Technical Report Documentation Page 

1. Report No. 2. Government A~ces:sion No. 3. Recipient's Catalog No. 

FAA-AN-76-12 

4. Title and Subtitle 5. Report Dote 

Sm1E EFFECTS OF SLEEP DEPRIVATION ON TRACKING 

PERFORHANCE IN STATIC AND DYNAt-1IC ENVIRONI-1EtHS 6. Performing Organization Code 

8. Performing Organization Report No. 

7. Authorl s) 

William E. Collins, Ph.D. 

9. Performing Orgoni zotion Nome and Address 10. Work Unit No. (TRAIS) 

FAA Civil Aeromedical Institute I 

P.O. Box 25082 11. Contract or Grant No. 

Oklahoma City, Oklahoma 73125 13. Type of Repcrt and Period Covered 

12. ·sponsoring Agency Nome and Address 

·office of Aviation Medicine OAN Report Federal Aviation Administration 

800 Independence Avenue, S.IV. 14. Spon;oring Agency Code 

Washington, D.C. 20591 

15. Supplementary Notes 

This-research was conducted under Task AM-D-75-PSY-54. 

16. Abstract 

The influence of approximately 34 and 55 h of sleep deprivation on performance 

scores derived from manually tracking the localizer needle on an aircraft instrument was assessed under both static (no motion) and dy:1amic (whole-body angular 

acceleration) laboratory conditions. In each of two experiments, 20 young men 

were equally divided into groups of control and sleep-deprived subjects. All tests 

were conducted in an enclosed Stille-Werner rotator in total darkness with the 

exception of the illuminated tracking display. In both experiments, significant 

decrements in dynamic tracking performance were uniformly obtained after 24 h and 

more of sleep loss. Static tracking scores \Vere also impaired but less con- I 

sistently so. In Experimentii, administration of d-amphetamine after 53 h of 

sleep loss produced a sharp drop in error for both static and dynamic tracking. 

Although performance at both types of tasks remained poorer for sleep-deprived 

subjects, their static tracking scores did not differ significantly from control 

subjects 2 h after drug ingestion. Thus, while the drug benefited performance, 

the benefits were only partial ones. Attentional lapses and inefficiency in 

perceptual-motor and information-processing'mechanisms seem to account for the 

deleterious effects of sleep deprivation on performance. Thus, the study indicates 

clear declines in performance scores for an aviation-related task after a night 

without sleep. These negat.i ve effects become generally greater with increasing 

amounts of sleep loss and are more pervasive in motion environments. 

17. Key Words 18. Distribution Statement j 

Sleep Loss and Performance Document is available to the public 

t1otor Effects through the National Technical Information 

Drug Effects Service, Springfield, Virglnia. 22151 

Vestibular 

19. Security Clossif. (of this report) 20. Security Classif. ("f this page) 21. No. of Pages 2~.~ PrJce 

Unclassified Unclassified 

-· -- FNnt DOT F 1700.7 (8-72) Repr<>ducti"n of completed page uuthorized 

SOME EFFECTS OF SLEEP DEPRIVATION ON TRACKING PERFORMANCE 

IN STATIC AND DYNAMIC ENVIRONMENTS 

I.. Introduction. 

Several studies1 •

7•

10 o:f the effects o:f sleep 

deprivation have indicated that attentionallapses 

are related to performance decrements and that 

these lapses increase in :frequency and duration 

with increases in sleep loss. Johnson and X aitoh" 

suggest that such lapses could account :for performance decrements on tasks that require vigilance or motor performance'; :for other types o:f 

tasks, a change in information-processing capability or deficiencies in the :formation o:f memory 

traces may be more adequate explanations o:f 

sleep loss effects. Moreover, many o:f these performance measures are influenced by diurnal 

rhythms10 such that effects o:f sleep loss are likely 

to be more evident in early morning hours. 

