Figure 1,

hand was located in the position specified at all
times. A final physiological measure (oral tem-
perature) was obtained from a standard clinical
thermometer. All recording and programing
apparatus were located in a separate room from
which the S was visible through a one-way
mirror.

C. Procedure. On arrival, the S was taken
to the testing room, given orientation instruc-
tions, and then instrumented for physiological
recording. Following this, the S was adminis-
tered a subjective rating scale dealing with his
present feelings, attitudes, and emotions. The
S was asked to rate, on a nine-point scale, his

A typical stimulus pattern as displayed to the subject.

levels of attentiveness, fatigue, strain, boredom,
and irritation. The items on the rating scale
closely approximated those used by Barmack.®

The task instructions were then given to the
S. It was emphasized that the S was to attend
to the simulated radar display at all times and
to respond as rapidly as possible to any critical
stimulus as soon as one was detected. Following
completion of the task instructions, three blood
pressure recordings were obtained and oral tem-
perature was measured. Precautions were taken
to insure that the S did not eat, consume any
liquids, or smoke for 30 minutes prior to the
time his temperature was measured.



with some conceiving of boredom and monotony
as states of diminished arousal?! ?? and others, as
states of heightened arousal.*® There was little
evidence in the present study to support either
view. Rather, the nature of the changes in those
physiological, performance, and subjective’ vari-
ables that differed significantly between the ex-
treme groups suggests that the principal pattern
characterizing boredom and monotony was more
closely related to attentional processes than to
“arousal.”

Protracted exposure to the task used, as was
the case with Barmack’s® studies, might have
resulted in significant relationships between
reported boredom-monotony and some of the
rather traditional physiological and subjective
arousal indices employed here. However, the
results of the present study imply that declining
(or increasing) “arousal” is not a necessary cause
of feelings of boredom and monotony.

There were no differences between the High
and Low Boredom-Monotony Groups on either
the Extraversion scale of the Eysenck Personal-
ity Inventory or the General Sensation Seeking
and Boredom Susceptibility scales of the Zucker-
man Sensation Seeking Scale. The lack of any
relationship with extraversion was somewhat
surprising, since several previous studies have
shown this variable to be related to perform-
ance decrement on vigilance and _ repetitive
tasks.‘ #9791628 Although the Zuckerman scales
apparently have not been used in studies of com-
plex vigilance, Zuckerman concedes that his
scales, originally developed as possible predictors
of response to sensory deprivation, have been
poorest in this area of prediction.*° Boredom
susceptibility is commonly felt to be an important
factor in the inability to tolerate sensory depri-
vation.

It may be that the task employed in the pres-
ent study was sufficiently novel and the length
of exposure too short to allow extreme feelings
of boredom and monotony to develop. Had Ss
been exposed to the task over several adaptation

periods, significant relationships with the Ey-
senck and Zuckerman scales might have been ob-
tained. Future research using a computer-
generated display will allow the use of extended
adaptation periods and enable a more thorough
investigation of possible relationships between
personality variables and self-rated boredom and
monotony.

V. Conclusions.

The results of this study clearly indicate a
relationship between self-rated boredom-monot-
ony and monitoring performance. Subjects who
viewed the task as highly boring and monotonous
showed a significant increase in their longest
response times to the critical stimuli, while Ss
who viewed the task as interesting and not mo-
notonous showed a decrease in all measures of
response time. The greater increase in heart-rate
variability and decrease in rated attentiveness
among the high boredom-monotony Ss suggests
that these Ss were unable or unwilling to main-
tain a uniform level of task attention. The
mean longest response time among the high
boredom-monotony Ss was approximately 6 sec-
onds. While this value is not that impressive in
itself, the task duration was relatively short,
target density was not excessively high, and the
S was always aware that no stimulus could
change until the next filmstrip was presented.
It is quite likely that differences between high
and low boredom-monotony Ss in response times
to critical events would be more pronounced with
a longer task duration, higher target densities,
and fewer cues as to when critical changes might
occur. Future research using a computer-
generated radar display will incorporate some
of these changes and enable a more comprehen-
sive appraisal of the importance of individual
differences in perceived boredom-monotony and
monitoring performance. Further investigation
of psychometric instruments that might predict
boredom susceptibility is also planned.


