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Furedy, J.J., and Champion, R.A. (1963). Cognitive and S-R interpretations of
incentive-motivational phenomena. American Journal of Psychology, 76, 616-623
COGNITIVE AND S-R INTERPRETATIONS OF INCENTIVEMOTIVATIONAL PHENOMENA
By J. J. F UREDY and R. A. C HAMPION ,
University of Sydney, Australia
Following Bitterman's delineation of opposing predictions derivable from the
theories of Spence and Tolman,1 Gonzalez and Diamond obtained experimental
results which were interpreted as putting the differences between the two
theories in clearer perspective.2 Their most striking finding concerned two
groups of rats given a series of unrewarded trials in a runway, Rx, which was
dissimilar to the empty end-box, By. In a second stage, the members of one of
these groups (Group B) were directly placed and fed in Bx, a box similar to Rx
but unlike By, while the other rats (Group C) were fed in By. It was deduced
that, in a third stage of further unrewarded trials in Rx By, Spence should
predict faster running in Group B than in Group C, whereas Tolman should
predict the opposite result; the data were in accordance with the prediction
attributed to Tolman. While, however, Bitterman's deductions follow directly
from Spence's theory as explicitly stated,3 there remains the possibility that
Spence did not refer to some factors which might also be taken into account in
any further test of S-R theory, and the following study was designed to allow
for the possible role of two such factors.
In outline, Spence has supposed that when a goal-object such as food leads to a goal
response (Rg) in the end-box of a runway, cues (S2) temporally contiguous with Ro
come to elicit some component (rg) of this response through classical conditioning; if
stimuli in the starting box and runway (S1) bear any similarity to S2, then they may
elicit rg anticipatorily through stimulus-generalization, so that the stimulus-properties
of rg (sg) become part of the complex of stimuli eliciting the instrumental response of
running. By assuming that the intensity of s0 varies with the frequency and vigor of Rg,
Spence has envisaged a mechanism mediating the known activating effects of foodreward. It is not a necessary feature of this model, however, that sg should come to
elicit the particular instrumental response under scrutiny by an experimenter, for if
some response other than running should be dominant in the runway-situation, then sg
could well come to form part of the complex eliciting this competing response and so
interfere with the response being
* Received for publication December 7, 1961.
M. E. Bitterman, Review of Spence's Behavior Theory and Conditioning, this JOURNAL,
70, 1957, 141-145, esp. 144.
2
R. C. Gonzalez and Leonard Diamond, A test of Spence's theory of incentive-motivation, this
JOURNAL, 73, 1960, 396-403.
3
K. W. Spence, Behavior Theory and Conditioning, 1956, 134-136.
1
INCENTIVE-MOTIVATIONAL PHENOMINA
617
measured. It is emphasized that, according .to this elaboration of Spence's hypothesis, it is not the hypothetical r g but some overt response which is
thought to compete with the instrumental response under study. The
experiment of Gonzalez and Diamond began with a series of unrewar ded trials
in a 48-in. runway, the running times being of the order of 40 sec, and these
times increased slightly over the first set of trials, suggesting that competing
responses were strong. This, therefore, was the first factor which the present
study sought to control, by the use of rewarded trials in the first stage so as to
ensure the clear dominance of the running response.
To make a complete application of Tolman's type of theory to the data of their
study, Gonzalez and Diamond extended the theory by supposing that directplacement feedings in Bx, for example, acted not only to increase the valence
of the stimuli in Bx as an end-box (S 2 ) but also the valence of the cues in Rx
(S 1 ), because of their similarity to S2. Thus the performance of Group B should
have been interfered with by direct feedings in Bx because of the similarity of
Bx to Rx and the dissimilarity of Bx to By, making the valence of the stimuli in
By (S 2 ) relatively less than that of the stimuli in Rx (Si). It can be shown, on the
other hand, that S-R theory leads to such an expectation without any extension.
