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TRANSCRIPT
A3-1U
JAij ('?
THE EFFECT OF MONETARY REWARD AND KNOWLEDGE OF RESULTS
ON COMPLEX-CHOICE REACTION TIMES
THESIS
Presented to the Graduate Council of the
North Texas State University in Partial
Fulfillment of the Requirements
For the Degree of
MASTER OF SCIENCE
By
Terry Barnett Davies, B. A.
Denton, Texas
May, 1975
Davies, Terry B., The Effect of Monetary Reward and
Knowledge of Results on Complex-Choice Reaction Times.
Master of Science (Experimental Psychology), May 1975, 63 pp.,
10 tables, 3 illustrations, 39 titles.
This investigation was designed to determine relative
effects of monetary reward and knowledge of results on
complex-choice reaction time tasks. Subjects were twenty-
five male and thirty-two female undergraduate students.
Apparatus consisted of nine stimulus lights and eight re-
sponse keys. Subjects were required to add the number of
lights presented, subtract the sum from a constant, and press
the correctly numbered response key. Reward subjects re-
ceived twenty-five cents for responses faster than a pre-
determined criterion, and twenty-five cents was deducted
for slower responses. Knowledge of results subjects were
told their reaction times after each trial. Results indi-
cated (1) no significant differences between any conditions,
(2) a significant overall practice effect (.01 level), and
(3) that males were significantly faster than females
(.01 level).
TABLE OF CONTENTS
PageLIST OF TABLES ....... . ............ iv
LIST OF ILLUSTRATIONS ................ v
Chapter
I. INTRODUCTION...... . ..........
General Purpose of StudyHistorical DevelopmentSurvey of LiteratureStatement of ProblemSpecific Purposes of StudyHypotheses
II. METHOD.*................................ 16
SubjectsApparatusExperimental ProcedureExperimental Design
III. RESULTS .. *................................26
Statistical AnalysisTenability of Hypotheses
IV. DISCUSSION OF RESULTS .................... 38
V. SUMMARY AND CONCLUSIONS .0. .. .. .. .... . 50
APPENDIX -*-.-.-.....-.-.-..... . . . . . . . . . . ... 53
BIBLIOGRAPHY................0.0 .... . . .. ......60
iii
LIST OF TABLES
Table Page
I. Stimulus Configurations and Foreperiods...... 21
II. Cut-Off Points in Seconds and Percentageof Projected "Faster" Responses .... . . ... 22
III. Means and Standard Deviations of ReactionTimes for all Conditions............... 27
IV. Summary of Analysis of Variance of the Sexx Motivation x Trial Design................29
V. Summary of Analysis of Variance of the Sexx Motivation x Block Design................32
VI. Means and Standard Deviations of Sex andTrial Block Reaction Times.............. 33
VII. Reward Subjects' Reaction Times on each Trial . . 53
VIII. Knowledge of Results Subjects' Reaction Timeson each Trial.-...-........ . . .......... 55
IX. Control Subjects' Reaction Times on each Trial . 57
X. Means and Standard Deviations of MotivationalCondition and Trial Block Reaction Times . . 59
iv
LIST OF ILLUSTRATIONS
Figure Page
1. Visual Choice Reaction Time Apparatus .......... 16
2. Male and Female Means as a Function ofMotivational Condition ..*............. 28
3. Practice Effect for Males and Females ..o........34
V
CHAPTER I
INTRODUCTION
General Purpose of Study
In general, the objective of the present study was to
incorporate the findings from two areas of psychological
research, reaction time studies and motivational studies, in
order to investigate the motivational effects of knowledge
of results and reward on a choice reaction time (CRT) task.
Historical Development
Among the first reaction time experiments were those
conducted by Helmholtz in 1850, when he attempted to measure
the conduction speed of human sensory nerves by electrical
stimulation. Helmholtz obtained an estimate of the rate of
nerve conduction, but his method was confounded by the
subject's reaction time in that the time measurement was
taken from the moment the stimulus touched the subject's
skin until he responded to the shock by moving his hand.
Helmholtz was, therefore, measuring reaction time, not just
nerve conduction (29). In 1868 Donders attempted to measure
the time of mental processes by requiring subjects to make
an intervening discrimination or choice between the stimulus
and the response. Then, by subtracting the simple reaction
1-
2
time from the choice reaction time, he could determine the
exact time for each mental process (8,29).
Wundt's psychological laboratory followed Donders'
lead and attempted to obtain definite times for mental pro-
cesses such as attention, perception, association and choice
(29). One of Wundt's first students, Cattel, wrote his dis-
sertation on The Time Taken Up By Cerebral Operations. But,
it was Cattel and Dolley in 1893 who concluded that the velo-
city of the "nervous impulse" cannot be measured by reaction
time methods, including Donders t method of "elimination by
subtraction" (8). Thus, it was shown that reaction time ex-
periments did not necessarily have to be tied to the measure-
ment of mental processes but could be an independent area
of study.
Although attempts to link reaction time with mental pro-
cesses have generally proved fruitless, nonetheless, reaction
time tasks have been included throughout early intelligence
tests, have been used in attempts to predict an individual's
general behavior, have been studied in schizophrenics and
manic-depressives and have been predicted based on an indi-
vidual's physique according to Sheldon's conception of endo-
morphic, mesomorphic and ectomorphic factors in body
build (8,10,29).
In his attempts to measure mental processes, Donders
laid the foundation for the study of choice reaction times.
3
He distinguished between three types of reactions: the a,
the b and the c reactions. The a reaction involved a single
stimulus with a single response required each time the stimu-
lus occurred; the b reaction consisted of two stimuli and two
corresponding responses; and, the c reaction had two stimuli
but only one response with the subject responding to one
stimulus and not the other. The a reaction is a simple
reaction time; the b reaction requires stimulus categori-
zation and response selection (choice reaction time); and,
the c reaction requires stimulus categorization only (3,23).
In 1865, Donders and DeJaeger attempted the first study
of the psychological factors influencing simple and choice
reaction times; however, their research was still basically
directed toward the measurement of the mental processes
involved in a reaction time task (8,29).
One of the important derivatives of the early reaction
time studies was the realization that individual differences
in reaction time were often quite varied even when the sub-
ject was "trying his best" throughout the test (8,29).
Although this realization could have lead to the abandon-
ment of reaction time studies, it ultimately resulted in the
investigation of the varying conditions which caused an indi-
vidual's reaction time to fluctuate so greatly. Unfortunately,
the results of these studies have often been as questionable
as those of the early reaction time studies. Thus, reaction
4
time was studied not as a finite measurement of cerebral
operations but as a phenomenon deserving of further
research (8).
Studies during this period of time revealed that some
of the physiological factors which produced a decrease in a
subject's reaction time included an increase in body tem-
perature, an increase in pulse rate and performance of
strenuous physical exercise. Additional studies revealed
physiological factors that resulted in increases in reaction
time. It was shown that anoxia tends to increase an indivi-
dual's reaction time, maintaining a somewhat constant rate,
until the lack of oxygen becomes extreme. Conversely, small
doses of alcohol decrease reaction time, but only for a short
period; eventually, there is an increase in reaction time
with greater amounts of alcohol. Caffein generally has little
effect on simple reaction time but does cause a decrease in
choice reaction time when consumed in large quantities (26,29).
In addition to physiological factors, motivational
factors have also been considered. Cattel found that varying
the subject's incentive would affect subsequent reaction
times (8). The motivational factors considered have varied
from punishment by electrical shock for slow times to
monetary rewards for fast reaction times (16). Many others
since Cattel have investigated various motivational factors,
and their results have been conflicting. These conflicts have
5
been due to the differences in both the motivational factors
utilized from study to study and the various types of reaction
time tasks employed.
Survey of Literature
Cattel (8) was one of the first individuals to note the
effect of motivation on a subject's reaction time. Since
then, the majority of the recent motivational studies con-
cerning reaction time have stemmed from the early work of
Johanson (16). He found that the speed of reaction may be
increased by providing the subject with ongoing knowledge of
his performance. Church and Camp (5) also found that, in a
simple reaction time task, subjects provided with knowledge
of results of performance were significantly faster than
those who were deprived of this knowledge of results.
McCormack, et al. (18) reported identical findings when using
knowledge of results of performance in another simple reaction
time task. But, their study also indicated that, for the
control conditions only, reaction time increased with time
on task. Thus, the knowledge of results, in addition to pro-
viding quicker reaction times, also appears to maintain a
high level of motivation for the duration of the task.
