Download Processes of fear-reduction in systematic desensitization: Cognitive

Reprinted from BEHAVIOR THERAPY, Vol. 4, No. 1, January 1973
Copyright ©1973 Academic Press, Inc. Printed in U.S.A.
Processes of Fear-Reduction in Systematic Desensitization:
Cognitive and Social Reinforcement Factors in Humans'
DAVISON GERALD C.
State University of
New
York at Stony Brook
AND
C. TERENCE WILSON
Rutgers University
Systematic desensitization (SD) is a technique which usually takes place
in a social context and involves the use of imagery and possibly other
symbolic/cognitive processes as well. Research and theory bearing on these
two sets of uniquely human variables arc critically reviewed. The main
conclusions are as follows: (a) a conceptualization of SD as a procedure
which is effective via the induction of counterphobic cognitions has failed
to find replicable support and is, furthermore, questionable on a priori
grounds because of the doubtful relevance of attribution theory to the
alteration of severe, long-standing phobias; (b) expectation of gain can
produce increments in beneficial effects arising from SD but does not appear
to account for all improvement; (c) deliberately induced self-instructions
may increase the efficacy of SD and may, furthermore, be operating in
uncontrolled but important ways in the procedure as currently practiced;
(d) the word "cognitive" is used in both a descriptive and an explanatory
sense in the literature, threatening even more obfuscation than already
exists; (e) experiments designed to determine the role of the desensitizer
as a social reinforcer for increased (imaginal) approach behavior are either
inappropriate in conception, confounded in design, or productive of inconclusive results; and (f) stimulus–response formulations are proposed not
to be ipso facto incapable of usefully conceptualizing and manipulating
covert processes, including imagery.
Although a substantial amount of both clinical and experimental evidence currently attests to the efficacy of systematic desensitization (SD)
' Preparation of this paper was facilitated by support from Grant MH 145.57-03
from the National Institute of Mental Health to Gerald C. Davison, and by Rutgers
Research Council and Biomedical Science Support Grant to G. Terence Wilson. We
extend thanks to Steven 'I'. Fishman for his critical reading of an earlier draft of this
paper.
Requests for reprints should he sent to Gerald C. Davison, Department of
Psychology, State University of New York, Stony Brook, NY 11790.
1
Copyright © 197:3 by Academic Press. Inc.
All rights of reproduction in any form reserved.
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DAVISON AND WILSON
in reducing neurotic anxiety (Bandura, 1969; Marks, 1969), debate as
to the effective process mechanisms continues. The delineation of the
critical variables operating in successful SD would contribute greatly
to our understanding of behavior change processes in general and would
allow for the development of more refined, efficient therapeutic methods
for reducing neurotic fears. Previous reviews of the literature have dealt
with human process studies in SD in general (Bandura, 1969; Lang,
1969), while Wilson & Davison (1971) have recently discussed the
relevant animal analogue research. In the main, all these reviews have
tended to concentrate on various conditioning formulations which have
been proposed to explain SD. In this paper we shall focus specifically
on more recent, peculiarly human avenues of theory and research in SD,
viz., the role of social and cognitive factors.
COGNITIVE FACTORS IN DESENSITIZATION
The general proposition that systematic desensitization might usefully
be construed in terms of cognitive processes was originally enunciated
by London (1964). Ile proposed that SD derived its effectiveness
through the modification of a person 's thinking and expectancies about
the feared situation/object. Experimental research along cognitive lines
actually began with the investigations of Valins (1966; Valins & Ray,
1967) within the social psychological framework of attribution theory.
False Feedback of Responsiveness
Valins' interpretation of SD derived from Schachter 's (1964) theory of
emotional behavior, which holds that emotion is the conjoint product of
both physiological arousal and cognitive/ perceptual factors. According
to this formulation, physiological arousal provides a nonspecific basis
of emotion; the quality of emotion the individual experiences is said to
be a function of how he explains to himself the reasons for the arousal
(cf., Schachter & Singer, 1962). Valins extended this position by sugfor gesting that actual autonomic arousal might be unnecessary in order
emotional reactions to be influenced provided that the individual only
believe he is aroused or not even if this is not the case. Accordingly,
Valins reasoned that Ss might be induced to believe that they were
reacting nonfearfully in the presence of the phobic stimulus and thereby
relabel that stimulus as nonthreatening and subsequently behave less
fearfully.