Assessments o:f the influence on performance 

o:f altered psychological and physiological states 

including those produced by sleep loss usually 

are made in stationary environments. HoweYer, 

in aviation, important aspects o:f modified mental 

and physical conditions are the effects o:f these 

conditions on performance during motion. Recent work has shown that impeditive effects o:f 

alcoholZ· 4 and other drugs8 •

0 on laboratory tracking per:fonnance were more pronounced when 

the trackers were undergoing whole-body angular 

stimulation than when they were stationary. 

\Vhile motion might influence perfonuance simply as an additional general stressor, the drnginduced increase in tracking error was correlatPd 

with a loss o:f ability to maintain visual fixation 

and thereby inhibit the ocular nystagmus provoked by angular stimulation. It is possible 

that the consequences of sleep loss may produce 

similar effects; some perceived difficulty in maintaining visual fixation folluwing enn mild deThe assistance of (}regory X Constant, Patrida Uant, 

Linda Fort>man, Cissy Lt>nnon, .r. :u. Lentz, and RuthAnn 

Parvin in tlw conduct of this ,;tndy and of Peter L. 

:'\elson for aid in data analysis is gratefully aeknowledged. 

1 

grees of sleep deprivation is a relatively frequent 

anecdotal report. 

The present study comprised two experiments. 

In the first, the effects of approximately 84 h of 

sleep loss were assessed by using performance 

and motion conditions identical to our previous 

work with alcohol and other depressant drugs. 2

•

7

•

8 

The second experiment involnd three modifications: (i) The magnitude of the angular stimulus was halved, ( ii) the time of sleep loss was 

extended to about 55 h, and (iii) the in-fluence 

of an alerting drug was assessed. 

II. Method. 

A. Subjects. Forty male college students, paid 

volunteers ranging in age from 21 to 80 yr, served 

as subjects. Xone had previous laboratory experience involving nstibular stimulation. Half 

the men performed in Experiment I and the 

other half in Experiment II. \Vithin each experiment, the 20 subjects were assigned at random 

to one of two equal-size groups, either a control 

group or a sleep-deprind group. :Subjects were 

asked to abstain from alcoholic drinks for 48 h 

prior to the study and to arrange to have 8 or 

more h of sleep on the night prior to the first 

experimental clay. Subjects were not allowed to 

consume caffeine drinks or to smoke throughout 

the study. 

B. Apparatus. The subjects were required to 

perform on a one-degree-of-freedom compensatory tracking task ( i) during angular acceleration and ( ii) under stationary conditions. The 

tracking task system, described in detail elsewhere,3 consisted of an aircraft localizer glide 

slope indicator and a joystick. The vertical 

needle of the indicator was in ~onstant left-right 

motion, clriYen at changing rates of speed by a 

sinusoidal forcing function with a 14-s period. 

The subject was instructPd to keep the needle 

in the center or null position by making compensatory movements with the joystick. 
Apgular movemen£ of an enclosed cockpit (a 

modified Stille-\Verner rotation device) was accomplished by a vVavetek signal generator that 

programed a triangular ~waveform stimulus with 

a period of 48 s. A peak angular velocity of 

120° /s (Experiment I) or 60° /s (Experiment 

II) was attained in both the clockwise and counterclockwise directions. Thus, for Experiment 

I, the rate of angular stimulation was 10° /s 2 and 

for Experiment II the rate was 5° /s2 • The subject was accelerated at the prescribed rate until 

he reached a velocity .of 120° /s in one direction; 

he was then decelerated through "O" to a velocity 

of 120° /s in the opposite direction, then accelerated again through "O" to 120° /sin the original 

direction, etc. The room was in total darkness 

throughout the testing session with the exception 

of a light source that was focused on the tracking instrument and provided approximately 

1.0 fL of illumination. 