Sipowicz, et al. (22) have obtained similar findings
using knowledge of results and reward in a simple vigilance
task. Their subjects maintained a high level of vigilance in
6
the knowledge of results and reward conditions while the con-
trol conditions had a typical vigilance decrement. Based on
these findings, they concluded that knowledge of results and
reward were effective motivational techniques. In studies by
Weidenfeller, et al. (28), using knowledge of results, and
Lucaccini, et al. (17), employing monetary rewards, the
typical time on task vigilance decrement was not found in
their experimental condition--further evidence supporting
the effect of motivational factors.
In studies dealing with schematic concept formation,
Glasgow, et al. (9) and Pearre and Jones (20) have found that
the performance of their subjects was not significantly
above chance when knowledge of results was not provided. In
another study dealing with schematic concept formation tasks,
Brown, et al. (4) found that the subjects in the knowledge
of results of performance condition performed worse than the
subjects in the control condition. Conversely, Hollier and
Evans (14), in a study of schematic concept formation with
linguaform patterns did not find a negative effect as in the
previously mentioned study; however, findings from their know-
ledge of results of performance conditions were not signi-
ficantly different from their control condition.
In Sternberg's (25) study on character recognition,
knowledge of results of performance had a significant
positive motivational effect. Additionally, monetary
7
incentives were found to increase performance in vigilance
tasks studied by Bergum and Lehr (2) and Smith, et al. (24),
with the results reported to be due to the experimentally
induced changes in the motivational level of the reward
groups. The effects of monetary reward seemed evident in the
past. Edwards (6,7) has stated that money is one of the best
final value measures in that it will fit almost any problem,
it is unambiguous and tangible and it has useful motivating
properties. Furthermore, it has been shown that subjects will
try to maximize their expected financial gain. This maxi-
mization of return and resultant increased motivational
level are of crucial importance in experiments dealing with
problem solving, conceptualizing and decision making type tasks.
In an effort to determine whether knowledge of results
is a motivational factor similar to monetary reward or an
informational factor having secondary motivational influence,
Hardesty, et al. (12) mechanically presented knowledge of
results (information only) while an observer presented know-
ledge of results (information plus evaluative-motivational
input) in a monitoring task. The results indicated that the
subjects in the observer-presented condition were signifi-
cantly better at the monitoring task than either the subjects
in the mechanically-1presented condition or in the control
(no information) conditions. Furthermore, the results of
the mechanically-presented condition were not different from
8
the control condition. These results were interpreted as
indicating that the observer-presented knowledge has an
evaluative-motivational effect on the subject, thereby in-
ducing a greater need to achieve. In similar studies,
Ammons and Ammons (1) have also stated that the processes
related to observer-presented knowledge of results are not
informational but motivational in character.
Church and Camp (5) indicated that a non-significant
finding of their reaction time study was that all reaction
times decreased with time on task (practice effect) with the
greatest decrease in the knowledge of results condition.
Also, Mowbray and Rhoades (19) and Hyman (15) found a signi-
ficant practice effect in their studies of reaction time.
Teichner and Krebs (27) have reported that practice effects
are one result of the number of trials in reaction time
studies. On the other hand, Woodworth and Schlosberg (29)
stated that the average subject continues to reduce his
reaction time over several hundred trials with the largest
practice effect found in the first fifty to one hundred
trials. In addition, these studies showed the practice effect
to be even greater in choice reaction time tasks.
In addition to widely varying individual differences in
reaction times, Goodenough (10) has found a significant dif-
ference between the simple reaction times of males and fe-
males. In these studies, males reacted somewhat more quickly
9
and with a lower variability from trial to trial; however,
a great deal of overlapping between sexes was noted.
Teichner (26) also mentions that the weight of evidence in
reaction time studies indicates that a sex difference
favoring men does exist. In a study by Hodgkins (13), it
was found that a sex difference was greatest at the college
age level. Overall, between the ages of twelve to fifty-four,
the males were found to be significantly faster than fe-
males of the same age. Woodworth and Schlosberg (29) con-
curred with the previous findings stating that males have
shorter reaction times than females of the same age.
Statement of Problem
In the past, most of the reaction time studies con-
cerning different motivational levels have used knowledge
of results of performance or reward in a simple reaction time
task (5,16,18). The effects of the motivational level have
not always been very substantial due to the inherent dif-
ficulty of using a simple reaction time task. The problem
connected with using a simple reaction time task is that the
subject is prohibited from responding much faster regardless
of his level of motivation because of a "ceiling effect."
The "ceiling effect" is a result of the physical limitations
prohibiting a response faster than approximately 140 to 200
milliseconds for a visual stimulus-key response simple reaction
10
time task. Furthermore, the trial to trial variability is
usually greater than the decrease in simple reaction times
due to the motivational factors.
Donders' b reaction time tasks, requiring both stimulus
categorization and response selection, have been explored in
the past; his own experimentation revealed the b reaction
times to be about 100 milliseconds longer than the a
reaction (simple reaction) times (29). However, Gottsdanker
(11) has found that for a simple b reaction (simple-choice
reaction,) the resultant reaction times are no greater than
simple reaction times. But, Broadbent and Gregory (3) and
Rabbitt (21) have stated that in a highly compatible
situation such as those involved in simple-choice reactions,
the usual tendency for reaction time to increase with the
number of alternative responses will not occur. Thus, it
was reasoned that if motivational factors are to be considered
in a reaction time task, the task must be complex enough to
produce significantly larger reaction times in order to
avoid the "ceiling effect." Therefore, the present study
was designed to investigate more fully the general relation-
ship between motivational factors and reaction time by using
a more complex task.
Specific Purposes of Study
The specific purposes of this study were (a) to deter-
mine the relative effects of different motivational factors
11
on reaction time; (b) to ascertain to what extent males would
respond differently from females in terms of reaction time;
and, (c) to ascertain the joint effects of the two major
variables of motivation and sex on reaction time.
Additionally, this study was designed (a) to determine
the relative effects of different motivational factors on
practice effects; (b) to determine to what extent males would
react differently from females in terms of practice effects;
and, (c) to ascertain the joint effects of the two major
variables of motivation and sex on practice effects.
The motivational factors involved were those widely
used in reaction time and vigilance studies--knowledge of
results of performance and monetary reward. The difference
between the motivational levels was considered and a pre-
diction made that the fastest reaction times would be ob-
served in the reward condition, the next fastest times in
the knowledge of results condition and the slowest times in
the control condition. Additionally, the difference
between the motivational levels was considered with respect
to the practice effects. The practice effect was predicted
to be the greatest in the most highly motivating condition
(reward), with the knowledge of results and then the control
condition showing decreasing practice effects.
Hypotheses
This study was designed to test empirically the following
hypotheses:
Hypothesis l.--Subjects in the reward condition will
produce significantly faster mean reaction times than (a) the
subjects in the knowledge of results condition, and (b) the
subjects in the control condition.
Hypothesis 2.--Subjects in the knowledge of results
condition will produce significantly faster mean reaction
times than subjects in the control condition.
Hypothesis 3.--Subjects in the reward condition will
have significantly greater practice effects than (a) the
subjects in the knowledge of results condition, and (b) the
subjects in the control condition.
Hypothesis 4.--Subjects in the knowledge of results
condition will have significantly greater practice effects
than subjects in the control condition.
CHAPTER BIBLIOGRAPHY
1. Ammons, R. B., and C. H. Ammons, "Some Knowledge ofPerformance Concepts," Psychological Reports, 2(1956), 65-66.
2. Bergum, B. 0., and D. J. Lehr, "Monetary Incentives andVigilance," Journal of Experimental Psychology, 67(1964), 197-198.
3. Broadbent, D. E., and M. Gregory, "Donders' B- and C-Reactions and S-R Compatibility," Journal ofExperimental Psychology, 63 (1962), 575-578.
4. Brown, B. R., D. W. Walker, and S. H. Evans, "SchematicConcept Formation as a Function of ConstraintRedundancy and Knowl edge of Resul ts, " Psychonomi cScience, 11 (1968), 75-76.
5. Church, R. M. and D. S. Camp, "Change in Reaction-Timeas a Function of Knowledge of Results," AmericanJournal of Psychology, 78 (1965), 102-106.
6. Edwards, W., "Costs and Payoffs Are Instructions,"Psychological Review, 68 (1961), 275-284.
7. , "Optimal Strategies for Seeking Information:Models for Statistics, Choice Reaction Times, andHuman Information Processing," Journal of MathematicalPsychology, 2 (1965), 312-329.