According to Spence's hypothesis, the direct-placement feedings in Bx or By cause
rg to be elicited by the stimuli there (S'2) so that, other things being equal, rg
should occur more strongly in Rx with feedings in Bx because of the greater
similarity between Bx and Rx than between By and Rx. But again the model does
not require that only rg is conditionable to S'2, and it must be recognized that under
the somewhat unusual direct-placement conditions the cues in Bx and By may
come to elicit a variety of other overt responses which might be loosely
characterized as 'looking for food/ that these will transfer to Rx more from Bx
than from By, and that performance could well be inferior in Group B for this
reason. This transfer could also occur under normal runway-training conditions,
as Hull envisaged, 4 but the competing responses are assumed to become
subordinate to the reinforced instrumental response of running. The r g , on the
other hand, is also transferred, but is thought of as incapable of competing with
any overt response. To make some allowance for this second factor which
emerged from a more detailed consideration of S -R theory, an attempt was
made to reduce competing, overt ('looking-for-food') responses to a minimum by
sounding a tone whenever 5 entered a goal-box containing food (Bx or By), this
stimulus not being presented while 5 was in Rx. In Skinner's terms, it was
intended that the tone should become a discriminative stimulus for food. The
use of this stimulus should not have destroyed the rationale of the experiment,
the similarity between Bx and Rx still being greater than that between By and
Rx (Spence), with the relative valence of By still greater than that of Bx
(Tolman).
Method: ( 1 ) Subjects. The Ss were 16 experimentally naive male albino rats,
ranging in age from 83 to 107 days at the beginning of preliminary training.
(2) Apparatus. The apparatus was similar in function to that used by
Gonzalez and Diamond, but it differed in structural detail. There were two
runways, 5 in. wide, 24 in. long, and 5 1 / 2 in. high. One runway had white
walls and a wire4
C L. Hull, A Behavior System, 1952, 124-125.
618
FUREDY AND CHAMPION
covered aluminum floor, while the second runway had black wails and an uncovered floor. There were also four boxes, 5 X 6 l/ 2 X 5 l / 2 in., which could be
used interchangeably as starting boxes or end-boxes, two similar to the white runway and two similar to the black runway. Another set of four boxes, identical
with the first set except for their greater length of 9l/2 in., was used in the second
replication because the Ss were older and larger. The runways and boxes were
covered with clear perspex. The boxes were separated from the runways by means of
transparent guillotine-doors, while the interior of each goal-box was hidden from
the runway by an opaque curtain on the runway-side of each door. When E lifted
the door between the starting box and the runway a micro-switch was automatically
closed so as to start an electronic chronoscope, and the passage of the rat's body across
a gap in the metal floor between starting box and runway activated a relay which
stopped the chronoscope, thus giving a measure of starting time. Running times
were measured less precisely, with a stopwatch. Another microswitch was linked
with the door between the runway and the goal-box, so that when E closed this
door as S entered the goal-box, a 500-cpsec. 85-db (spl) tone was sounded for 5
sec.
(3) Procedure. The experiment was conducted in two replications, with 6 Ss
in the first and 10 Ss in the second.
(4) Preliminary training. For the first 10 days the Ss were put on a 24-hr,
feeding schedule, handled for 5 min. daily, and allowed to eat for 1 hr. On the
eighth day the food was changed from dry pellets to wet mash. An equal number
of Ss was assigned to the white and black runways, and they were allowed to explore
the apparatus with the doors open, no food-reward, and with no tone, for 5
min. daily until all Ss were readily crossing into the goal-box through the curtain.
This pretraining was conducted immediately prior to the daily eating session; it
took three days for the first replication and six days for the second replication.