Valins and Ray (1967) investigated this possibility in two closely
related studies. Unselected Ss (study I) and Ss who had earlier indicated
fear of snakes on a questionnaire (study II) were recruited for a study
investigating physiological reactions to frightening stimuli. Ten slides
FEAR DEDUCTION IN SD
3
aof
versin snakes (study I) in order of previously ranked increasing
were presented interspersed with slides of the word SHOCK (which
were followed by an uncomfortable though not painful shock); in
study II the snake stimuli entailed exposure to a live snake in a cage
behind a one-way screen. Experimental Ss heard what they were erroneously led to believe was their heart reacting noticeably to the shock
slides but not to the snake presentations. Control Ss heard the same
sounds but were told they were extraneous noise. In both studies experimental Ss showed a greater amount of posttreatment approach behavior
towards the snake than did the control Ss, a finding which Valins and
Ray construed as confirmation of their hypothesis. They suggested that
this false feedback acted in a manner analogous to the role of relaxation
in SD, which, they proposed, might derive its effectiveness by inducing
the cognition that the previously fear-eliciting stimulus no longer retained its aversive properties.
This novel interpretation of SD has attracted considerable attention
as an alternative to more conventional conditioning accounts. In an
unwarranted overgeneralization, Murray and Jacobson (1971) state that
this study strongly demonstrates " that the critical factor in desensitization
therapy is a change in belief about the self—similar to that occurring in
traditional therapy—rather than the mechanics of relaxation, hierarchies,
i mages, and so on" (p. 739). Valins and Ray more properly point out
that "it is not possible to conclude that successful desensitization
"
therapy is based upon the induction of these cognitions, but they do
conclude that "cognitions about internal reactions are important modifiers of behaviors," and suggest that the kind of cognitions produced by
the false feedback might be responsible for successful desensitization.
in view of the significance attributed to the Valins and Ray report, it
is unfortunate that several factors preclude an unequivocal interpretation of the findings. In study I, Valins and Ray had to perform an
internal analysis on the data, discarding subjects who reported previously touching a snake, in order to demonstrate a significant experimental effect. This confounds the cognitive manipulation with selection
factors. In study II significant treatment effects were observed, but on
the basis of the amount of money required to induce subjects to touch
the snake rather than the conventional behavioral avoidance test utilized in other studies of SD and rejected by Valins and Ray because it
"
might have been "too frightening. The Valins and Ray dependent
measure represents a relatively weak behavioral requirement (Bandura,
1969), which makes it difficult to compare these data to other studies
on fear reduction methods.
r
Furthermore, several experiments have attempted in vain to confi m
4
FEAR REDUCTION
DAVISON AND WILSON
these results. Kent, Wilson , and Nelson (1972) followed precisely the
same false feedback procedure as Valins and Ray, with the substitution
of a standard behavioral snake-avoidance test to assess experimental
effects more stringently. Contrary to the original data they found no
behavioral or attitudinal effect of the false heartrate feedback. Sushinsky
and Bootzin (1970) reported a "conceptual replication " of the Valins
and Ray study in which they likewise failed to demonstrate an attribution effect on avoidance behavior. Those investigators eliminated the use
of shock which was employed as a contrast stimulus by Valins and Ray,
and instead provided subjects with feedback that their heartrate was increasing when slides of rats were projected, but not when slides of snakes
were shown. A number of procedural differences between this study and
the Valins and Ray experiments, such as the use of a pretest, could have
accounted for the differences in results. Sushinsky and Bootzin selected
Ss on the basis of a pretreatment behavioral avoidance test which
eliminated about 40% of those Ss who had reported fear on the screening
questionnaire (a typical finding in fear assessment; cf., Bernstein & Paul,
1971). Since the Valins and Ray Ss were either unselected or else chosen
on the basis of their self-report of fear, they were no doubt less fearful
than Sushinsky and Bootzin 's Ss. This issue is important since it does not
seem likely that the extremely fearful S, especially the kind of client
typically seen in therapy, can be deceived into believing that he is not
acting fearfully on exposure to an aversive object or situation with which
he has had considerable experience, a caveat issued by attribution theorists themselves, viz., "Since we would not expect that an individual
undergoing extreme pain, fear, or rage could easily be persuaded to
attribute the accompanying physiological arousal to an artificial source,
there should he limits placed on the generality of these notions"
( Nisbett & Schachter, 1966, p. 228).
