Series Advances in Experimental Medicine and Biology, Volume 438, 1998 Plenum Press, 1027-1032
| ' | |
| CORRELATION BETWEEN PUPIL DIAMETER AND VISUALLY INDUCED DISCOMFORT | |
| Tạp chí Series Advances in Experimental Medicine and Biology 2002 1998; 438 ():1027-1032 | |
| Tác giả | Vo Van Toi *, D. S. Landmann |
| Nơi thực hiện | Department of Biomedical Engineering, Bioengineering Center,Tufts University, 4 Colby Street, Medford, MA 02155 |
| Từ khóa | CORRELATION,PUPIL |
| DOI URL [ PDF] | |
English[sửa]
Purpose: This investigation explores whether discomfort induced by visual stimulation causes a variation in pupil diameter. This can be used as an objective index of discomfort in virtual reality studies and clinical investigations.
Methods:
Three
male
and
three
female
observers,
naïve
to
the
study,
average
age
26±12.7
years
old,
participated
in
the
study.
Visual
stimulation
was
induced
by
an
optokinetic
drum,
which
consists
of
alternating
black
and
white
stripes
(14°
arc)
that
rotated
past
the
subject
at
10
rpm.
Illuminance
was
150
lux
and
remained
constant
throughout
the
experiment.
Observers
wore
a
head-mounted
eye-tracking
device
(I-SCAN)
which
measured
pupil
diameter
at
60Hz.
Before
the
experiments,
subjectivity
to
motion
sickness
of
the
observers
was
evaluated
using
a
standard
questionnaire1.
During
the
experiment,
every
30
seconds,
observers
recorded
their
subjective
level
of
discomfort
(from
1
to
4)
using
a
handheld
microprocessor
controlled
data
acquisition
device
that
we
developed.
At
the
end
of
the
experiment,
overall
observer's
discomfort
felt
throughout
the
study
was
evaluated
using
a
standard
Simulator
Sickness
Questionnaire2
(SSQ).
Two
sets
of
experiments
were
administered.
First,
to
establish
a
baseline
pupil
diameter,
observer's
pupil
diameter
was
recorded
for
8
min
without
visual
stimulation.
Second,
the
experiment
to
induce
visual
discomfort
with
the
rotating
drum
was
performed
for
a
maximum
of
25
min
or
until
observers
requested
termination;
during
that
time
the
pupil
diameter
and
the
subjective
level
of
discomfort
were
measured.
Results:
Two
observers
were
placed
in
each
of
three
tiers
of
discomfort
based
on
the
SSQ:
“mild”,
“moderate”
or
“severe”.
Upon
initiation
of
drum
rotation,
pupil
dilation
was
noticed
in
all
observers
(p=0.008),
and
was
most
remarkable
in
the
“severe”
group.
Pupil
diameter
dilated
by
an
average
of
18%
in
the
“severe”
group
and
only
7%
in
the
“mild”
group.
Conclusion:
Changes
in
mean
pupil
diameter
in
response
to
vection
is
measurable
and
statistically
significant.
There
is
a
strong
correlation
between
the
susceptibility
scores,
the
percent
increases
in
mean
pupil
diameter
and
the
symptoms
of
discomfort.
These
results
suggest
that
the
pupil
diameter
can
be
used
as
an
objective
index
to
assess
levels
of
visually
induced
discomfort.