Stage 1. After at least 2 min. of adaptation in the experimental room, each S
was given training trials in the appropriate runway, as follows. When S oriented
towards the door of the starting-box, the door was opened by E and then lowered
after S had passed into the runway, so as to prevent retracing. When S passed
through the curtain into the goal-box, the second door was lowered, to prevent
retracing, and the tone sounded for 5 sec. The reward for each trial was approximately 2 gm. of wet mash, half food and half water by weight. As soon as S
finished eating (after approximately 1 min.), it was replaced in the starting box
for the next trial. The Ss were given 4 trials on each of two days, being allowed to
eat wet mash ad lib for 30 min., starting at least 30 min. after the 4th trial each
day.
Stage 2. On the basis of mean starting times over the last 4 trials of Stage 1,
the two main Groups B and C were established by matching the Ss in pairs, with
the restriction that half the Ss in each group be trained in the white and half in the
black runway. Then the Ss were given direct-placement feedings, either in a box
similar to the starting box and runway of Stage 1 (Bx, Group B) or in the goal-box
of Stage 1 (By, Group C). After 3 min. of adaptation in the experimental room each
S was placed directly into the box containing approximately 4 gm. of wet mash
(50% dry food by weight) and the tone was sounded for 5 sec. As soon as 5
had finished eating, it was returned to the holding cage for 1 min. and
INCENTIVE-MOTIVATIONAL PHENOMINA
619
then replaced in the box for a further period of eating. The Ss were fed four
times on each of four days in this fashion, and once on the fifth day. On the first
four days the Ss were allowed to eat mash ad lib for 30 min., beginning at least
30 min. after the last direct-placement feeding, but on the fifth day the single
feeding in the box was followed by the first four trials of Stage 3. By making
small adjustments in the amount of mash presented in the box over the 17 trials
of Stage 2, it was ensured that the average time spent in eating in the goal box
per trial by each S was approximately 120 sec. (ranging from 117 to 126 sec.) and
that the average times for Groups B and C were equal at 120.7 sec. As al ready
noted, care was also taken to see that the entire time in the goal -box was spent in
eating, in both Stage 1 and Stage 2.
Stage 3. After the direct-placement feeding on the fifth day of Stage 2, all Ss
were removed from the experimental room. At least 15 min. later they were re turned to the room, allowed 2 min. of adaptation, and then given 4 trials in the
manner of Stage 1. A further 4 trials were given on the next day.
F IG. l. PERFORMANCE IN THE SECOND HALF OF S TAGE l AND IN S TAGE 3
Results. The performance of the two Groups B and C on the last 4 trials of
Stage 1 and the 8 trials of Stage 3 is plotted in Fig. 1, in terms of mean startingtime. The running times showed the same trends as a measure of performance,
but were more variable than the starting-times. Taking the first block of two
trials in Stage 3 as a measure of the effects of Stage 2, the individual mean
starting-times (sec.) were as follows. Group B: 4.00, 2.50, 1.95, 1.80, 1.65,
1.60, 1.60, and 1.45; Group C:
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FUREDY AND CHAMPION
0.85, 0.75, 0.70, 0.65, 0.60, 0.58, 0.50, and 0.50. Since there was no
overlap in these two samples, no statistical test was deemed necessary, the
performance of Group C being clearly superior. It may be observed in Fig. 1,
however, that the difference between the two groups had all but disappeared by
the second block of two trials in Stage 3.
Discussion. The chief impression provided by the data of this experiment is
that of further support for Tolman's position, in view of the clear superiority of
Group C in the early trials of Stage 3. It is generally accepted, however, that a
theory is rarely demolished by the results of a single experiment, as a crucial
instance, but rather tends to give way gradually to a superior theory. Since S-R
theory appears to offer the most potent alternative to a cognitive interpretation
of the data, the remainder of this discussion is devoted to the chief comments
still open to the S-R theorist and to possible defects in the present study.