8. Garrett, H. E., Great Experiments in Psychology, New York,D. Appleton-Century, 1934.
9. Glasgow, J. M., and E. C. Jones, "Effects of Knowledgeof Results on Schematic Concept Formation withLinguaform Patterns," Psychonomic Science, 19(1970), 347.
10. Goodenough, F. L., "The Development of the ReactiveProcess from Early Childhood to Maturity," Journalof Experimental Psychology, 18 (1935), 431-450.
13
14
11. Gottsdanker, R., "Choice Reaction Time and the Natureof the Choice Response," Psychonomic Science, 14(1969)5, 257-258.
12. Hardesty, D., D. Trumbo, and W. Bevan, "Influence ofKnowledge of Results on Performance in a MonitoringTask," Perceptual and Motor Skills, 16 (1963),629-634.
13. Hodgkins, J., "Reaction Time and Speed of Movement inMales and Females of Various Ages," ResearchQuartery 34 (1963), 335-343.
14. Hollier, J., and S. H. Evans, "Schematic ConceptFormation with Linguaform Patterns," PsychonomicScience, 9 (1967), 89-90.
15. Hyman, R., "Stimulus Information as a Determinant ofReaction Time," Journal of Experimental Psychology,45 (1953)3, 188-196.
16. Johanson, A. M., "Influence of Incentive and Punishmenton Reaction-Time," Archives of Psychology, 8(1922), 1-53.
17. Lucaccini, L. F., A. Freedy, and J. Lyman, "MotivationalFactors in Vigilance: Effects of Instructions onPerformance in a Complex Vigilance Task," Perceptualand Motor Skills, 26 (1968), 783-786.
18. McCormack, P. D., F. R. S. Binding, and J. Chylinski,"Effects on Reaction Time of Knowledge of Results ofPerformance," Perceptual and Motor Skills, 14(1962), 367-372.
19. Mowbray, G. A., and M. V. Rhoades, "on the Reduction ofChoice Reaction Times with Practice," QuarterlyJournal of Experimental Psychology, 11 (1959) , 16-23.
20. Pearre, J. C., and E. C. Jones, "Effects of Knowledgeof Results on Schematic Concept Formation,"Psychonomic Science, 12 (1968), 367-368.
21. Rabbitt, P. M. A., "Effects of Independent Variationsin Stimulus and Response Probability," Nature,183 (1959)5, 1212.
15
22. Sipowicz, R. R., J. R. Ware, and R. A. Baker, "TheEffects of Reward and Knowledge of Results on thePerformance of a Simple Vigilance Task," Journalof Experimental Psychology, 64 (1962), 58-61.
23. Smith, E. E., "Choice Reaction Time: An Analysis ofthe Major Theoretical Positions," PsychologicalBulletin, 69 (1968), 77-110.
24. Smith, R. L., L. F. Lucaccini, and M. H. Epstein,"Effects of Monetary Rewards and Punishments onVigilance Performance," Journal of AppliedPsychology, 51 (1967), 411-416.
25. Sternberg, S., "Two Operations in Character Recognition:Some Evidence from Reaction-Time Measurements,"Perception and Psychophysics, 2 (1967), 45-53.
26. Teichner, W. H., "Recent Studies of Simple ReactionTime," Psychological Bulletin, 51 (1954), 128-149.
27. , and M. J. Krebs, "Laws of VisualChoice Reaction Time," Psychological Review, 81(1974), 75-98.
28. Weidenfeller, E. W., R. A. Baker, and J. R. Ware, "TheEffects of Knowledge of Results (True and False) onVigilance Performance," Perceptual and Motor Skills,14, (1962), 211-215.
29. Woodworth, R. S., and H. Schlosberg, ExperimentalPsychology, New York, Holt, 1958.
CHAPTER II
METHOD
Subjects
The subjects were twenty-six male and thirty-two female
students enrolled in undergraduate psychology classes at
North Texas State University. The mean age of the males was
21.2 years and the mean age of the females was 22.3 years.
Apparatus
A visual choice reaction time apparatus as shown in
Figure 1 was used to allow presentation of up to nine stimulus
lights at any one time.
)2clear stimulus
lights
red responsebuttons
Fig. 1 -- Visual choice reaction time apparatus
In addition to allowing any number of lights to be presented,
the stimulus lights could also be presented in any order by
means of jacks located on the experimenter's side of the
apparatus. The apparatus shown in Figure 1 could also be
16
0 1.6 46 410 0 0 00 0
17
independently programmed to select any one of the eight red
response buttons as the correct answer; this was accomplished
by means of a rotary switch located on the experimenter's
side of the apparatus. The visual choice reaction time
apparatus shown in Figure 1 was grey in color and measured
17 1/2 inches wide and 8 inches high.
A stop clock timer (Clock/Counter Model 54519, Lafayette
Instrument Company) was connected to the reaction time
apparatus to permit measurement of the subjects' reaction
time to the nearest hundredth of a second.
A twenty-eight-volt D.C. power supply was connected to
the reaction time apparatus and a start button. The start
button turned on the preselected stimulus lights and started
the clock timer. When the subject responded by pressing the
correct response button, the stimulus lights and the clock
timer were turned off. Also, a standard stopwatch was used
to measure the foreperiods.
Experimental Procedure
Control Condition Instructions
All subjects were given the following verbal instructions
which constituted the control condition; additional
instructions to be described were given to subjects in the
other two conditions.
In this experiment, I will measure the speedwith which you can press a key in response to a
18
number of stimuli. There are nine lights and eightkeys on the apparatus in front of you. Each ofthese lights counts as one stimulus. The keys arenumbered from zero to seven starting from yourleft. Before each trial, I will say "ready" andshortly thereafter the lights will come on. Youare to count the number of lights and subtract thecount from the number eight. Quickly press thekey which represents the correct answer to themathematical problem with the index finger of yourdominant hand. If you press the wrong key, onethat does not turn the lights off, correct your-self as quickly as you can. In between trials,keep your hand resting on the table in front ofthe apparatus. Any questions?
Knowledge of Results Instructions
In addition to the above instructions, the subjects in
the knowledge of results condition were given the following
verbal instructions: "Immediately after each trial, you will
be told how many seconds it took you to press the correct
key after the stimuli were presented."
Reward Condition Instructions
The reward condition subjects were given the following
additional verbal instructions:
A pencil and a sheet of paper have beenprovided; the paper has two columns, one labeled'faster' and one labeled 'slower.' After'eachtrial, I will tell you if your response wasfaster of slower than a predetermined responsetime. You are to keep a stroke tally of theresponses in the proper column; when all thetrials have been completed, you will receivetwenty-five cents for every response in the'faster' column that exceeds the number in the'slower' column. You can earn as much as $5.25in the fifteen minutes that you will be here.That is equivalent to earning $21.00 per hour.
19
After receiving the appropriate instructions, each
subject was given twenty-one trials. For each trial problem,
the experimenter said "ready", waited one, two, or three
seconds (the foreperiod), and then pressed the start button.
The subject's correct response turned off the stimulus lights
and the timer. The experimenter then recorded the subject's
reaction time to that particular trial problem.
The trial problems were presented at a rate of no less
than twenty-five and no more than forty seconds between
trials.
The foreperiods, the time between the "ready" signal
and the onset of the stimulus, were randomly assigned to
each of the trial problems. The trial problems consisted
of two random assignments: the number of lights presented
and which lights would be presented. The number of lights
presented determined the correct response: if two lights
were turned on then the correct response was six (eight
minus two); if five lights were turned on then the correct
response was three (eight minus five); and, if eight lights
were turned on the correct response was zero (eight minus
eight). Eight different answers would have been possible
on the apparatus using buttons numbered zero through seven,
but the number one button malfunctioned at the beginning
of this study and, therefore, was not used. The seven
remaining responses (0,2,3,4,5,6,and 7) were randomly
20
assigned within three blocks of seven trials each. Thus,
each response was represented once in the first seven,
middle seven, and final seven trials.
For each trial problem, the lights which were turned on
(stimulus configuration) were also randomly assigned. Thus,
if the number of lights to be presented was three, three
lights were randomly assigned to that particular problem.
The lights were numbered one through nine, from left to
right, on the experimenter's side of the apparatus only.
For purposes of illustration, Table I contains the
stimulus configurations and foreperiods for all twenty-one
trial problems used in this experiment.