Rosen et al. (1972) selected snake-fearful Ss on the basis of a behavioral
avoidance test, and additionally determined that these Ss associated an
increase in their heart rate with exposure to snakes, a neglected consideration in the aforementioned studies. In addition to the two groups
used by Valins and Ray, Rosen included two extra control groups. In
order to control for attentional effects one group heard their heartrate
increase to the shocks but not to the snake slides, while the other constituted a no-treatment control. Veridical heartrate measures were
monitored throughout the study in order to ascertain whether false
heartrate feedback brought about an actual decrease in physiological
arousal. Consistent with previous findings, the results revealed no significant differences between any of the groups on either behavioral or
questionnaire measures of fear. Nor did the false feedback serve to re -
I N SD
duce actual heartrate measures. Had Rosen replicated the Valins–Ray
false feedback effect while at the same time finding that such false feedback led to an actual reduction in heartrate, the original Valins–Ray
findings would have been open to a compelling alternative explanation
along conditioning lines, with the false feedback becoming a technically
expeditious though conceptually uninteresting procedure for inducing
a state (response) of nonanxiety which could, along counterconditioning
lines, neutralize anxiety to the snake stimuli.
Posttreatment interviews revealed that a critical assumption of the
Valins model had not been met, viz., Ss did not reevaluate their fear of
snakes despite the fact that they had accepted the feedback as their
own veridical arousal. Rather, they adopted an alternative explanation
of their heartrate reactions which allowed them to maintain their fear of
snakes: they decided that it was slides of snakes they were unafraid of;
not actual snakes. Consequently Rosen concluded that the methodology
employed by Valins and Ray is inappropriate to testing their assumption
that a cognitively induced reevaluation of fear will mediate changes in
avoidance behavior. On the other hand, it will be recalled that Kent
et aI. (1972) found that Ss did report reevaluating their fear, though,
as already stated, without any subsequent effect on avoidance behavior.
In another extension of the Valins and Ray (1967) paradigm utilizing
concurrent physiological recording Gaupp, Stern, and Galbraith (1972)
found no differential treatment effects on either behavioral avoidance or
self-report of fear across groups modeled after the two Valins and Ray
conditions and one in which subjects were given veridical physiological
feedback. Unlike Rosen et al. (1972) study, all three experimental groups
showed reduced physiological responding to the snake stimuli and
showed significantly greater improvement than a no-treatment control
group. Gaupp et al. (1972) interpret these data as challenging the
Valins and Ray cognitive hypothesis and supporting a conditioning
explanation of SD. Stern, Botto, and Herrick (1972) adduce further
evidence against the Valins (1966) attribution hypothesis by showing
that the behavior change Valins ascribed to the mere belief that physiological arousal was occurring may have been due to real physiological
changes.
Expectancy of Gain
Marcia, Rubin, and Efran (1969) have argued that expectancy change,
rather than any conditioning process, is the effective element in SD.
Snake-fearful Ss were administered a procedure in which Ss received
periodic mild shocks while watching what they were informed were
subliminal tachistoscopic presentations of snake slides. The high ex-
7
DAVISON AND WILSON
FEAR REDUCTION I N SD
pectancy subjects were told they were receiving an effective treatment
and were also shown bogus polygraph records indicating that their fear
reactions to the snake stimuli had decreased. Low expectancy Ss were told
that they were receiving an ineffective treatment and were given no
information about their physiological reactions. These two groups were
compared to a no-treatment control group and what the authors referred to as a SD condition. Marcia et al. interpreted their data as showing that the high-expectancy treatment produced the greatest reduction
in behavioral avoidance, and they concluded that change of expectancy
is the operative factor in SD.
However, this study has been strongly criticized by Bandura (1969),
Howlett and Nawas (1971), and Rimm (1970), among others, who
point out, for example, that various treatments were conducted in different years; that there was a differential rate of S-attrition across groups
which confounds any comparisons made between the groups; that the
assignment of Ss to groups was questionable; that the "desensitization "
group in the study was quite different from SD; and that a full analysis
of the data, which shows that high- and low-expectancy Ss did not in
fact differ from each other on behavioral avoidance, contradicts the
authors' conclusions!