It will be recalled that the experiment was designed to ensure: first, that the
instrumental response of running was dominant at the end of Stage 1, so that
further increase in the strength of rg in Stage 2 would not activate some
competing response; and secondly, that 'looking-for-food' responses generated
in Stage 2 would not transfer to the starting box and so constitute another form
of competition with running as measured in Stage 3. Whereas the first of these
aims was easily achieved, it is felt that some doubts must be held about the
effectiveness of the tone as a discriminative stimulus. Indeed, the search for an
effective means of preventing the generation of competing responses in Stage 2
leads the S-R theorist to a dilemma. If the feeding-box stimuli (S'2) of Stage 2
and the stimuli of starting box and runway (S1) are made identical, then
although rg may be strengthened in the former and transferred to the latter
situation, competing responses may also be transferred, being made all the
stronger by the dynamogenic effects of rg. If S1 and S2 are made quite dissimilar
on the other hand, then not only the undesirable competing responses but also
the activating rg may fail to transfer. In the present experiment a compromise
was sought by presenting the tone in S'2 (feeding box) and S2 (goal-box) only
for the first 5 sec., while the animal was moving towards food, and by not
sounding the tone for any length of time during actual eating, when rg was
presumably occurring. If this technique failed in its purpose, however, then the
performance of Group B would have been depressed in comparison with that of
Group C, because of the greater similarity of Rx to Bx than to By, and this was
the obtained result
In examining the results of the present study, attention was concentrated upon the
comparison of Groups B and C within Stage 3. This was done in the belief that
INCENTIVE-MOTIVATIONAL PHENOMINA
621
comparisons between levels of performance at different stages have no relevance to the
comparison of the theories of Tolman and Spence. It might be suggested that some
meaning could be given to between-stage comparisons by the use of a control group of
Ss given no direct-placement feedings in Stage 2 but simply held in their home cages
and given normal daily feedings. The irrelevance of between-stage comparisons and
the ineffectiveness of this control group may be demonstrated by consideration of the
following possibilities in terms of Fig. 1. First, taking the data at face-value, the
performance of Group C was relatively unaffected by the events of Stage 2 whereas
that of Group B was considerably impaired. The comparable result for Group C in the
study of Gonzalez and Diamond was a marked increase in response strength, and the
failure to obtain such an effect in the present case may have been due to the use of
reinforced trials in Stage 1, which alone could have brought performance near a
maximum. It is not usual for 8 trials to suffice for this purpose in runway-training, but
further evidence for the possibility is to be found in the fact that Group C showed no
further improvement in the course of Stage 3. As far as Group B is concerned, the
modified cognitive theory would account for the decrease in response-strength by
reference to the superior valence of the runway (Rx) relative to the goal-box (By) as a
result of feedings in a box similar to the runway (Bx) in Stage 2. An S-R theorist, on
the other hand, could suggest that the tone failed to act as a discriminative stimulus, so
that the direct-placement feedings in Bx simply led to the occurrence of competing
responses in Rx in Stage 3. It could even be suggested that the use of the tone was illadvised in that, as a result of differential conditioning, it prevented transfer of rg to the
starting box and runway by its absence there. The answer to this claim, however,
would seem to lie in the substantial improvement in performance which occurred in
Stage 1, under conditions where the tone was present briefly in the goal-box but never
in the runway.
Instead of taking the data at face-value, it might be allowed that some forgetting
would occur in a group which did not have any direct feedings in Stage 2, enough to
locate such a control group somewhere between Groups B and C at the beginning of
Stage 3. If this were the case, the cognitive and S-R theories would seem to apply
equally well to the data, for both could predict improvement in Group C and
impairment of performance in Group B as a result of the direct-placement feedings.