21
TABLE I
STIMULUS CONFIGURATIONS AND FOREPERIODS
Number ofBlock Trial Stimuli Stimulus Foreperiod Correct
Presented Configuration Response
1 2 1,3 3 62 4 4,7,8,9 2 43 5 1,2,4,5,8 3 3
1 4 6 1,2,6,7,8,9 2 25 8 1,2,3,4,5,6,7,8 2 06 1 3 1 77 3 1,5,9 1 5
8 8 1,3,4,5,6,7,8,9 3 09 2 4,7 2 6
10 5 1,2,6,7,9 1 32 11 1 7 3 7
12 3 2,3,8 2 513 4 3,4,6,8 1 414 6 2,4,5,7,8,9 3 2
15 6 3,4,6,7,8,9 1 216 2 8,9 1 617 5 3,4,5,6,7 2 3
3 18 3 2,3,6 3 519 1 6 2 720 8 2,3,4,5,6,7,8,9 1 021 4 1,4,7,8 3 4
The subjects in the knowledge of results condition
were told their actual response time after each trial. The
subjects in the reward condition were told to put a stroke
under the "faster" column if their response was equal to or
faster than 1.80 seconds and a stroke under the "slower"
column if their response was slower than 1.80 seconds. At
22
the completion of the experimental session, the reward
subjects were instructed to total each column and subtract
the "slower" responses from the "faster" responses. The
experimenter then paid the subjects at the rate of twenty-
five cents for every response in the "faster" column that
exceeded the number of responses in the "slower" column as
per the reward condition instructions.
The cut-off point of 1.80 seconds was based on the first
four subjects run in the present experiment. The first four
subjects were not in the reward condition and consisted of
one male and one female in each of the control and knowledge
of results conditions. The 1.80 second cut-off point was
selected to reward the subjects with a "faster" response
forty-three per cent of the time. The cut-off points
considered and their projected percentage of "faster"
responses are presented in Table II.
TABLE II
CUT-OFF POINTS IN SECONDS AND PERCENTAGEOF PROJECTED "FASTER" RESPONSES
Cut-off Points Percentage of Projected "Faster" Responses
1.60 . . . . . . . . . . . . . . . . 351.70 . . . . . . . . . . . . . . . . 381.80 . . . . . . . . . . . . . . . . 431.90 . . . . . . . . . . . . . . . . 452.00 . . . . . . . . . . . . . . . . 51
23
Although Church and Camp (1) successfully used a
similar criterion in their study that provided thirty-three
per cent "faster" responses, in this study forty-three per
cent projected "faster" responses was selected as the
criterion. It was decided to use a higher cut-off point in
this study due to the right minus wrong payoff scheme, a
method not used by Church and Camp (1). Because of this
payoff scheme, the reward condition subjects had to have
more than fifty per-cent "faster" responses in order to
receive any monetary reward. Since the projection was
calculated from the two lower motivating conditions,
knowledge of results and control, it was decided to use a
payoff rate of less than fifty per cent anticipating that
the motivation of a monetary reward would result in achieve-
ment of a greater percentage of "faster" responses for the
subjects in the reward condition. Unfortunately, the 1.80
second cut-off point ultimately selected actually yielded
only an average of forty-six percent "faster" responses.
The subjects were randomly assigned to one of the
three motivation conditions: reward, knowledge of results
and control.
Experimental Design
The basic design was a three-dimensional analysis of
variance in which the three major factors and their
respective treatment categories were: sex (male-female);
24
motivation (reward-knowledge of results-control); and trials
(twenty-one individual or three blocks of seven each). The
dependent variable was the subject's reaction time for each
of the twenty-one trials.
For the reaction time analysis, the individual trials
were used in a 2 x 3 x 21 three-dimensional analysis of
variance, and for the practice effect analysis, the subjects'
three block means were used in a 2 x 3 x 3 three-dimensional
analysis of variance. The block means were derived from each
subject's reaction times for the first seven, middle seven
and final seven trials.
CHAPTER BIBLIOGRAPHY
1. Church, R. M., and D. S. Camp, "Change in Reaction-Timeas a Function of Knowledge of Results," AmericanJournal of Psychology, 78, (1965) , 102-106.
25
CHAPTER III
RESULTS
Statistical Analysis
The results obtained and the statistical analyses of
those results are reported in the present chapter. The
major objective was to determine the joint and separate
effects of motivational level and sex of the subjects on
their reaction times to a complex choice reaction time task.
The secondary objective was to ascertain the relative effects
of these same variables on practice effect in which the
twenty-one trials were divided into three blocks consisting
of: the first seven, the middle seven and the final seven
trials. The present chapter has been divided into two major
subsections, each one corresponding to the two major analyses.
The reaction times for all subjects for each trial are
presented in the appendix.
Reaction Time
Using each male and female subject's reaction times,
means and standard deviations were obtained for each
condition, for all conditions combined, and for all subjects
in each condition. The means and standard deviations are
presented in Table III.
26
27
TABLE III
MEANS AND STANDARD DEVIATIONS OF REACTIONTIMES FOR ALL CONDITIONS
MotivationalConditionSex Statistic Reward Knowledge Control Main Effect
of Results --Sex
Mean 2.10 2.10 2.15 2.11
Male SD 1.29 1.17 1.49 1.33
N 8 9 9 26
Mean 2.68 2.57 2.17 2.48
Female SD 1.97 1.83 1.36 1.76
N 11 11 10 32
Mean 2.44 2.35 2.16 2.32Main
Effect--, SD 1.74 1.58 1.42 1.59Motivation
N 19 20 19 58
In reference to Table III, a very prominent finding was
the fact that the main effect mean for females (2.48) was
somewhat higher (slower reaction time) than the main effect
mean for males (2.111). Additionally, the main effect means
for the two experimental groups (2.44 and 2.35) were also
higher than the main effect mean for the control group (2.16).
28
In the interest of clarity, the male and female means
for each motivational condition from Table III are
graphically presented in Figure 2.
2.8
2.7 FemalesE
2.6
o -o 2.5
' e 2.3+.) 0
u 2.4
ra)
Qj 2.2
2.1 Males
2.0 -
Reward Knowledge ControlMotivational Condition
Fig. 2--Male and female means as a function ofmotivational condition.
Inspection of Figure 2 reveals that the females were
generally slower in their reaction times than were the males
in all motivational conditions with the least difference
between the sexes being reflected by the control condition
subjects. However, the females achieved their fastest
reaction times, and the males displayed their slowest
reaction times in the control condition, but the difference
appeared to be very slight.
29
The required assumption of homogeneity of variance,
underlying the use of the statistical design, was tested by
Hartley's Fmax statistic as presented by Winer (1). The
observed value of Fmax was 2.83 which did not exceed the
critical value of Fmax = 6.92 (df = 6,10, p = .05); thus,
the hypothesis of homogeneity of variance was regarded
tenable; therefore, an analysis of variance was then
performed on the basic criterion scores.
The reaction times were then placed in the sex x
motivation x trials analysis of variance scheme and analyzed.
A summary of the analysis of variance performed on these
data is presented in Table IV.
TABLE IV
SUMMARY OF ANALYSIS OF VARIANCE OF THESEX x MOTIVATION x TRIAL DESIGN
Source of Variation SS df MS F
Between subjects 332.38 57 . .Sex 37.48 1 37.48 7.47**Motivation 11.64 2 5.82 1.16Sex x motivation 17.81 2 8.90 1.77Error between 260.98 52 5.02
Within subjects 2737.47 1160 . .Trial 665.92 20 33.30 18.36**Sex x trial 32.46 20 1.62 0.90Motivation x trial 62.20 40 1.56 0.86Sex x motivation
x trial 56.51 40 1.41 0.78Error within 1886.22 1040 1.81 .
**Significant at .01 level
30
Adopting a p = .01 level of significance as critical,
the appropriate value for the test between the main effect
means for sexes was F = 7.17 (df = 1,52). Since the
observed F ratio of 7.47 was larger than the critical F value
the difference between the male and female mean reaction
times was shown to be statistically significant. Thus, on
an average basis over all trials as a whole, the males
reacted significantly faster (M = 2.11) than did the females
(M = 2.48) regardless of motivational conditions. The other
significant main effect difference was the within trial F
ratio of 18.36 which also exceeded the p = .01 level of
significance with a critical value of F = 1.89 (df = 20,
1040). The latter finding indicates that at least two of
the twenty-one trial problems were significantly different
in the amount of time required to respond. This significant
difference within subjects' trials was most probably a
result of: (a) a difference in complexity level between
various trial problems, and/or (b) a practice effect, to be
discussed in the following section.