All the variables showing significant changes
from the first to the second measurement period
declined in value except body movement, which
showed an increased level of activity. The only
variable that differed significantly (p<.05) as
a function of time of day was oral temperature.
As shown in Table 2, temperature was higher in
the late afternoon than in the morning, with a
dip occurring during the early afternoon period.
The one significant (p<.05) interaction was the
periods-by-time-of-day effect for diastolic blood
pressure. Table 2 shows that diastolic blood
pressure decreased during the measurement pe-
riods for the first two time-of-day groups and
increased for the last group. The meaning of
this particular pattern is unclear.

The rating scale data are given in Table 3.
Analyses of variance applied to each of the

TABLE 3, Mean Values Obtained for Each Rating Scale

Variable for the Three Time-of-Day Groups

Measurement Period

Variable Group Prior to Task End of Task
1000 7.80 4,33
BoredonTM 1300 7:93 4193
1530 7293 5107
a 1000 8.67 7,53
Teritacion 1300 8193 8140
1530 9100 793
a 000 3.60 5,00
Attent iveness 1300 3:20 5200
1530 2167 5127
> 1000 4,00 5.87
Fatigue 1300 4133 6.20
1530 447 3
a 1000 5.93 4,93
Strain 1300 6.07 an
1530 5167 5180
1000 one 3.60
Nonotony* 1300 307

1530

4 Lower numerical values indicate higher levels of the variable.

> Wigher numerical values indicate higher levels of the variable,

variables (except monotony) revealed that the
changes from the first: to the second measure-
ment period were significant in every case.
(p<.05). The direction of the changes indicated
an increase in boredom, irritation, fatigue, and
strain from the beginning to the end of the task
along with a decrease in attentiveness. There
were no significant differences between the time-
of-day groups and no significant interactions. A
simple analysis of variance of the monotony data

revealed no significant difference (p>.05) be-
tween groups.

B. Comparison of High and Low Boredom-
Monotony Groups. The boredom and monotony
scores obtained from the rating scale adminis-
tered at the completion of the task period were
summed together for each S. From the resulting
distribution, eight Ss with the highest scores and
eight with the lowest were selected to form the
High and Low Boredom-Monotony Groups.
(These groups will henceforth be referred to as
the High and Low Groups.) Both groups had
identical mean ratings on the boredom scale
prior to the beginning of the task. Mean ratings
for boredom and monotony at the completion of
the task were 2.0 and 1.2 for the High Group
and 7.4 and 6.8 for the Low Group. The state-
ments on these scales corresponding to the above
numerical values revealed that the High Group
experienced moderate to extreme boredom toward
the end of the task period and felt the task itself
to be extremely monotonous, while the Low
Group experienced greater-than-moderate inter-
est in performing the task and did not perceive
it to be monotonous.

While not specifically equated for time of day
tested, both the High and Low Groups were
approximately equivalent with respect to this
variable. Of the High Group, three Ss were
tested at 1000, three at 1300, and two at 1530;
of the Low Group, three were tested at 1000,
two at 1300, and three at 1530.

Mean physiological, performance, and rating
scale values for the High and Low Groups are
shown in Tables 4, 5, and 6 respectively. Since
the two subgroups were formed from the larger
group of 45 Ss, one would expect the between-
periods changes for each variable that were sig-
nificant in Tables 1, 2, and 8 to be significant
for the data shown in Tables 4, 5, and 6 as well.
Analyses of variance applied to the physiological
data given in Table 4 revealed this to be the case
for all variables except diastolic blood pressure,
which showed a significant decline from the be-
ginning to the end of the task period in the
larger group but not in the subgroups. There
were no significant between-group or interaction
effects for any of the variables with the excep-
tion of a significant (p<.05) interaction effect
for heart-rate variability. As Table 4 shows,
heart-rate variability from the first to the second



After the 1-hour task period, blood pressure
and oral temperature were again taken, and the
S completed a second form of the subjective
rating scale. This form was like the first, except
that the S was asked to rate each of the items
with respect. to how he felt near the end of the
task he had just completed and an item was
added in which the S rated how monotonous he
felt the task to be toward the end of the task
period. After the S completed the rating scale,
the electrodes and blood pressure cuff were re-
moved, and the S was asked to complete Form A
of the Eysenck Personality Inventory” and the
Zuckerman Sensation Seeking Scale.