Several studies suggest that processes other than general expectancy
of therapeutic gain are operative in effective SD (e.g., Davison, 1968;
Lang, Lazovik, & Reynolds, 1965; Paul, 1966). Fishman (1970) found
that SD with powerful suggestions of the therapeutic efficacy of SD
combined with exposure to false physiological feedback via oscilloscopic
display supposedly indicating decreased reactivity did not enhance the
effect of SD administered without such suggestions. Similarly, Lomont
and Brock (1971), McGlynn and Williams (1970), McGlynn and Mapp
(1970), and McGlynn (1971) have shown that specific pretreatment
instructions designed to inculcate either positive or negative expectations
about therapeutic outcome have exerted no influence on the outcome of
treatment. Fishman ' s study is noteworthy also for highlighting an important methodological point in that he ascertained that his expectancy
manipulation was successful in creating differential expectations across
groups during SD treatment even though it failed to influence outcome.
Independent assessment of the expectancy or placebo value generated
by different treatments should be standard practice in therapy outcome
studies. For example, merely labeling a procedure a placebo treatment
because it does not seem, on rational grounds, to include any "active
'
ingredients," does not ensure that its capacity to mobilize Ss expectations of benefit will be equal to that of the other treatments employed
in the study.
In contrast to the above results, other studies have indicated that
therapeutically oriented instructions can significantly influence the
efficacy of SD ( Borkovec, 1972; Leitenberg, Agras, Barlow, & Oliveau,
1969; McGlynn, Reynolds, & Linder, 1971; Oliveau, Agras, Leitenberg,
Moore, & Wright, 1969). Indeed, it was only with these instructions
that SD was found to significantly decrease avoidance behavior relative
to control groups. However, it should be noted that neither Borkovec
(1972) nor McGlynn et al. (1971) found a significant difference between SD with and without therapeutic instructions, and while both
Leitenberg et al. (1969) and Oliveau et at. (1969) did show this difference, they also found that within-subject analyses of the SD group
without instructions "support the hypothesis that the procedure of SD
alone produces some therapeutic effect" (Oliveau et at., 1969, p. 32).
McGlynn et al. (1971) suggest that experimenter bias might explain
the latter findings since the experimenter in those studies administered
both the instructions and the respective treatments. Woy & Efran (1972)
compared SD groups with and without positive expectations of successful therapeutic outcome in a study on public speaking anxiety, modeled
after Paul (1966), in which the therapists were `blind ' as to the expectancy manipulation employed. Results showed that the high expectancy
SD group differed from the neutral expectancy group only on one out
"
of six dependent measures, a "self perception of improvement rating on
a seven point scale, but not on any of the measures used by Paul (1966).
Furthermore, both SD groups improved significantly more than the no
treatment control group on several measures. This well-executed study
strongly supports the contention that the SD procedure is effective
independent of any expectancy factors (Davison & Wilson, 1972).
6
Feedback of Progress
Wilkins (1971) has stated that the efficacy of SD is attributable
partly to cognitive factors such as expectancy of improvement, as dis"
cussed above, and what he terms " information feedback of success.
'
'
Extrapolating from Ben s (1967) theory, Wilkins suggests that S s perception of his own behavior during SD is a source of relevant feedback.
Thus, as he observes himself not signalling anxiety, the subject makes
the inference that he is not afraid. However , whether or not S signals
would seem to be under the control of the therapist ' s instructions to
introspect on whether or not he is anxious. Under these circumstances,
where the signalling is a function of instructions and the presumed detection of internal states, it is difficult to sec how S could be utilizing his
signalling behavior as the basis of an inference of whether he is anxious
or not.
DAVISON AND WILSON
FEAR REDUCTION IN SD
Progress up the hierarchy in SD is proposed by Wilkins as another
information feedback parameter causing S to cognitively reevaluate his
fear. In support of this argument he cites studies by Davison (1968),
Cooke (1968), and Lang et al. (1965), which found that the greater the
number of hierarchy items S had been desensitized to, the greater was
the posttreatment improvement. However, this finding is predicted by
the conditioning formulation (Wilson, in press, b ) and was interpreted
accordingly by the original investigators.
Two studies have tested this hypothesis by using bogus feedback of
progress up the hierarchy, analogous to the manner in which Valins
and Ray attempted to pit their cognitive interpretation of SD against a
conditioning one. Brown (1970) selected spider-fearful subjects who
were trained in muscle relaxation and then shown either slides of spiders
which they had carefully ranked in terms of aversiveness on a previous
occasion, or blank slides on which they were led to believe that spiders
were presented tachistoscopically at speeds too fast for conscious perception. Ss in the SD group (real slides, relaxation) were encouraged to
recognize that their progress up the hierarchy meant that they were
reducing their fear. Three other groups were yoked to this (SD) group
so that they received the same number of exposures to the various
hierarchy items for equal amounts of time. One of these groups, the
relaxation control group (blank slides, relaxation), was told that their
rate of progress was contingent on their autonomic activity, which was
supposedly being monitored. The other two groups, the expectancy control (real slides, relaxation), and the placebo control (blank slides,
relaxation), were informed that their rate of progress through the hierarchy was random and had been determined in advance.