Practice Effect
As a subject becomes familiar with the task and apparatus
in any experiment, the usual result is an improvement in the
performance of that task. In a reaction time task, the
practice effect is evidenced by progressively faster reaction
times as the number of trials increases.
31
Using the subjects' reaction times, the preceding analysis
of variance indicated that at least two of the twenty-one
trial problems were significantly different in the amount of
time required to respond. As was stated earlier, this
difference could be due to various complexity levels of the
trial problems, a practice effect, or some combination of the
two. The effects of the seven different complexity levels
were equalized by presenting each level of complexity
(response) to the subjects three times, once in each block of
seven trials. Thus, by obtaining means for each subject for
the three blocks, the complexity levels were equalized and
any difference between the blocks showing a decrease toward
the last block should be due to the practice effect.
Using each subject's trial block means as criterion
scores, a 2 x 3 x 3 (sex x motivation x block) analysis of
variance was performed. Table V contains a summary of the
analysis.
32
TABLE V
SUMMARY OF ANALYSIS OF VARIANCE OF THESEX x MOTIVATION x BLOCK DESIGN
Source of Variation SS df MS F
Between subjects 47.48 57 .Sex 5.36 1 5.36 7.47**Motivation 1.66 2 0.83 1.16Sex x motivation 2.54 2 1.27 1.77Error between 37.28 52 0.72
Within subjects 44.15 116 .Block 14.19 2 7.09 27.11**Sex x block 0.88 2 0.44 1.68Motivation x block 0.62 4 0.16 0.59Sex x motivation
x block 0.26 4 0.07 0.25Error within 27.22 104 0.26
**Significant at .01 level
Adopting a p = .01 critical level of significance, the
appropriate value for the test between the sexes was F = 7.17
(df = 1,52). Since the observed F ratio of 7.47 was larger
than the critical F value, the difference between the male
and female block means was shown to be statistically
significant. Thus, with the trial complexity equalized and
on an average basis, the males reacted faster (M = 2.11)
than did the females (M = 2.48).
The within subjects block F ratio of 27.11 was also
statistically significant, exceeding the p = .01 level of
significance with a critical F value of F = 4.82 (df = 2,104).
33
Therefore, with the trial complexity equalized in this
analysis, at least two of the blocks were significantly
different in the amount of time required to respond. Thus,
a significant overall practice effect was in evidence.
There were no significant interactions, but both sex
and trial blocks were significant. Since only these two
variables were significant, their corresponding means are
included in the text as reflected in Table VI. The
remaining means are presented in the appendix.
TABLE VI
MEANS AND STANDARD DEVIATIONS OF SEXAND TRIAL BLOCK REACTION TIMES
Sex Statistic Trial Block Main Effect
1 2 3 -- Sex
M 2.41 2.06 1.88 2.11Male SD 0.65 0.51 0.42 0.57
N 26 26 26 78
M 2.96 2.39 2.09 2.48Female SD 0.79 0.75 0.62 0.80
N 32 32 32 96
Main M 2.71 2.24 2.00 2.32Effect SD 0.77 0.67 0.55 0.73
-- Blocks N 58 58 58 174
Inspection of Table VI reveals that for both sexes the
second block mean is lower than the first and the third
block mean is lower than the second. Thus, the significant
34
difference between the blocks as indicated by the analysis
of variance in Table V is due to a practice effect.
The simple effect means from Table VI are shown
graphically in Figure 3.
3.0 ~Females
E 2.8
'1e
4 U 2.4 MalesU CD)
2.2
2.0
1.82 3
Block
Fig. 3--Practice effect for males and females
Inspection of Figure 3 reveals the significant difference
between the sexes as shown in Tables IV and V and also
reveals the significant practice effect as shown in Table V.
Tenability of Hypotheses
Hypothesis 1 stated that the subjects in the reward
condition would produce significantly faster mean reaction
times than; (a) the subjects in the knowledge of results
condition, and (b) the subjects in the control condition.
Hypothesis 2 of the present study stated that the subjects
in the knowledge of results condition would produce
35
significantly faster mean reaction times than subjects in
the control condition.
Hypotheses 1 and 2 were rejected because, as Table IV
indicates, no significant difference existed between any of
the motivational conditions. The between subjects
motivational condition observed F ratio was 1.16 with a
critical value of F = 3.18 (df = 2.52, p = .05). These
results indicated that the relative effects of the
motivational variables used in the present study were not
significantly different.
Table IV also indicates a significant difference
between the male and female subjects with an observed F ratio
of 7.47 with a critical value of F = 7.17 (df = 1,52,
p = .01). Because of the significant difference between the
sexes in the present study, Hypotheses 1 and 2 were also
considered with this sex difference in mind. Hypotheses 1
and 2 were still rejected because the sex x motivation
interaction F ratio from Table IV of 1.77 was less than the
critical value of F = 3.18 (df = 2,52, p = .05).
Hypothesis 3 stated that subjects in the reward
condition would have significantly greater practice effects
than: (a) the subjects in the knowledge of results condition,
and (b) the subjects in the control condition. Hypothesis 4
of the present study stated that subjects in the knowledge
of results condition would have significantly greater
36
practice effects than subjects in the control condition.
Table V indicates that no significant difference existed
between any of the motivational conditions in terms of block
mean reaction times. The between subjects motivational
condition observed F ratio was 1.16 with a critical value of
F = 3.18 (df = 2,52, p = .05). These results indicated that
in terms of block mean reaction times, the relative effects
of the motivational variables were not significantly
different. Since the motivational conditions were not
significantly different, Hypotheses 3 and 4 were rejected.
Further inspection of Table V, however, indicates that
a significant overall practice effect occurred. This
significant practice effect was evidenced by: (a) the
observed within subjects block F ratio of 27.11 which
exceeded the critical value of F = 4.82 (df = 2,104,
p = .01); and, (b) the progressively faster block reaction
times as shown in Figure 3.
CHAPTER BIBLIOGRAPHY
1. Winer, B. J., Statistical Principles in ExperimentalDesign, New York, McGraw-Hill Book Company, 1962.
37
CHAPTER IV
DISCUSSION OF RESULTS
The results of this study do not appear to be in agree-
ment with the results of most reaction time and vigilance
studies. Conflicting evidence will be indicated and attempts
to account for the differences between the present study and
those of others are presented in the following paragraphs.
Hypothesis 1 stated that subjects in the reward condition
would produce significantly faster mean reaction times than
would the subjects in both the knowledge of results condition
and the control condition. The results of this study have
indicated no significant difference between any of the moti-
vational conditions; therefore, the effects of the moti-
vational variables used in this study were not statistically
different. This finding is in direct disagreement with the
following vigilance studies conducted in the past using mone-
tary rewards identical in design to those used in the present
study. Bergum and Lehr (3) rewarded their subjects twenty
cents for each correct response and twenty cents was deducted
for each incorrect response. Smith, et a!. (24), using the
twenty-cent condition, plus an additional ten-cent condition,
obtained results indicating that the twenty-cent condition
was significantly higher than the ten-cent condition
38
39
and the ten-cent condition higher than the control group.
Sipowicz, et al. (23) gave each reward condition subject
three dollars and then deducted increasing amounts with
each miss or incorrect response. Lucaccini, et al. (17)
paid the reward subjects a flat rate of two dollars, with
no deductions, and found the reward condition performing
significantly better than the controls.
The results of the present experiment not only disagreed
with the preceding studies, but conversely, the reward
condition performed at a slower overall rate than any of the
other motivational conditions. Because the reward design was
essentially identical to several of the above designs,
this finding may have been due to the introduction of a
complex-choice reaction time task. The specifics of the
complex-choice reaction time task will be discussed later
in this chapter.
Hypothesis 2 stated that subjects in the knowledge of
results condition would produce significantly faster mean
reaction times than subjects in the control condition. The
results of the present study disagreed-with all of the
following simple reaction time studies (and most of the
following vigilance studies) conducted in the past. Church
and Camp (6) and McCormack, et al. (18) presented knowledge
of results by way of a green light for a "faster" response
and a red light for a "slower" response. Johanson (15)
40
provided his subjects with ongoing knowledge of their per-
formance similar to that used in this study. The following
are vigilance studies which disagree with the present study.
In experiments by Sipowicz, et al. (23) and Weidenfeller,
et al. (29) in which knowledge of results was provided by
lights similar to the preceding reaction time studies,
the results indicated that knowledge of results significantly
improved vigilance performance. Hardesty, et al. (11) found
that when presenting knowledge of results mechanically, as
with the lights, performance was significantly poorer than
when the knowledge of results was provided by an individual
who was present in the experimental situation.