Assuming that the position of the cognitive theorist has already been made clear, the
reason for such an expectation on the part of the S-R theorist may need elaboration. If
the reinforced trials of Stage 1 are to have any effect then it must be through the Rg-Sg,
mechanism as outlined above; i.e. the rg comes to occur anticipatorily in Rx through
stimulus-generalization from By, for although Rx and By differ in important respects
they still bear some degree of similarity to each other. This being so, direct feedings in
By should lead to some further improvement in performance in Stage 3, provided that
performance has not already reached a maximum by the end of Stage 1 or allowing
that some forgetting would have occurred otherwise, after the end of Stage 1. It is to be
presumed that the feedings in By would not cause competing responses in Rx, for
otherwise the learning in Stage 1 would not occur so readily. In the case of Group B,
on the other hand, the S-R theorist may argue as for the face-value case.
If this line of argument were followed to the limit it is conceivable that a control
group denied feedings in Stage 2 could deteriorate in performance to the same ex-
622
FUREDY AND CHAMPION
tent as Group B did in the present study (Fig. 1). Under these conditions it would be
concluded that the interpolated feedings in Bx had no effect, whereas feedings in By
led to considerable improvement in Group C, as found by Gonzalez and Diamond.
Even so, the S-R theorist could suggest that feedings in Bx produced opposed factors
which counter balanced each other in Group B, while the activating effects of rg were
free to show in the performance of Group C. It should be emphasized at this point that
Spence's statement of his version of the S-R position does not explicitly refer to these
theory-saving possibilities, and that the critics of this position have proceeded along
perfectly proper lines in their interpretations of the theory as stated. Nevertheless, it is
felt that an objective assessment of the position should exhaust every possibility.
In the light of these comments arising from a consideration of the present
data, some general findings and interpretations of Gonzalez and Diamond may
be reexamined briefly. These Es have suggested that, according to S-R theory,
the performance of groups fed in a box (Bx) similar to the starting box and
runway (Rx) (their Groups A and B) should be superior to that of groups fed in
a box (By) dissimilar to the rest of the alley (their Groups C and D). Now
whereas this type of interpretation may be applicable to the usual runwaytraining situation, in a comparison of groups trained with Rx Bx and Rx By, it
may be rendered invalid in the less usual, direct-placement situation by the
generation of competing ('looking-for-food') responses in Rx with placements
in Bx. Although this possibility was not allowed for by Spence in his brief
outline of an experiment,5 and not recognized at the outset by Stein when he
conducted the experiment,6 it need not be precluded from serious consideration.
A second implication of S-R theory for Gonzalez and Diamond was its failure
to account for effects obtained with variations in the similarity of feeding box
(S'2) to goal-box (S2) with the relationship of S'2 to starting box and runway (S1)
held constant. It is suggested, however, that their experiment has not produced
clear evidence of the existence of such effects, in the form of statistically
significant differences in Stage 3 between Groups A and B, and between
Groups C and D. Finally, it bears repetition that the cognitive interpretation
derived from Tolman completely encompasses all the findings.
SUMMARY
An experiment was conducted which sought to check the results of two groups used in an
earlier study of Gonzalez and Diamond. These were
5
Spence, op. cit., 147-148.
.
6
Larry Stein, The classical conditioning of the consummatory response as a de terminant
of instrumental performance, J. comp. Pbysiol. Psychol., 50, 1957, 269-278.
INCENTIVE-MOTIVATIONAL PHENOMINA
623
groups given a preliminary test without reinforcement in straight-alley
apparatus with a goal box (By) dissimilar to the starting box and runway (Rx)
and then given direct-placement feedings in a box (Bx) similar to Rx (Group B)
or in By (Group C). The reason for this replication was the attempt to allow for
the possible non-dominance of the instrumental, running response and for
competing responses generated in the direct feedings in Bx and generalizing to
Rx in a later test. Allowance was made for these factors by using reinforced
trials before the direct feedings and by sounding a tone with all entries into Bx
or By, as a discriminative stimulus for food. The result (Group C superior to
Group B) was in keeping with a cognitive interpretation of the phenomena
(Tolman), as proposed by Gonzalez and Diamond, but further features of an SR interpretation (Spence) were considered and not excluded.