C. Scoring. Deviations of the localizer needle 

from the null position were considered errors; 

a voltage proportional to these deviations was 

electronically integ~>ated over 1-s intervals during the test period and was recorded on a Beckman Type T electroencephalograph. The same 

device was used to record the eye movements of 

the subjects. Horizontal ocular deviations were 

obtained by means of electrodes taped near the 

outer canthi of the subject's eyes; a reference 

electrode was secured on the forehead. Calibrations of eye movements were accomplished with 

two small, alternately flashing lights, horizontally separated to subtencl a visual angle of 

15°. The quality and quantity of nystagmus 

evidenced in the tracings was rated on a 0-5 

scale by an experienced rater ~who had no knowledge of the subject, group, or session being rated. 

D. Procedure. A clay or two before the start 

of the experiment, all subjects received instructions and then participated in a set of familiarization trials that involved 2% min of static 

tracking and 2% min of dynamic tracking. This 

was followed by a formal practice session comprising five cycles of static tracking and five 

cycles of (lynamic tracking (i.e., tracking during 

five 48-s periods of angular acceleration) separated by 3 min of rest. The performance requirements of expe-rimental sessions conducted 

on subsequent days were identical to those of the 

formal practice session. 

2 

In the first experiment, the 2 experimental 

days comprised tests given at about 0900, 1300, 

1700, and 2100 on Day 1 and 0900, 1300, and 

1700 on Day 2. Subjects were exposed to the 

experimental protocol in groups of five. Half 

the control and sleep-deprived subjects always 

performed static tracking prior to dynamic 

tracking; the order was reversed for the remaining subjects. 

In the second experiment, 3 experimental days 

comprised tests given at about 0900, 1300, and 

1700 on Day 1 ; 0900, 1300, and 1700 on Day 2; 

and 0900, 1300, and 1400 on -Day 3. Subjects 

were exposed to the experimental protocol in 

groups of two or three. Each subject was ~dministered a 10-mg capsule of d-amphetamme 

sulphate at 1200 on Day 3. The only information subjects had about the drug was that it was 

one sometimes used to prevent motion sickness. 

In both experiments, nystagmic eye movements 

and performance were recorded throughout the 

experiment; one of the groups of 10 men was 

kept awake throughout the experiment while the 

other group slept at the laboratory (from 2300 

to 0700). The group kept awake was provided 

with a variety of challenging games and activities to prevent soporific states. A monitor was 

constantly with the subjects. Subjects were always encouraged to do their best immediately 

before each static and dynamic performance test. 

Both groups expected the experiment to continue 

for 3-4 h longer than the actual schedule (to 

reduce possible effects of knowing which was the 

last session) . 

III. Results. 

~feans and standard deviations for tracking 

error scores and nystagmus ratings appear in 

Tables 1 and 2 (Experiments I and II respectively). In both experiments, analyses of variance (repeated measures design) 6 ~were conducted 

with difference sco1:es for each measure by using 

scores during the 0900 session on Day 1 as the 

base from which differences '"ere calculated. 

Sessional differences between groups were assessed with simple effects tests. 6 In all cases, the 

.05 level of probability was used as the criterion 

for significance. Static tracking error scores for 

the _practice session and for the first session on 

Dav 1 were about 63 percent of the dynamic 

tra~king error scores in Experiment I (10° /s2 
angular stimulus) and about 90 percent of the 

dynamic tracking error score in Experiment II 

(5o/ s2 angular stimulus). That is, performance 

was better (less error) in the static situation 

than in the more demanding condition of angular 

motion. 

TABLE 1. Means and Standard Deviations for Tracking Error and 

Nystagmus Ratings Obtained in Experiment I 

Control Grou~ Sleee-Deerived Groue 

Static Dynamic Nystagmus Static Dynamic Nystagmus 

Trackin!! Tracking Rating Trackin!l Trackin!l Ratin!! 