D. Measurement of the Performance and
Physiological Data. The performance data were
computer processed and the following measures
were obtained for each of the 30-minute periods:

© Mean response latency to the critical stimuli.
© Standard deviation of response latencies.
© Number of critical stimuli missed.

The computer program described in a previous
report” was used to obtain the mean and stand-
ard deviation of heart rate for each successive
5-minute period. These were then averaged to
give values for the two 30-minute periods. A
separate computer program summed the number
of pulses from the body movement integrator
for each 30-minute period. Conductance was
measured during the first, middle, and last 5
minutes of the task period and averages were
computed for the first and second half hours.
In measuring the three blood pressure recordings
taken at the beginning and end of the task
period, the systolic pressure was determined by
the appearance of the first Korotkoff sound as
recorded on the Dynograph. Diastolic pressure
was taken to be the first Korotkoff sound having
an amplitude less than one-third the amplitude
of the maximum recorded sound. This tech-
nique has been used by Cartwright‘? and cor-
relates well with conventional clinical measure-
ments. The three systolic and diastolic measures
were averaged separately for the beginning and
end of the task. Oral temperature was read to
the nearest tenth of a degree.

III. Results.

A. Time-of-Day Effects. Performance data
for the three time-of-day groups are shown in

Table 1. Analyses of variance revealed no sig-
nificant (p>.05) group, measurement period, or
interaction effects for either mean latency or
variability of response latencies to the critical
task stimuli. Since none of the critical stimuli
was missed by any of the Ss, this measure is not
included in the table.

TABLE 1, Mean Values Obtained for Each Performance

a
Variable for the Three Time-of-Day Groups

30-Minute Periods

Variable Group 1 2

1000 2,82 2.73
Latency to 1300 2265, 2.76
Critical Stimli (sec) 1530 3,02 2.86

1000 0.78 0.97
8D of Latencies to 1300 0.84 0.93,
Critical Stimuli (sec) 1530 0.76 0.91

® Since no $ missed any of the critical stimli, errors of omission
fare not included in the table.

Table 2 gives the physiological values obtained
for the three groups. Analyses of variance
yielded significant F values (p<.01) for periods
for all variables except heart-rate variability.

TABLE 2, Mean Values Obtained for Each Physiological

Variable for the Three Time-of-Day Groups

Measurement Period

Variable Group 1 2
Conductance 1000 9.35 8.54
@ mhos)* 1300 12.30 preys
1530 illa2 11.02
Oral Temperagure 1000 98.22 97.99
(degrees F.)' 1300 98.05 97.87
1530 98.62 98.19
Systolic BP 1000 126.66 117.62
(nn Hg)! 1300 119.71 112175
1530 117.86 112.6
Diastolge BP 1000 75.37 72.75
(om He)! 1300 76.00 68.93,
1500 72.33 72.71
Heart,Rate 1000 83,27 80.27
(opm) 1300 73.87 72.58
1500 79.58 76.43
Heart,Rate SD 1000 7.19 7,19
(opm)* 1300 6.89 7.25
1500 7M 6.97
Body Movement a 1000 165.00 263.60
(integrator pulses)’ 1300 118.13 223.00
1530 131,40 205.87

* values shown are for the first and second half hours of the task
period.

> :
Values shown afe for the beginning and end of the task period.


TABLE 6, Mean Values Obtained for Each Rating Scale Variable

for the High and Low Boredom-Monotony Groups

Measurement Period

Variable Group Prior to Task End of Task
a

Irritation Low 9.0 8.2
High 9.0 6.4

Attentiveness® Low 3.6 44
High 27 6.0

>’

Fatigue Low 4h 5.7
High 3.4 6.5

Strain® Low 64 5.9
High 6.4 3.5

* Lower numerical values indicate higher levels of the variable.

