t o r and task. (From Coren, Porac and Ward, 1984)
Predicting
Individual
Differences
in
Distractibility 17
filtered
out
suggests low
a t an
that
level
e a r l y stage
the
initial
low
these
stimulus
switching
in
divided
presumably
they
perceptual
level
One
physical
factor
attention also
be
on
can
tasks
which
physical
and
characteristic is
is novelty
characteristics
would
process,
s e l e c t i o n i s based
characteristics.
sudden o n s e t , w h i l e a Because
i n the
or
expectancy.
trigger
channel
(Broadbent,
characteristics
1955),
of e f f e c t i v e
distractors. In notion have
his of
to
other
work
unusual
suggestions
of
D.O.
properties
noises,
events.
Hebb
individual.
information
information
time
to
of
low
being
likely that
events
that
selected
sounds as
these d i f f e r e n t t h e o r i s t s orientations) (eg.
do
agree
unexpected, novel,
subexperiment
by
loud
certain
state
of
the
increase
the
physical
frequency
as
to v i s u a l
external
attention.
and
provide
include:
Hebb d i s c u s s
t o c a p t u r e our
theoretical
first
the
opposed
a s a l i e n t stimulus This
i s increased with
we
probability
f r e q u e n c y sound and
most
of
the
high
that
different
dispositions
i n t e r v a l between s t i m u l a t i o n ;
Hence, b o t h Kahneman and
recognize
along
external
stimuli.
to
colors
optimal d i s t r a c t o r s (e.g.
being selected
the
tendencies that
(1955) s i m i l a r l y a r g u e s t h a t
this
of
enduring
what would be
Properties
probability
are
(1973) p o s t u l a t e d
sudden m o t i o n s , b r i g h t
These
information of
intensity;
loud
about
specific
opposed
a t t e n t i o n , Kahneman
"enduring d i s p o s i t i o n s " which are process
noise).
on
It.is
stimuli important
(even w i t h t h e i r on
the
properties
intense).
t e s t s whether d i s t r a c t i b i l i t y
can
Predicting
Individual Differences i n D i s t r a c t i b i l i t y 18
be
assessed
test.
We
behaviorally
must
individuals not has
been
demonstrate
are
distracted
we have a t a s k
in
which
which
there
is
we
can
then
may,
distraction
i n w h i c h some
to a large degree, while
p r e d i c t o r s which can separate
v a r i o u s models
paper and p e n c i l
o r a f f e c t e d t o a much l e s s e r
variability
individuals
a
that
distracted
derived
individual
via
shed
Once a t a s k
a sufficient seek
distractible
later,
extent.
others are
degree of
correlates
and
from n o n - d i s t r a c t i b l e
light
of a t t e n t i o n i n e x p l a i n i n g
on t h e v a l i d i t y o f
distractibility.
Method
The The under
distraction
test
Test
(Appendix
A)
c o n d i t i o n s o f a u d i t o r y and v i s u a l
Specifically, contains items
Distraction
the
distractors
of the s e a r c h
set
of
the
left
test
letters
of
and c r o s s
set
is
a sample
unpredictably
page,
out t h i s
of these
basic search
find
search
around
task
that
the target
i s t o scan
task
the
target
same s e t o f i t e m s
on t h e r i g h t
across a
i t e m which i s
i n the response
s i d e o f t h e page. F i g u r e 2
items.
Insert The
speeded v i s u a l
numbers w h i c h a r e i n g r o u p s o f t h r e e on
the
located
performance
distractor stimulation.
t a s k . The s u b j e c t ' s t a s k
underlined
contains
a
placed
and/or
side
which
is
assesses
Figure
2
i s a variation
of a t e s t
t h a t appears
Figure 2 auu UuA
auu AUU aau UuA
D8R R80
R8D D8R
POC PCO
POC OCP PCC OPC
PBD PDB
DPB BPD PBD DBP
SYX SXY
XYS SXY SYX XYX
PVC PCV
VCP CPV PVC VPC
Figure (2) Sample items from the distraction t e s t without d i s t r a c t o r s present.
8DR RD8
Predicting
Individual Differences in
Distractibility 19
in
the
Differential
1982).
The
clerical
skills.
difficult targets was
original
that
order
This
was
version
used
here
designed
three, rather
i n the
original.
search
mathematical,
and
is
t o measure
slightly
than The
& Wesman,
the
two
more
letter
distraction
test
o n l y minimal c o g n i t i v e
task
relevant stimuli
Seashore
measured
not
verbal
their or
individuals' competency f o r
some o t h e r
higher
skill.
auditory
which
will
one be
Auditory
timed
stimuli
modality.
distractors,
and
placed
contains
a
with
subject
visual
and
in either
had
one
one
with
a
sections.
duration the
of
task
visual
distractors
of
c o m p r i s e an
items.
extrinsic
include
distractors
task
In t h e
were
visual
meaningful
t a r g e t items.