Session M SD M SD M SD M SD M SD M SD 

Day 1 0900 809 168 1421 565 1.40 0.88 1226 482 1667 567 1.60 0.61 

1300 964 436 1617 795 1.31 0.90 1285 578 1756 633 1.45 0.64 

1700 949 515 1497 772 1.18 0.74 1257 615 1612 750 0.95 0.50 

2100 1055 608 1294 681 1.08 0.68 1210 513 1584 684 1.13 0.69 

Day 2 0900 936 531 1372 704 0.98 0.93 2021 1273 2664 1592 2.00 1.08 

1300 938 472 1169 639 0.98 1.04 1470 766 2180 1066 1.23 0.74 

1700 823 408 1111 595 0.80 0.67 1467 763 2020 1314 1.48 1.15 

TABLE 2. Means and Standard Deviations for Tracking Error and 

Nystagmus Ratings Obtained in Experiment II 

Control Grou~ S1ee~-De~rived Grou~ 

Static Dynamic Nystagmus Static Dynamic NystagiiUs 

Trackin!! Trackin,!! Ratin!l Trackin!! Trackin!l Ratin!! 

Session M SD !:! SD M SD M SD M SD M SD 

Day 1 0900 1216 462 1317 426 0.61 0.37 1278 403 1413 456 0.95 0.44 

1300 1029 388 1129 439 0.53 0.29 1113 374 1384 448 0.75 0.26 

1700 975 366 1044 436 0.32 0.19 1282 376 1399 367 0.55 0.44 

Day 2 0900 926 344 1131 482 0.51 0.30 1621 385 2051 461 1.15 0.71 

1300 867 378 1015 453 0.44 0.35 1772 599 2346 809 1.00 0.75 

1700 1119 590 1279 859 0.30 0.35 1609 589 2236 855 0.85 0.67 

Day 3 0900 687 327 827 436 0.53 0.29 2688 1070 3096 1020 1.67 0.53 

1200 DRUG 

1300 644 284 742 326 0.44 0.10 1487 1014 1687 1259 1.00 0.67 

1400 588 254 652 279 0.66 1.04 1027 408 1429 521 0.56 o.28 

3 
A. Experiment I. Significant differences were 

obtained during experimental sessions by analyses 

of Yariance for both static and dynamic scores. 

For the latter, there were significant F -ratios for 

groups (p < .05), for sessions (p < .05), and for 

the sessions X groups interaction (p < .01). For 

static tracking, only the interaction term was 

significant (p < .05). 

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DYNAMIC TRACKING 

•---• CONTROL 

Ci----6 SLEEP 

DEPRIVED 

-•, ..... _- ........ 

..... _--· 

,.---DAY ONE-. r-DAY TWO--. 

0900 1300 1700 2100 0900 1300 1700 

STATIC TRACKING 

,.---DAY ONE-. r- DAY TWO-. 

0900 1300 1700 2100 0900 1300 1700 

TEST SESSIONS 

Fwnn; 1.-Changps in tracking <>rror undt>r static (stationary) and dynamic (10°/s' angular accelerations) 

conditions. '!'racking Prror during the 0900 session 

on Day 1 \Yas set at "0"; error scores for subsequent 

sessions \Yere converted to percentages of increase 

or decrease from the "0" level. 

There were no significant differences between 

the control and sleep-deprived groups for either 

static or dynamic tracking on Day 1. However, 

as shown in Figure 1, clear differences between 

the groups became apparent on the second clay. 

Control subjects, in general, showed continued 

performance improvement from the previous day, 

4 

whereas the error scores for sleep-deprived subjects increased sharply during the morning session for both static (p < .01) and dynamic 

tracking (p < .001). These increases were moderated during the two afternoon sessions such 

that the differences between the groups in static 

tracking were not significant, while differences 

between groups in dynamic tracking, although 

reduced, were still significant for both afternoon 

sesswns (p < .01 in both cases). 

Plots of nystagmus scores during dynamic 

tracking rtre presented in Fignre 2. Analysis of 

variance yielded no significant difference among 

the difference scores bet\n~en the two groups, but 

simple effects tests showed that sleep-deprived 

subjects had significantly more nystagmus 

(p<.01) on Day 2 during the 0900 session. 