> Higher numerical values indicate higher levels of the variable.

on the Extraversion scale of the Eysenck Per-
sonality Inventory and on the General Sensation
Seeking and Boredom Susceptibility scales of the
Zuckerman Sensation Seeking Scale. Scores on
the Mean Extraversion, General Sensation Seek-
ing, and Boredom Susceptibility scales were
12.4, 14.9, and 9.6 for the High Group and 12.6,
12.6, and 7.6 for the Low Group. While the
High Group had larger mean values than did
the Low Group on both of the Zuckerman scales,
t-tests revealed that none of the differences be-
tween groups on any of the scales was significant
(p>.05).

IV. Discussion.

With the possible exception of oral tempera-
ture, there was no evidence of any “postlunch
dip” in physiological activity, performance, or
subjective response. Thus, the suggestion of
greater boredom and poorer performance among
Ss in the early afternoon group of the pilot
study was not supported by the present data.

For all three time-of-day groups, the physio-
logical and subjective changes from the begin-
ning (or first half hour) to the end (or second
half hour) of the task period were generally in
accord with the results of previous studies of
such changes during performance of monotonous
tasks? £62718 2526 2728 The general pattern was
one of a decline in conductance, oral tempera-
ture, blood pressure, heart rate, and attentiveness
along with an increase in general body move-
ment, boredom, irritation, fatigue, and strain.
Neither heart-rate variability nor task perform-
ance showed any change during the test session.

This latter finding is interesting, since a previous
study of repetitive, monotonous performance
revealed that increases in response variability
(taken as an index of declining attention) were
accompanied by increase in heart-rate variabil-
ity.® From the lack of change in heart-rate
variability and task performance in the present
study, it could be inferred that attention to the
radar task showed little evidence of decline, even
though the task was generally rated as somewhat
boring and moderately monotonous. It should
be noted, however, that although rated attentive-
ness declined from the beginning to the end of
the task, the change was from a mean initial
rating of “quite attentive” to a final rating of
“attentive.”

It is obvious that the pattern of physiological,
performance, and subjective changes that oc-
curred cannot be taken as uniquely representa-
tive of a monotony-boredom pattern; to do so
would require comparing the pattern to that
obtained on a task clearly rated as interesting
to most Ss. Difficulties with this approach be-
came evident during the initial pilot study.*
The alternative approach used in the present
study was to compare patterns of Ss falling at
the extremes of rated boredom and monotony.
For the physiological and performance measures,
significant differences between the groups were
found for heart-rate variability and for mean
and variability of latency to the critical task
stimuli. The High Boredom-Monotony Group
increased in these measures from: the first to the
second half of the session, while the Low Group
decreased. The performance decrement shown
by the High Group was found to be directly
attributable to this group’s increase in their
longest. response latencies. An increase in the
frequency or duration of “long response times”
in vigilance or repetitive tasks has been hypothe-
sized to be a reflection of declining attention.°
Likewise, increased heart-rate variability has
been linked in a variety of studies to indices of
lowered or fluctuating attention.'® * °° Of the
two subjective measures significantly differen-
tiating between the groups, one of these was
attentiveness, with the High Group showing the
greater decline. The High Group also experi-
enced greater strain during the task period, pos-
sibly as a reaction to declining attention.

Theorists of boredom and monotony have
tended to focus on “arousal” interpretations,



Technical Report Documentation Page

T. Report No. 2. Government Accession No. 3. Recipient's Catalog No.

FAA-AM-75-8

4. Title and Subtitle

PHYSIOLOGICAL, SUBJECTIVE, AND PERFORMANCE CORRELATES
OF REPORTED BOREDOM AND MONOTONY WHILE PERFORMING A
SIMULATED RADAR CONTROL TASK

3. Report Dote

&. Performing Organization Code

L.
8. Performing Organization Report No.

7 Authors) Richard I. Thackray, Ph.D., J. Powell

Bailey, M.S., and R. Mark Touchstone, M.S.

9. Performing Organization Name and Address . Work Unit No. (TRAIS)
FAA Civil Aeromedical Institute
P.O. Box 25082

Oklahoma City, Oklahoma 73125

7 Contract of Grant No.

|. Type of Report and Period Covered

12. Sponsoring Agency Nome and Address
Office of Aviation Medicine
Federal Aviation Administration
800 Independence Avenue, S.W.
Washington, D.C. 20591

OAM Report

|. Sponsoring Agency Code

15. Supplementary Notes

This research was conducted under Task AM-C-75-PSY-48.