Figure
T h e s e d i s t r a c t o r s and
type
of
test.
was
3
the
Examples of
the
p i c t u r e s of a s k e l e t o n , a s k i e r ,
a
s e c t i o n , while
the
visual
search
task
meaningful auditory d i s t r a c t o r s ,
ranging
f r o m 75
were
were
presented
periods
of
In t h e
without
Control, Visual
minutes.
the
or
auditory distraction
subjects
boat.
these
the
distractors
u n p r e d i c t a b l y around
sample
section
Each s e c t i o n of the three
visual
the v i s u a l
auditory
r e f e r r e d t o r e s p e c t i v e l y as
search
a
Each
section
pictures
and
were p r e s e n t e d
Distraction had
distraction
dog
test
simple
memory,
Irrelevant
and
(Bennett,
t o r e q u i r e c o n c e n t r a t i o n but
to s e l e c t
prolonged
Test
aptitude
i t contains
were f o u n d
engagement. ability
The
because
designed
Aptitude
performing
at v a r i a b l e , unexpected
silence
averaged
three
eighteen
t o 95 d e c i b e l s ,
intervals.
Interspersed
s e c o n d s . Examples of
these
Predicting
Individual
Differences
in Distractibility 20
distractors
include
sounds of a screaming s i r e n ,
a dog b a r k i n g and a u d i e n c e
was
which
noted
no
on
Figure
were
the
no
sections
The section
provided
condition
in
comparison
of
compared
with
a measure o f t h e
of the d i s t r a c t o r s .
In
addition
there
was
three
sections
included
to
the
task are
in
context
and
test
the
auditory
being a c t i v e l y
group d e s c r i b e d group r e c e i v e d
fatigue,
or p r a c t i c e
not
considered
I t was
effects.
and t h e i r r e l e v a n t to
of t h i s study,
stimuli
above,
t h e same
w i t h no d i s t r a c t o r s .
i s a search task
numbers
Distractors, pictorial
g r o u p . The c o n t r o l
f o r any o r d e r ,
that
and
experimental
of the search
to test
letters
the
a control
Notice
stimuli
a control
present.
distractor
p e r f o r m a n c e on t h e d i s t r a c t o r effects
3
above t h e r e was a l s o
distractors
performance
baby,
noise.
Insert As
a crying
irrelevant
be
distractors.
refer to
only to the
t h e domain o f
categorized. Subjects
Three University 272 group test
of
subjects
which
visual
reversed.
and
British
eight
of
appears of and
73
undergraduate
subjects
Columbia served as s u b j e c t s .
participated
consisted
consisting the
hundred
199
i n two e x p e r i m e n t a l
subjects auditory
A second
who r e c e i v e d distraction
Of t h e s e ,
g r o u p s . The
s u b j e c t s who r e c e i v e d
i n A p p e n d i x A.
a t the
the d i s t r a c t i o n
experimental
t h e same t e s t sections
first
of
group
but with the
test
20a
CTi . - s i i r - . . — .
O
nvx xvn vxn nxv xnv
nvx nxv _3S„xnv vxn xvn
bid dlb ldb lbd bdl
dlbl
aru aur ura rau rua
ura aru^^Sr aur rua rau
vwu
wvu
uwm
wum
i
uvw vwv vuw
....
Ldb
bid bdl lbd
vuw wvu uwv vwu
uvw
0wu
umw
wmu umw vum^j^mwu uwm
679 769 967 697
976
697 967 769 679 976
wmu
Figure (3) Sample items from the distraction t e s t with d i s t r a c t o r s present.
Predicting
Individual Differences in D i s t r a c t i b i l i t y 21
The
size
of
these
groups should
for
meaningful c o r r e l a t i o n a l
and
should A
test
have a d e q u a t e
smaller for
this
but
no
merely This
group.
Only
three
smaller
individual
allow
power.
c o n t r o l c o n d i t i o n o f 36 s u b j e c t s was
task.
because
l a r g e enough t o
a n a l y s i s of i n d i v i d u a l d i f f e r e n c e s ,
f a t i g u e or p r a c t i c e e f f e c t s .
distractors, search
be
T h i s group, r e c e i v e d
successive group
included to
presentations
size
of the
i s p e r m i s s i b l e here
d i f f e r e n c e a n a l y s i s i s t o be p e r f o r m e d the group
no
performance, w i l l
be a s s e s s e d
on in
this condition.
Results
Group The
basic
distraction a
number
task of
not
as
in
individual
of idea
that
Individuals
The
Table
1
variability
individual scores
be
us w i t h who
answered
here,
are d i s t r a c t e d
to their
in the
wide
the
i n performance
distractors
distractor
are
relatively
o f t h e number c o r r e c t
existence
of
but not o t h e r s ,
hence
sufficient
on t h e d i s t r a c t i o n
conditions are
containing
no
d i f f e r e n c e a n a l y s i s m e a n i n g f u l . The the d i s t r a c t o r
the
(show p e r f o r m a n c e
performance with
distribution
illustrates
i s whether
a range o f s c o r e s ,
w e l l as a number o f i n d i v i d u a l s who
distracted.
scores
make
provides
relative
Performance
to
individuals
deterioration stimuli)
question
& Discussion
task
wider
range
i s c o n s i s t e n t with
having spreading
an
effect
the s c o r e s
to
the
upon some out.
Predicting
Individual Differences in
Distractibility 22
Insert In o r d e r we
will
to assess
focus
decrease
on
accuracy
distractors.
T h i s was
mean
of
condition p