B. EwpeJ"iment I I. Analyses of vanance 

yielded significant differences on experimental 

days for both static and dynamic tracking scores 

across sessions (p<.01), between groups (p< 

.001), and for the sessions X groups interaction 

(p<.01). 

There were no significant sessional differences 

in comparing the difference scores of the two 

groups on Day 1 for either static or dynamic 

tracking. Clear differences between the groups 

became apparent on the second day (Figure 3). 

Control subjects, in general, showed continued 

performance improvement, whereas the error 

scores for sleep-deprived subjects increased markedly. These increases in error yielded significant 

differences between groups for the dynamic 

tracking condition for all sessions on Days 2 and 

3 (p < .05-p < .001). Static tracking scores differed significantly (p < .01-JJ < .001) behveen the 

groups for all sessions except those at 1700 on 

Day 2 and 1400 on Day 3. The ingestion of 

cl-an'lphebunine on Day 3 had no apparent effect 

on scores for the control group ('vhich continued 

to show some improved performance) but did 

serve to reduce errors for the sleep-deprived 

group during the sessions held 1 and 2 h after 

drug ingestion. Although error scores remained 

significantly higher for sleep-deprived subjects 

during dynamic tracking (p<.01 and p<.05 respectively for sessions 1 and 2 h after drug 

ingestion), the drug. was effective in reducing 

the static tracking error of sleep-deprived sub-
2.5 NYSTAGMUS RATINGS 

(!) 

CONTROL z ·---· 

(f) ~ 2.0 

6 6. SLEEP :J (.) DEPRIVED ~ <( (/) 1.5 (!) 0:: z 

<( <l: 

·-- I- w I-

(f) ~ 1.0 ---·---• .... w .... -. >- _J z - 0.5 ::c 

~ DAY ONE ,-DAY TWO~ 

0 

0900 1300 1700 2100 0900 1300 1700 

TEST SESSIONS 

Fwum: 2.-Ratings of nystagmus obtained during dynamic (l0°/S2 angular accelerations) tracking. 

jects to an insignificant difference from that of 

control subjects during the 1400 session (differences were significant at the .01 level during the 

1300 session). 

Plots of nystagmus ratings across sessions appear in Figure 4. No statistically significant 

differences were obtained for the difference scores 

by analyses of variance. However, simple effects 

tests indicated that sleep-deprived sulJjects had 

significantly more nystagmus output than did 

controls during the 0900 session of Day 3 

(p<.001). 

IV. Discussion. 

In both experiments, significant decrements in 

dynamic tracking performance \Yere uniformly 

obtained after 24 h and more of sleep loss. Static 

tracking scores were less consistently affected; 

viz, sleep-deprived subjects showecl a marked increase in tracking error during the morning session after a night without sleep-probably 

5 

influenced by a circadian effect-but they recovered sufficiently to be not significantly different 

from control subjects during the late afternoon 

sessions in both experiments. 

Following 48 h of sleep loss (Experiment II), 

another marked increase in error scores was apparent for both static and dynamic tracking. 

\Yhile a circadian component probably was a 

contributing factor, the magnitude of the error 

increase argues against the likelihood that enough 

recovery would have occurred to cancel the significant difi'erences between sleep-depri vecl and 

control subjects for either dynamic or static 

tracking in later sessions ha<l an analeptic drug 

not been administered. It is also unlikely that 

an improvement (reduction in error) would have 

occurred among sleep-clepri ved subjects for both 

static and dynamic tracking at 1300 on Day 3 

as compared with VWO on Day 2 if the clrng had 

not been administered (the improvement was 

significant at p<.01 for dynamic tracking error 

by a least significant difference test6 ). 
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DYNAMIC TRACKING 

-----eCONTROL 

tr------0 SLEEP DEPRIVED 

• / / ' 