16, Abstract

Forty-five male subjects performed a simulated air traffic control radar task for
1 hour. Subjects were equally divided into three time-of-day groups and tested at
1000, 1300, and 1530, The subject's task was to respond as rapidly as possible to
infrequent changes in alphanumeric symbols, Physiological recordings of blood
pressure, oral temperature, skin conductance, body movement, heart rate and heart-
rate variability, and performance measures of mean response latency and variability
of response latencies were obtained. In addition, subjects rated their levels of
boredom, monotony, irritation, attentiveness, fatigue, and strain at the beginning
and end of the session. There were no differences between any of the time-of-day
groups except in oral temperature, which was significantly higher in the afternoon
than in the morning. Two extreme groups of eight subjects each were formed on the
basis of their rated boredom and monotony and compared with respect to changes in
each of the measures during the task period. The two groups differed significantly
on several measures, with the high boredom-monotony group showing greater increases
in "long response times," heart-rate variability, and strain along with a greater
decrease in attentiveness. The nature of the pattern associated with boredom and
monotony suggests a pattern more closely related to attentional processes than to
"arousal." The extreme groups did not differ on the Eysenck Extraversion Scale

or the Zuckerman General Sensation Seeking and Boredom Susceptibility Scales.
Possible reasons for the lack of relationship with these scales are discussed.

17. Key Words T8. Distribution Statement

Air Traffic Control Heart-Rate [Document is available to the public through
Arousal Variability the National Technical Information Service,
Automation Performance Springfield, Virginia 22151

Boredom Vigilance

19. Security Classif. (of this report)

Unclassified

0. Security Classif. (of this page)

Unclassified

DV. No, of Pages | 22. Price

$9.99 FE

Form DOT F 1700.7 (8-72)

Reproduction of completed page authorized





n

2

2

10.

11,

18.

14.

15.

16.

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TABLE 4. Mean Values Obtained for Each Physiological

Variable for the High and Low Boredom-Monotony Groups

Measurement Period

Variable Group 1 2
Conductagee Low 9.12 8.62
Gi mhos)® High 12.36 11.66
Oral Temperagure Low 98.17 98.02
(degrees F.) High 98.30 97.81
Systolig BP Low 123.74 117,50
(om He) High 122.54 116.00
Diastolic BP Low 79.83 mn
(rm Hg) High 74.83 7.75
Heart Rate Low 80.78 76.79
(bpm) ® High 7241 71.55
Heart Rate SD Low 8.35 7.09
(bpm) High 7.78 8.62
Body Movement a Low 92,50 160,50
(integrator pulses) High 172,20 303.40

* valves shown are for the First and second half hours of the task
period.

* values shown are for the beginning and end of the task period.

half of the task period decreased for the Low
Group and increased for the High Group.

With regard to the performance data in Table
a significant (p<.05) difference was found

ad

---- Low Group
—— High Group

9
°
(oe

% Longest Response Latency (Secs.)
2
a

Ist 1/2 Hr. 2nd 1/2 Hr.

Ist 172 Hr. 2nd 1/2 Hr.

% Shortest Response Lotency (Secs,)

Measurement Periods

Fiaure 2. Mean shortest and longest latencies for the
high and low boredom-monotony groups.

between the two groups in mean latency to the
critical stimuli, with the High Group having
longer response times than the Low Group. For
both mean latency and latency variability, there
were significant (p<.05) group-by-period inter-
actions. The meaning of these significant effects
is clarified in Figure 2. This figure plots the

TABLE 5. Nean Values Obtained for Each Performance

Variable for the High and Low BoredomMonotony Groups

Measurement Period

Variable Group 1 2

Latency to Critical Low 2.85 2.27
Stimuli (sec) High 3.10 3.26
SD of Latencies to Low 0.87 0.70
Critical Stimili (sec) High 0.82 1.31

mean values of the single shortest and longest
latencies for Ss in each group in the two half-
hour periods. Analyses of variance conducted
on these data revealed a significant (p<.05)
decline in shortest latencies during the first and
second half hours for both groups, but no sig-
nificant between-group or interaction effect. For
the longest latencies, the only significant effect
was the interaction effect (p<.05). As Figure 2
reveals, the significant interaction effects for
mean latency and latency variability shown in
Table 5 can be attributed to an increase in the
magnitude of “long response times” to the criti-
cal stimuli by the High Group and a decrease
by the Low Group.