The results of the present study agree with some con-
cept formation experiments but disagree with others. More
specifically, Glasgow and Jones (9) and Pearre and Jones (22)
found that knowledge of results had a positive motivational
effect in that their knowledge of results experimental
subjects performed significantly above chance. On the other
hand, Brown, et al. (5) found negative effects since their
knowledge of results condition subjects performed worse
than their control condition subjects. Hollier and Evans (13)
found that a knowledge of results treatment was not signi-
ficantly different in performance from a control condition.
The two preceding studies generally agree with the present
study in that the knowledge of results condition was not
41
significantly different from the control condition, but it
was slower than the control condition for the females only.
In Sternberg's (25) study of character recognition, the
subjects in the knowledge of results condition were told
their actual reaction times, as in the present study, but
the knowledge of results had a significantly positive moti-
vational effect, unlike the present study.
In the present study, it will be recalled that knowledge
of results was provided by giving the subject his actual
reaction time after each trial; this method is identical to
the method used in one of the preceding studies and similar
to others. The results may have been due to the method of
presentation of the knowledge of results and/or due to the
complex-choice reaction time task utilized in this experiment.
Again, the specifics of the complex-choice reaction time task
will be discussed later in this chapter.
Hypothesis 3 stated that subjects in the reward con-
dition would experience significantly greater practice effects
than would subjects in the knowledge of results condition and
the control condition. Hypothesis 4 stated that subjects in
the knowledge of results condition would have significantly
greater practice effects than subjects in the control con-
dition. The present study revealed significant practice
effects but no significant difference between the motivational
conditions; thus, both Hypotheses 3 and 4 were rejected. In
42
a simple reaction time task, Church and Camp (6) found
non-significant practice effects; but, unlike the present
study, they indicated that the practice effect was not evi-
dent in the control condition. In another simple reaction
time study using knowledge of results, McCormack, et al. (18)
found a significant practice effect. And, in a simple vigi-
lance task by Sipowicz, et al. (23), the reward and knowledge
of results conditions showed evidence of a practice effect
unlike their control condition. Teichner and Krebs (28) and
Woodworth and Schlosberg (30) stated that in a choice re-
action time task, the practice effect will be evident as an
effect of the number of trials. Their statements do agree
with the significant practice effect found in this study as
evidenced by Figure 3. Also consonant with present results
were those of Mowbray and Rhoades (21) in which it was
stated that in a choice reaction time task requiring a key
to be pressed in response to stimuli lights, a practice
effect will be present in all conditions. A study by Hyman
(14) states that all subjects showed a significant practice
effect from series to series, which is also in agreement
with the findings of the present study.
Hypotheses 3 and 4 were rejected because no significant
difference existed between any of the motivational conditions
in the present study. However, a significant overall practice
effect was evidenced in this study which agrees with the
43
majority of similar experiments reported in the literature.
A practice effect is predicted by a majority of experimenters,
especially in a choice reaction time task; but, unlike the
present study, the practice effects have not always been
significant. The rejection of Hypotheses 3 and 4 was due to
the motivational variables having no significant effect.
The results of the present study are in absolute agree-
ment with previous findings of a sex difference in reaction
time tasks. Males were significantly faster than females
which concurs with the findings of Goodenough (10). She
stated in 1935 that a significant difference exists between
the simple reaction times of males and females with the
males reacting more quickly. Teichner (27) stated that the
weight of the evidence in reaction time studies indicates
that a sex difference does exist and that men are the faster
responding of the sexes. Woodworth and Schlosberg (30) also
stated that males have faster reaction times than females of
the same age. Finally, in a simple reaction time study by
Hodgkins (12), males were found to be significantly faster,
with the greatest difference at the college age level. Thus,
it should be concluded that a significant sex difference re-
mains despite the reaction time task required.
It seems reasonable to hypothesize that most of the non-
significant and conflicting results found in the present
study appear to be due to the type of reaction time task
44
utilized. The predictions from the literature do not indi-
cate that a more complex task should show any difference in
results than a simple reaction time task. This may be because,
in the past, the choice reaction time tasks, similar to
Donders' b reaction, were much simpler than the complex-
choice reaction time task employed in this study. The complex-
choice reaction time task in this study was designed with
the straightforward predictions of several experimenters in
mind. In 1885 Merkel (19) stated that for a choice reaction
time task, the reaction time would increase as the number of
possible alternative signals which could be presented in-
creases. While Brebner and Gordon (4) recently stated that,
when the ensemble size is increased and all items are pre-
sented with equal frequency, the stimulus situation is
changed in two ways. First, more separate categories are
presented to the subject and, second, the probability that
a particular response will be required is reduced. The re-
sultant increase in reaction time could be due to reduced
signal probability, an increase in the number of categories
to be identified or an interaction of both effects. However,
Brebner and Gordon (4) did not differentiate between the
results obtained from more complex choice reaction time
tasks and those of simple reaction time tasks. Falmagne (8)
and Andreas (1) also predict longer reaction times when the
number of stimuli presented and responses required are
45
increased; but, they do not predict any difference other
than longer reaction times. It is conceivable that a com-
plex-choice reaction time task, such as the one used in
the present study, would not follow the predictions of a
simple reaction time study.
The task in the present study was designed to replicate
previous tasks with the exception of one factor, the total
time required to respond to each stimulus configuration. As
suggested by Behar and Adams (2), a ready signal was used
before each stimulus presentation identical to the ones
used in most reaction time studies. Variable foreperiods of
one, two or three seconds were used, as found in the
majority of reaction time studies and as suggested by
Moss (20). The stimuli were presented with lights and the
response was a standard key response, both of which are
used in the majority of reaction time studies. Emerson (7)
suggested that the mean is the most reliable reaction time
statistic providing the best gauge of the aspects of
variation of experimental parameters; thus, the mean was em-
ployed in this study as the major statistic.
After considering all the aforementioned studies, the
major difference still remains as the actual task required,
the complex-choice reaction time task. Laming (16) states
that most of the time required to respond to a choice
reaction time task is dominated by the time spent in
46
choosing a response, while Stone (26) breaks the choice
reaction time down into three components: input time,
decision time and motor time, with the decision time cor-
responding to Laming's (16) time spent in choosing a
response. In all choice reaction time studies and in the
present study, the decision time is the variable factor,
from trial to trial.
The design of the present experiment was identical in
most respects to the design of the majority of choice re-
action time studies with the major difference being the
length of the decision time. The results were in direct
conflict with previous results with the exception of the
difference in sex and the overall practice effect. Thus,
it is suggested that a complex-choice reaction time task
such as that used in the present study will not produce
results identical to simple and simple-choice reaction
time studies. Accordingly, the complex-choice reaction time
task does not appear to be classifiable into the same
category as all other reaction time studies.
CHAPTER BIBLIOGRAPHY
1. Andreas, B. G., Experimental Psychology, New York,John Wiley and Sons, Inc., 1972.
2. Behar, I., and C. K. Adams, "Some Properties of theReaction-Time Ready-Signal," American Journal ofPsychology, 79 (1966), 419-426.
3. Bergum, B. 0., and D. J. Lehr, "Monetary Incentivesand Vigilance," Journal of Experimental Psychology,67 (1964), 197-198.
4. Brebner, J., and I. Gordon, "The Influence of SignalProbability, and the Number of Non-Signal Categorieson Selective Response-Time," Quarterly Journal ofExperimental Psychology, 16 (1964), 56-60.
5. Brown, B. R., D. W. Walker, and S. H. Evans, "SchematicConcept Formation as a Function of ConstraintRedundancy and Knowl edge of Resul ts," Psychonomi cScience, 11 (1968)7, 5-76.
6. Church, R. M., and D. S. Camp, "Change in Reaction-Timeas a Function of Knowledge of Results," AmericanJournal of Psychology, 78 (1965), 102-106.
7. Emerson, P. L., "Simple Reaction Time with MarkovianEvolution of Gaussian Discriminal Processes,"Psychometrika, 35 (1970), 99-109.
8. Falmagne, J. C., "Stochastic Models for Choice ReactionTime with Applications to Experimental Results,"Journal of Mathematical Psychology, 2 (1965), 77-124.
9. Glasgow, J. M., and E. C. Jones, "Effects of Knowledgeof Results on Schematic Concept Formation withLinguaform Patterns," Psychonomic Science, 19(1970), 347.