-•, / ' \ 

..... -- ... '•/ ' \ 

' ' ., ' 

-·-- ,--DAY ONE---.r--DAY TWO---,,-OAY THREE~ 

0900 1300 1700 0900 1300 1700 090~1300 1400 

DRUG 1 hr 2 hr L-...y---J 

POST DRUG 

STATIC TRAc'KING 

--·---·- / --·/ / 

/ • \ 

\ 

' ' ' ' 

·---.... _ .--DAY ONE----,,..-DAY TWO----,rDAY THREE.::,• 

0900 1300 1700 0900 1300 1700 090~1300 1400 

DRUG I hr 2hr L-...y---J 

TEST SESSIONS POST DRUG 

FIGURE 3.-Changes in tracking error under static (stationary) and dynamic (5° ;s' angular accelt>rations) 

conditions. Tracking t>rror during the 0900 >lession 

on Day 1 was set at "0"; error scores for subsequent sessions were converted to percentagE's of 

increase or decrt>ase from tlw "0" leY<'l. Tt>n mg of 

d-amplletamine wei'<' administt>red to all subjects 

at 1200 on Day 3. 

The ingestion of 10 mg of d-amphetamine 

after approximately 53 h of sleep loss produced 

a sharp drop in errors for both static and dynamic tracking. Although some of the performance improvement :from the morning session may 

be attributable to motivational and circadian 

:factors as well as to the drug, the static tracking 

performance o:f sleep-deprived subjects recovered 

sufficiently (although it was still inferior) to be 

6 

not significantly different from that of control 

subjects 2 h after drug ingestion. Dynamic 

tracking scores also improved :for sleep-deprived 

subjects but remained significantly poorer than 

the scores o:f control subjects. Thus, the effect 

o:f the alerting drug was limited; that is, performance o:f the sleep-deprived subjects improved 

in both static and dynamic situations but not to 

the levels o:f the control group, and less effect 

was obtained for dynamic as compared with 

static tracking. ·while an alerting drug may 

have some. beneficial performance consequences 

when used to oppose effects of 53 h or more o:f 

sleep loss, present data indicate that the benefits 

are only partial ones. 

While it would be inappropriate to equate the 

sleep loss o:f the present experiments to small 

doses o:f depressant drugs, comparisons of these 

performance results with results obtained :following the ingestion o:f alcohoF•4 and other depressants8·~ suggest points o:f difference in the 

way that performance decrements are mediated. 

Subjects who had ingested alcohol, secobarbital, 

dramamine, or phenergan in previous studies 

showed significant decrement in performance 

during motion but little or r.o decrement in performance during static tests (it is, o:f course, 

likely that higher closes o:f these drugs would 

have significantly reduced static scores). Eyemovement recordings revealed that these depressants interfered with the ability o:f the 

subjects to use visual-fixation mechanisms to inhibit the nystagmus occasioned by angular accelerations; thus, nystagmus-induced blurring 

o:f the visual field could account :for the increases 

in dynamic performance errors and the absence 

o:f deleterious performance changes in the static 

situation. However, sleep ·loss produced a different effect in that (i) both static and dynamic 

tracking performance declined significantly ( although dynamic tracking scores were more consistently affected) and (ii) increased nystagmus 

activity was not reliably associated with significant performance decrements during motion. In 

the present study, it would appear that both 

information-processing and attentional mechanisms may have been mo~e prominently involved. Clearly, the sleep-deprived group 

occasionally experienced the lapses noted in other 

research. 1 •

5 •7 •10 Several of the sleep-deprived 

subjects reported as early as 0900 on Day 2 that 

the tracking instrument would occasionally 
(!) 2.0 z NYSTAGMUS RATINGS 

(/) ~ •---• CONTROL 

::::> (.) 1.5 

~ <( CJ) 6 6 SLEEP DEPRIVED 

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·- ...... •- ..... ..... ..... --·- ,. --·,. z ........... --..... ::r: r--DAY ONE---'\ ,-DAY TWO ---'\rDAY THREE, 

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0900 1300 1700 0900 1300 1700 090~1300 1400 

DRUG lhr 2hr 

\ I 

v TEST SESSIONS POST DRUG 

FIGURE 4.-Ratings of nystagmus obtained during dynamic (5°/s2 angular accelerations) tracking. 