Rating scale data for both groups are shown
in Table 6. Analyses of variance revealed sig-
nificant differences (p<.01) between the two
measurement periods for all variables. While
the High Group appeared to show greater
changes from the beginning to the end of the
task period than did the Low Group, the inter-
action effects were significant (p<.05) for only
two of the rating variables. These were atten-
tiveness and strain, with the High Group show-
ing a greater decrease in attentiveness and a
greater increase in strain. There was also a
significant difference between groups (p<.05)
on strain, but as Table 6 clearly reveals, this was
simply a reflection of the significant interaction
effect.

A final aspect of the data analysis was a com-
parison of the two groups with respect to scores


tionships between boredom-monotony and_per-
formance. Consequently, Ss in the present study
were tested during morning and afternoon ses-
sions in an attempt to determine whether a time-
of-day effect had to be considered in interpreting
the obtained results.

II. Method.

A. Subjects. Forty-five paid male college
students were randomly assigned to three groups
of equal size. The groups differed only in the
time of day tested: 1000, 1300, or 1530. All
Ss were right handed and had no prior experi-
ence with the task used.

B. Apparatus and Task Design. A Grafiex
Model 750 film-strip projector was used to
project stimuli onto the rear of a 40-centimeter
(diameter) Polacoat screen. The screen itself
was located in a console designed to resemble an
air traffic control radar unit. The stimuli dis-
played consisted of targets, or “blips,” represent-
ing aircraft flying along specific routes at various
speeds. Adjacent to cach target was an alpha-
numeric symbol consisting of two letters, three
numbers, and a final letter. The first two letters
identified the aircraft and the three numbers
indicated its altitude. For example, SA150
might represent Standard Airlines flying at
15,000 feet. The final letter-—“C” or “N”—indi-
cated the altitude’ status of the aircraft; “C”
signified that the aircraft was maintaining its
assigned altitude, while “N” indicated that the
aircraft had departed from its assigned altitude.
The occurrence of “N” constituted a critical
event, and the S was instructed to press a button
on the right panel of the console whenever he
detected that such an event had occurred. There
were 10 critical stimuli (“N”) in the two suc-
cessive 30-minute periods of the task. No more
than one critical stimulus was ever present on
any given frame of the filmstrip, and each criti-
cal stimulus reverted to “C” on the next frame.
The mean interval between critical stimuli was
3 minutes.

The S was exposed to each filmstrip frame for
15 seconds. With each successive frame of the
filmstrip. the targets advanced at simulated air-
speeds of either 300 or 600 knots. These two
speeds were equally distributed among the tar-
gets displayed. The number of targets on any
given frame ranged from 6 to 10 with a mean of

8. Targets were distributed across all quadrants
of the screen to keep scanning requirements ap-
proximately constant. Film advance was auto-
matically controlled by timers, and a shutter
mechanism blanked out the screen between
frames. The total task was similar to one em-
ployed by Adams, Stenson, and Humes.'' Figure
1 shows a typical stimulus pattern as displayed
to the S.

Response times to the critical stimuli were
measured in hundredths of a second by means
of a Welford Mark V Serial Event Timer and
Recorder (SETAR) with a paper tape output.
On each frame of the filmstrip containing a
critical stimulus was a small transparent circle
near one of the outer edges that allowed light
from the projector to fall on a photocell. The
output of the photocell activated one of the in-
puts to the SETAR, which measured elapsed
time from frame exposure (stimulus onset) until
S’s response. If the elapsed time exceeded 14
seconds, the event was recorded as an error of
omission.