10. Goodenough, F. L., "The Development of the ReactiveProcess from Early Childhood to Maturity," Journalof_ Experimental Psych oIoy 18 (1935), 431-450.
47
48
11. Hardesty, D., D. Trumbo, and W. Bevan, "Influence ofKnowledge of Results on Performance in a MonitoringTask," Perceptual and Motor Skills, 16 (1963),629-634.
12. Hodgkins, J., "Reaction Time and Speed of Movement inMales and Females of Various Ages," Research Quarterly,34 (1963), 335-343.
13. Hollier, J., and S. H. Evans, "Schematic ConceptFormation with Linguaform Patterns," PsychonomicScience, 9 (1967), 89-90.
14. Hyman, R., "Stimulus Information as a Determinant ofReaction Time," Journal of Experimental Psychology,45 (1953), 188-196.
15. Johanson, A. M., "Influence of Incentive and Punishmenton Reaction-Time," Archives of Psychology, 8 (1922),1-53.
16. Laming, D. R., Information Theory of Choice-ReactionTime, New York, Academic Press, 1968.
17. Lucaccini, L. F., A. Freedy, and J. Lyman, "MotivationalFactors in Vigilance: Effects of Instructions onPerformance in a Complex Vigilance Task," Perceptualand Motor Skills, 26 (1968), 783-786.
18. McCormack, P. D., F. R. S. Binding, and J. Chylinski,"Effects on Reaction Time of Knowledge of Results ofPerformance," Perceptual and Motor Skills, 14(1962), 367-372.
19. Merkel, J., "Die Zeitlichen Verhaltnisse derWillensthatigkett," Philosophical Studies, 32(1885),73-127. Cited by Woodworth, R. S., and H. Schlosberg,Experimental Psychology, New York, Holt, 1958.
20. Moss, S. M., "Changes in Preparatory Set as a Functionof Event and Time Uncertainty," Journal of ExperimentalPsychology, 80 (1969), 150-155.
21. Mowbray, G. A., and M. V. Rhoades, "On the Reduction ofChoice Reaction Times with Practice," QuarterlyJournal of Experimental Psychology, 11 (1959), 16-23.
22. Pearre, J. G., and E. C. Jones, "Effects of Knowledge ofResults on Schematic Concept Formation," PsychonomicScience, 12 (1968), 367-368.
49
23. Sipowicz, R. R., J. R. Ware, and R. A. Baker, "The Effectsof Reward and Knowledge of Results on the Performanceof a Simple Vigilance Task," Journal of ExperimentalPsychology, 64 (1962), 58-61.
24. Smith, R. L., L. F. Lucaccini, and M. H. Epstein,"Effects of Monetary Rewards and Punishments onVigilance Performance," Journal of AppliedPsychology, 51 (1967) , 411-416.
25. Sternberg, S., "Two Operations in Character Recognition:Some Evidence from Reaction-Time Measurements,"Perception and Psychophysics, 2 (1967), 45-53.
26. Stone, M., "Models for Choice-Reaction Time,"Psychometrika, 25 (1960), 251-260.
27. Teichner, W. H., "Recent Studies of Simple Reaction Time,"Psychological Bulletin, 51 (1954), 128-149.
28. , and M. J. Krebs, "Laws of VisualChoice Reaction Time," Psychological Review, 81(1974), 75-98.
29. Weidenfeller, E. W., R. A. Baker, and J. R. Ware, "TheEffects of Knowledge of Results (True and False) onVigilance Performance," Perceptual and Motor Skills,14 (1962), 211-215.
30. Woodworth, R. S., and H. Schlosberg, ExperimentalPsychology, New York, Holt, 1958.
CHAPTER V
SUMMARY AND CONCLUSIONS
The present study was designed to determine the relative
effects of monetary reward and knowledge of results of per-
formance on a complex-choice reaction time task. The investi-
gation covered twenty-six male and thirty-two female under-
graduate students enrolled at North Texas State University.
The mean age of the males .was 21.2 years and the mean age of
the females was 22.3 years.
The basic design was a three-dimensional analysis of
variance in which the three main factors and their respective
treatment categories were sex (male-female); motivation
(reward-knowledge of results-control); and, trial (twenty-one
individual or three blocks of seven each).
The complex-choice reaction time task consisted of a
visual choice reaction time apparatus that provided pre-
sentation of up to nine stimulus lights at any one time and
allowed independent selection of the eight response keys. Each
subject was presented twenty-one different trial problems in
identical sequence, with each of the seven possible responses
presented three times each. The subject was required to add
the number of lights presented, subtract that number from
a constant number and then press the correct answer on the
50
51
response key. The dependent variable consisted of the sub-
ject's reaction time to each of the twenty-one trials.
The reward condition subjects received twenty-five cents
for every response that was faster than a preestablished
criterion and twenty-five cents was deducted from their total
for every response slower than the same criterion. The know-
ledge of results of performance subjects were told their re-
action time after each trial. The control group received no
feedback at all.
The data obtained in this study appear to warrant the
following conclusions:
1. There were no significant differences between any
of the following motivational conditions: reward, knowledge of
results and control. A statistical analysis of the individual
subjects' reaction times yielded no significant differences
between any of the motivational conditions.
2. There was a significant overall practice effect in
this study. A statistical analysis of the subjects' reaction
times indicated that the subjects were reacting significantly
(.01 level) faster as the time on task increased.
3. There was a significant difference between sexes
with the reaction times for all motivational conditions
combined. A statistical analysis indicated that the males had
significantly (.01 level) faster mean reaction times than
the females.
52
4. A complex-choice reaction time study does not pro-
duce the typical results found in simple and simple-choice
reaction time studies. It should be emphasized that the re-
sults of this study indicate possible avenues for further
research in complex-choice reaction time experiments.
APPENDIX
TABLE VII
REWARD SUBJECTS' REACTION TIMES ON EACH TRIAL
Trial Subject3* 4* 5 6* 7 8 9 10*
1 2.46 1.87 1.64 1.99 2.33 3.90 1.20 2.80 1.95 4.862 2.60 1.47 1.64 1.57 2.07 2.48 1.04 9.64 1.37 2.063 3.96 2.83 2.23 1.80 2.54 2.67 1.24 6.05 1.74 2.214 2.03 1.71 2.01 2.34 1.79 4.48 3.06 2.20 2.36 5.805 1.35 2.25 4.14 7.07 4.61 9.99 1.53 7.55 4.54 3.466 1.34 1.77 1.29 1.85 2.06 2.18 1.24 2.22 1.71 2.677 1.09 1.25 1.60 1.30 1.51 1.70 1.11 1.73 1.33 1.858 1.39 5.99 5.01 2.50 2.70 2.99 1.25 4.09 1.21 2.509 0.86 1.62 1.10 6.40 1.54 2.97 1.18 1.77 1.65 2.1610 2.01 2.08 2.31 2.26 1.94 3.37 1.42 2.82 3.56 2.2211 1.36 1.25 1.05 1.71 1.44 1.18 0.87 1.52 1.27 1.5112 1.28 1.18 0.92 1.10 1.58 1.38 1.19 2.76 1.55 1.1513 1.28 1.94 1.16 1.22 1.51 1.78 1.05 9.99 1.55 1.7614 1.95 2.23 3.13 2.25 3.05 3.52 2.66 7.50 2.72 6.0715 1.38 1.86 4.76 1.98 2.69 2.57 1.47 2.01 4.81 4.0916 1.17 1.29 1.03 1.83 1.42 3.23 0.88 1.61 1.50 1.5617 2.20 1.48 3.01 1.73 2.07 2.11 1.33 3.66 2.09 2.7618 2.22 1.30 1.37 1.50 1.80 1.47 1.42 3.62 1.33 1.3819 0.79 1.26 0.91 1.18 1.25 1.44 0.96 1.94 1.15 1.5720 1.39 1.94 3.26 2.83 3.00 3.06 0.72 2.55 2.16 2.1521 2.49 1.31 1.22 1.37 1.86 2.11 1.28 1.75 1.53 1.64
*Female subjects.