"black out" or the localizer needle would disappear for brief }Jeriods, or that the fixed glide 

slope indicator on the instrument would be mistaken for the localizer needle. By Day 3, some 

visual hallucinations were reported; e.g., the 

localizer needle appeared to be "dripping," the 

needle took on the appearance of a man, and 

visual scenes appeared to be superimposed on the 

tracking instrument. On some occasions, these 

lapses might have caused a loss of visual fixation 

and thereby increased nystagmic output during 

dynamic tests. But the fact that increased 

7 

nystagmus of the sleep-deprived subjects was not 

a reliable correlate of increased tracking error 

in the dynamic tests (as well as the static tests) 

suggests some additional interference in performance by mechanisms associated with information 

processing or with perceptual-motor systems. 

Thus, this study indicates clear declines in 

performance scores for an aviation-related task 

after a night without sleep. These negative effects become generally greater with increasing 

amounts of sleep loss and are more pervasive in 

motion environments. 
References 

1. Bills, A. G.: Studying Motor Functions and Efficiency. In Andrews, T. G. (Ed.), Methods ot 

Psychology, New York, Wiley, 1958. 

2. Collins, W. E., R. D. Gilson, D. J. Schroeder, and 

F. E. Guedry: l<Jffects of Alcohol Ingestion on 

Tracking Performance During Angular Acceleration. 

JOURNAL OF APPLIJ<JD PSYCHOLOGY, 55:559-

664, 1971. 

3. Gilson, R. D., F. E. Guedry, and A. J. Benson : Influence of Vestibular Stin:mlation and Display 

Luminanct> on the Performance of a Compensatory 

TraCking Task, AEROSPACE l\1EDICIXE, 41:1231-

1237, 1970. 

4. Gilson, R. D., D. .J. Schroeder, W. E. Collins, and 

F. K Guedry: Effects of Different Alcohol Dosages 

and Display Illumination on 'l'racking Performance 

During Vestibular Stimulation, AEROSPACE MEDICINE, 43:656-660, 1972. 

5 .. Johnson, L. C., and P. Xaitoh: The Opt>rational 

Consequences of Sleep Deprivation and Sleep Deficit. 

North Atlantic Treaty Organization Advisory Group 

8 

for Aerospace Research and Development AGARDograph No. 193, 1974. 

6. Kirk, R. E. : Bxperimental Design: Procedures tor 

the Behavioral Sciences, Belmont, California, 

Brooks/Cole, 1968. 

7. Patrick, G. T., and J. A. Gilbert: On the Effects of 

Loss of Sleep, PSYCHOLOGICAL REVIEW, 3:469-

483, 1896. 

8. Schroeder, D. J., W. E. Collins, and G. W. Elam: 

Effects of Secobarbital and d-Amphetamine on 

Tracking Performance During Angular Acceleration, 

ERGOKOJ\IICS, 17:613-621, 1974. 

9. Schroeder, D. J., W. E. Collins, and G. W. Elam: 

Effects of Some Motion Sickness Suppressants on 

'l'racking l't>rformance During Angular Acceleration. 

Paper presented at the 47th Annual Scientific Meeting of the Aerospace Medical Association, Bal 

Harbour, Florida, 1976. 

10. Williams, H. L., A. Lubin, and J. J. Goodnow: 

Impaired Performance With Acute Sleep Loss, 

PSYCHOLOGICAL 1\IOXOGRAPHS, 73, No. 14 

(Whole No. 484), 1959.