Results of the posttreatment behavioral avoidance task revealed significant main effects for the expectancy and real slide manipulations
with no significant interactions. No differences on self-report of fear
emerged. Brown concluded that expectancy is a necessary but not sufficient component of effective SD. Unequivocal interpretation of these
data is impossible, however, in that the yoking procedure employed
necessarily confounds the design. Ss in the SD group exercised voluntary control in pacing their own progress through the hierarchy, which
was, by contrast, forced and involuntary in the other three groups, a
shown to influence behavior (cf., Geer,
difference which has been
'
Davison, & Gatchel, 1970). Wilson (in press, a) replicated Brown s
(1970) study and eliminated the confound by using preprogrammed
progression up the hierarchy. Results revealed that bogus feedback of
progress up the hierarchy had no effect on avoidance behavior although
it did significantly reduce self-report of fear. Contrary to Marcia et al. ' s
(1969) expectancy change interpretation of SD, exposure to real slides
of the snake proved to be a necessary condition for the reduction of
avoidance behavior despite the fact that an independent assessment indicated that there were no differences in the subjects ' expectations of
therapeutic gain across the different groups.
It is noteworthy that Brown (1970), like Marcia et al. (1.969) and
Valins and Ray (1967), reported a reduction in avoidance behavior
following cognitive treatments, but observed no differences in self-report
measures of fear. (Leitenberg et al. and Oliveau et al. report only behavioral data.) This finding is surprising in the present context, because
if behavior change is said to be mediated by a cognitive reappraisal of
the fear-eliciting stimulus, e.g., "Snakes no longer affect me as I thought
they would, " then one should logically expect self-report to reflect these
very salient cognitions. This seeming inconsistency has not been accounted for by the protagonists of cognitive conceptualizations.
8
9
Iinstruco Self -
Bandura (1969) and Lang (1968) have noted that the stimulus determinants of fear are not necessarily confined to internal visceral or
external cues, but might well include covert, self-generated stimuli
which probably interact with the former in controlling the complex
response labeled as emotional arousal. Indeed, the basic premise of Ellis '
(1962) cognitive-rational-emotive therapy is that much, if not all, emotional suffering is due to the irrational ways people construe their world,
and to assumptions they make which lead to self-defeating "internal
sentences" or self-statements which exert an adverse effect on behavior.
Recent research by Meichenbaum (1972) indicates that considerations
of self-statements as potential modifiers of behavior might fruitfully be
incorporated) into the standard SD procedure and might even be operating in the current technique in a hitherto overlooked fashion (e.g.,
Lazarus, 1968).
In an initial experiment he compared a cognitive modification procedure with SD and a no-treatment control group in reducing test
anxiety. The cognitive group was first made aware of their worrisome
self-verbalizations with respect to test situations. They were then trained
to relax and to self-verbalize task-relevant and encouraging statements
during imagery of coping with the various aversive hierarchy scenes.
This procedure is in contrast to the traditional SD method, which does
not deliberately include constructive self-statements and which entails
"mastery " rather than " coping " i magery, i.e., the client imagines himself
enacting the feared behavior calmly and with success. The cognitive
modification group produced a significantly greater reduction in test
11
DAVISON AND WILSON
FEAR REDUCTION IN SD
anxiety in a posttreatment analogue test situation and on self-report
measures than the SD group, which was superior to no treatment. An
additional finding was that the cognitive group alone reported a posttreatment increase in facilitative anxiety (cf., Alpert & Haber, 1960),
indicating that these Ss came to interpret arousal as facilitative, as a cue
for task-relevant, constructive action, like relaxing and self-verbalizing
in a nondefeating manner. Meichenbaum 's theorizing, as well as his data,
appear to be consistent with the views of Goldfried (1971), who recommends that, during SD, clients be instructed not to terminate an aversive
scene when fear is elicited, but rather to attempt to relax away any
tension so as to acquire the general skill of coping with anxiety. Further
research will he required to tease apart the different components of
Meichenbaum's cognitive modification of SD, viz., "mastery" versus
"coping" imagery, verbalizing constructively rather than defeatingly or
not at all, etc. The approach, however, illustrates well how research into
cognitive factors in SD might yield an improved, more truly multifaceted therapeutic method for treating the various specific dimensions
of fear.