53
54
TABLE VII --Continued
Trial Subject11 *2 _13*1 _ _4 -5 6 17* 18* 1
1 1.67 2.06 1.35 2.84 1.74 2.46 2.33 9.99 1.962 1.61 7.68 1.10 2.70 1.73 1.72 2.42 3.53 1.473 1.76 2.57 1.18 2.37 2.33 1.93 2.86 3.96 1.934 1.96 2.18 5.81 4.17 1.96 2.28 3.16 2.43 2.305 3.45 8.53 2.12 7.36 9.80 3.26 2.85 2.31 7.176 1.58 1.89 1.80 1.64 2.17 1.55 2.11 1.77 1.867 1.13 1.70 2.74 2.53 1.37 1.79 1.39 1.94 1.948 1.54 3.34 1.44 3.47 3.17 4.87 2.29 9.99 2.259 1.26 1.76 0.99 1.61 1.37 1.97 1.87 3.81 1.12
10 1.87 2.57 2.63 2.78 2.30 4.95 2.33 2.72 1.8711 1.24 1.44 1.04 1.12 1.58 1.24 2.24 2.06 1.2412 0.94 1.94 1.05 1.22 1.17 1.47 1.32 1.25 1.9013 1.18 1.77 1.31 1.99 1.19 4.32 1.56 2.16 1.3614 2.93 9.77 1.52 2.77 2.32 2.83 8.75 3.98 7.6415 9.69 2.16 1.72 3.91 2.44 2.44 2.65 2.90 1.9616 1.60 1.69 1.53 1.55 1.50 0.95 2.80 1.72 1.2817 1.91 2.18 3.02 2.15 1.97 3.07 7.01 9.99 2.7118 1.01 1.72 1.41 1.17 1.26 1.83 1.32 3.03 1.1219 2.38 1.61 0.92 1.11 1.53 1.77 2.48 1.52 1.2320 2.49 1.95 1.18 2.61 4.80 4.02 2.43 2.67 2.4121 1.48 4.31 1.06 4.81 2.59 1.43 2.36 5.87 1.43
55
TABLE VIII
KNOWLEDGE OF RESULTS SUBJECTS' REACTION TIMES ON EACH TRIAL
Trial Sube_1* 2131 4* J5-j 7* -i7-iw 10
123456789
101112131415161718192021
2.472.473.133.396.422.115.069.991.622.901.642.182.176.782.991.792.712.151.492.411.54
3.041.893.192.452.831.49!1.582.891.453.191.181.361.423.642.091.641.871.921.931.601.58
2.217.212.792.773.882.782.023.061.552.042.051 .341.252.132.391.432.021.521.326.771.72
1.729.992.011.969.991.762.267.351.681.891.231.621.452.212.831.552.021.301.393.161.63
2.271.611.662.713.011.471.361.221.142.090.920.890.942.002.020.811.231.010.910.991.57
2.842.132.962.926.421.861.713.621.292.711.201.311.582.732.591.522.491.641.169.991.671
1.521.171.671.942.261.221.979.991.401.490.911.071.061.941.881.004.491.161.332.501.301
2.962. 124.102.592.081.921.497.651.682.381.501.431.522.535.331.792.422.671 .225.181.70
5.751.595.002.955.051.811.302.401.912.442.341.331.572.372.171.972.091.591.181.531.431
*Female subjects.
2.111.585.922.732.111.821.362.051 .663.081.532.321.223.202.051.291.291.271.391.071.57
56
TABLE VIII --Continued
Trial Subject_ _ _ 12__ _1-3__ __14* 15 16* 17 18* 19 20
1 2.28 1.68 4.30 3.53 1.85 2.43 2.05 1.90 2.70 2.322 1.42 2.88 3.02 1.77 1.33 1.81 1.88 2.21 2.18 1.783 1.87 3.30 9.99 2.74 1.92 1.92 2.41 1.93 3.45 5.024 6.35 3.00 3.69 3.37 1.46 2.09 4.14 2.16 3.05 1.735 5.86 3.25 8.17 6.38 1.90 2.75 2.22 4.25 3.77 5.846 1.66 2.36 2.06 2.84 1.31 1.69 3.45 1.62 1.78 2.447 1.29 1.14 3.81 2.62 1.69 1.39 1.64 1.60 1.83 1.698 2.09 3.01 1.88 1.45 2.30 1.66 2.01 2.70 2.48 1.659 0.84 1.80 2.13 9.99 1.19 1.39 1.72 1.76 1.80 1.4210 3.02 3.25 3.32 5.20 1.19 1.99 2.16 2.36 1.69 2.0911 1.04 1.97 2.98 3.35 1.06 1.98 1.65 1.04 1.26 1.3612 1.13 1.52 2.35 1.53 1.05 0.99 1.27 1.59 1.53 1.1813 1.36 1.87 1.67 1.70 1.57 3.29 1.39 1.26 1.38 1.1814 1.69 4.10 2.83 2.85 0.92 6.92 4.08 1.95 4.10 0.9515 1.91 2.76 2.31 1.86 1.91 4.69 2.39 1.61 2.06 1.5016 1.07 1.98 2.18 1.96 0.95 1.47 2.04 1.90 1.80 1.6817 1.93 2.30 3.18 2.59 1.09 1.78 1.94 1.90 1.99 1.2118 1.02 1.92 2.48 5.66 1.10 1.21 1.69 1.29 1.20 1.1819 1.06 1.89 1.27 6.80 1.37 1.77 1.49 1.10 1.07 1.1720 1.76 1.98 2.11 3.64 1.30 1.44 2.93 2.90 1.91 1.4421 1.19 2.58 1.97 1.98 0.72 1.88 2.21 1.38 1.46 0.98
*Female subjects.
57
TABLE IX
CONTROL SUBJECTS' REACTION TIMES ON EACH TRIAL
Trial Subject1 2*13*1415* 6*17*8* 10
1.979.992.881.908.751.253.331.370.969.991.710.901.183.621.350.963.710.990.911.881.24
1.451.542.562.786.732.171.353.501.422.321.761.731.452.243.421.432.122.071.441.461.35
2.132.103.629.991.841.761.482.081.432.411.361.371.592.402.221.442.411.191.241.411.66
1.7611.7212.5612.5412.250.881.096.131.446.681.381.520.702.432.501.344.831.070.912.402.32
4I__ -__ __tI
*Female subjects.
1.862.592.112.754.631.651.302.631.241.831.241.332.749.993.131.191.831.281.233.701.35
3.792.021.711.919.991.131.333.391.233.060.761.051.041.472.250.741.641.290.921.001.03
2.351.642.832.591.307.342.031.711.442.381 .381.371.662.632.301.962.291.421.312.521.35
2.342.203.552.734.802.411.673.111.413.081.441.241.484.973.471.332.781.831 .402.081.95
2.351.921.562.672.291.371.331.271.161.581.051.051.150.965.861.221.131.260.961.461.49
IL -_ _ _ _..L . 1 1 -I .- -. -I1
123456789
101112131415161718192021
1.521.531.902.492.211.631.512.241.292.241.371.311.407.772.381.141.271.230.811.511.33
58
TABLE IX -- Continued
Trial Subject*12 3 4* 15* 16* 7 18 19
.123456789
101112131415161718192021
1,.90,1.832.413.093.443.132.043.882.521.932.18'1.431.872.292.181.832.571.731.712.012.10
3.241.842.602.052.911.481.652.571.322.572.201.200.972.163.381.072.531.3611.092.181.58
4.342.122.372.135.861.541.762.211.542.211.491.411.422.582.501.361.731.341.192.2612.141
7.332.202.742.651.922.502.132.131.562.121.461.511.642.501.711.352.081.421.312.371.49
2.441.343.502.091.542.081.312.072.811.811.371.0511.253.282.182.621.411.441.441.901.23
1.731.431.905.031.381.821.191.451.721.971.271.261.211.761.751 .731.331.361.371.401.43
2.491.761.601.682.571.49,1.2015.671 .401.841.041.071.102.053.081.231.951.461.151.961.20
5.472.071.722.675.543.121.831.712.212.735.231.351.622.482.29'2.492.221.322.013.161.47
2.881.432.144.272.060.891.422.151.261.841.221.471.362.522.661.284.021.421.551.451.68
- I- -
IIIf1
59
TABLE X
MEANS AND STANDARD DEVIATIONS OF MOTIVATIONAL CONDITIONAND TRIAL BLOCK REACTION TIMES
Motivational Statistic Trial Block Main Effect--Condition 1 2 3 Motivation
M 2.73 2.39 2.20 2.44Reward SD 0.84 0.80 0.63 0.78
N 19 19 19 57
M 2.82 2.24 2.00 2.35Knowledge SD 0.84 0.68 0.61 0.79
N 20 20 20 60
M 2.58 2.09 1.81 2.16Control SD 0.65 0.49 0.26 0.58
N 19 19 19 57
Main M 2.71 2.24 2.00 2.32Effect SD 0.77 0.67 0.55 0.73--Blocks N 58 58 58 174
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