A Beckman Type R Dynograph was used in
recording skin conductance, heart rate, body
movement, and blood pressure. Heart rate was
obtained from Beckman biopotential electrodes
attached to the lateral walls of the S’s chest;
leads from the electrodes were connected to a
cardiotachometer coupler. Biopotential elec-
trodes filled with a saline paste’* were attached
to the volar surfaces of the index and middle
fingers of the S’s left hand. Leads from these
electrodes led to a Beckman Type 9844 coupler
that measured conductance directly, An arm
cuff was used in conjunction with an E&M In-
strument Company electrosphygmograph to ob-
tain recordings of blood pressure. Gross body
movement was obtained from a crystal finger-
pulse transducer attached to a cushion on the
S’s chair. The output of this transducer was
amplified and then integrated (by using a pulse
integrator), and the pulses were recorded on the
Dynograph. Outputs from the cardiotachometer
and the pulse integrator also Jed to the SETAR
for subsequent computer analysis of heart rate,
heart-rate variability, and frequency of body
movement. In addition, one channel of the
Dynograph recorded the output of a photocell
recessed in the shelf of the S’s console. The
purpose of the photocell was to enable the ex-
perimenter to visually insure that the S’s right


PHYSIOLOGICAL, SUBJECTIVE, AND PERFORMANCE CORRELATES
OF REPORTED BOREDOM AND MONOTONY WHILE PERFORMING
A SIMULATED RADAR CONTROL TASK

I. Introduction.

There is an increasing trend toward automa-
tion of air traffic control systems. While present
systems can best be described as semiautomated
and still leave the controller with a considerable
amount to do, projected trends in the develop-
ment of fully automated systems suggest the
distinct possibility that the future role of the
controller may be far more that of a system
monitor than that of an active participant in
traffic control. Indeed, Barnes and Dickson’
have stated that in the future, the controller may
well “manage by exception in that his direct in-
volvement would only be required when certain
system limits were exceeded or in case of mal-
function (p. 26).”

Fully automated air traffic control systems
may be technologically feasible and even ad-
vantageous from a cost-effectiveness standpoint.
However, it seems likely that present-day con-
trollers would find the job of passively monitor-
ing a virtually autonomous system to be mo-
notonous, boring, and unsatisfying. Because of
this, certain tradeoffs will ultimately be neces-
sary to achieve man-machine configurations that
will minimize the undesirable aspects and maxi-
mize efficiency. But, in attempting to make
intelligent decisions regarding tradeoffs, we need
considerably more information to determine the
degree to which, and the manner in which, feel-
ings of boredom and monotony influence per-
formance efficiency in complex vigilance tasks.

There has been virtually no laboratory research
relating boredom and monotony to performance
since the classic work of Barmack in 1937.5
Barmack found that in the performance of a
pursuit rotor task as well as in the performance
of a repetitive addition task, those individuals
who experienced the greatest increase in boredom
generally showed increased errors and decreased

work output. Boredom was also associated with
increased fatigue and irritation along with de-
creases in attentiveness, oxygen consumption,
blood pressure, and, to a lesser extent, heart rate.
While this overall pattern of subjective, physio-
logical, and performance changes tended to be
associated with boredom in many subjects (S),
there were fairly numerous exceptions, and Bar-
mack did little to quantify the degree of inter-
relationship between these changes.

The present study is essentially an extension
of Barmack’s early work with the addition of a
complex visual monitoring task patterned after
contemporary air traffic control radar displays.
The primary purpose was to examine in detail
the physiological, subjective, and performance
changes accompanying reported boredom and
monotony during performance of this task.

In a pilot study conducted to investigate
various characteristics of the monitoring task,
two separate groups of eight Ss with no prior
experience on the task were tested during a late
morning and an early afternoon session. Com-
parisons of the two sessions suggested greater
performance deerement and greater perceived
boredom and monotony among Ss in the after-
noon group than among those in the morning
group. Since several studies (Blake®; Colqu-
hounTM) have reported a slight “post-lunch dip”
in performance on some kinds of tasks, it seemed
possible that the suggestion of greater decrement
among the afternoon group might have been a
reflection of this phenomenon. Alternatively,
the differences between the two groups could
have resulted from a sampling bias, in which the
afternoon group was more susceptible to bore-
dom than the morning group.

The existence of a time-of-day effect could
seriously confound interpretation of the differ-
ences between individuals with respect to rela-