consequences of a particular action and thereby overcomes his irrational
fear. As London noted, there is a marked similarity between this position
and the explanation of the extinction of avoidance behavior in the animal
laboratory in terms of discrimination learning, or the detection of changes
in the controlling reinforcement contingencies (Wilson & Davison,
1971). The necessary operations for the elimination of the behavior
would seem to be the same in both instances, i.e., arranging for nonreinforced exposure to the previously avoided stimuli, covertly or
overtly (Davison & Wilson, 1972). This procedure may be described
as " decreasing expectancy of disastrous consequences " (Beck, 1970a,
p. 4), or "increasing objectivity, i.e., discriminating between real and
fantasied danger " (Beck, 1970b, p. 196); but, whether any specific
theoretical or therapeutic advantages are to be gained by such cognitive
descriptions has still to be demonstrated. It is on the basis of these
descriptions of events in cognitive terms and the fact that covert activities are involved that Beck labels SD as a "cognitive therapy" as
opposed to a "behavior therapy," a step which Bergin (1970) heralds
as "startling and persuasive," but which might simply reflect differences
in labelling behavior.
10
Terminological Note on the Word "Cognitive" in SD
"Cognitive" is a word widely used by different people with different
meanings. Accordingly, there is some confusion and controversy as to
its precise meaning in behavior modification (cf., Bergin, 1970; Nawas,
1970). Bandura (1969) and Mi schel (1968) both refer to "cognitive
desensitization" and "cognitive counterconditioning." Theirs is a descriptive usage, denoting the involvement of human symbolic processes like
imagery (covert self-stimulation) : their explanatory framework, however, is still conditioning. Similarly, Meichenbaum (in press) assumes
that cognitive phenomena (covert behavior) obey the same laws as overt
behavior and he thus maintains a conditioning conceptualization (cf.,
Ullmann, 1970). On the other hand, Valins and Ray's (1967) reference
to "cognitive desensitization" postulates a specific explanation of SD in
terms of cognitive processes they regard as having nothing to do with
conditioning principles hut drawn from attribution theory. This distinction is very evident in Marcia et al. (1969), who also differ from
Valins and Ray 's use of the term by equating a cognitive interpretation
with general expectancy of gain or placebo factors in any treatment
technique.
"
Cognitive explanations " of SD are often put forward as alternatives
to conditioning formulations when, in fact, the presumed difference
might only be semantic. Thus, London (1964) first suggested that during
SD the client learns to discriminate between realistic and unrealistic
SOCIAL REINFORCEMENT FACTORS IN SD
Another factor suggested as responsible for the success of SD is the
role of the therapist as a social reinforcer of nonfearful responses. Wagner and Cauthen (1968) gave two Ss two sessions in relaxation training,
followed by four sessions during which they were encouraged to relax
while being rolled on a lounger toward a female assistant holding a
snake. Their instructions were to signal when they became even slightly
tense, at which time they were rolled back a few feet before proceeding
once again. Three other Ss were given a shaping procedure, during
which they were likewise rolled slowly towards the snake, without prior
training in relaxation and having been instructed to signal tension in
the same manner. Each time S indicated that she wanted to be moved
closer, E praised her. The subjects improved markedly, results which
the authors suggested favor an operant conditioning interpretation of
desensitization.
Aside from the very small N, the lack of a pseudotherapy control
group (perhaps in this instance a group praised for signalling anxiety
rather than for indicating closer approach) makes it impossible to
attribute the improvement of the shaping group to the contingency of
approach behavior with approval.
Leitenberg et al. (1969) compared two main experimental groups.
One group received SD embellished with "therapeutic instructions" and
12
DAVISON AND WILSON
praise for progressing up the imaginal snake hierarchy, while the other
SD group did not receive these additional comments. Results showed a
superiority of the former over the latter and over a no-treatment control
group, the "pure" SD group faring little better than the no-treatment
control (yet showing within-group improvement). As pointed out earlier,
however, their therapeutic instructions were, in effect, a placebo manipulation emphasizing the efficacy of SD therapy. As a result, the similarity
the authors draw between their procedure and a study by Ayllon and
Azrin (1964) is inappropriate, since in this latter experiment instructions
specified which behaviors would be reinforced. Positive reinforcement
was said to have been provided the embellished group in the form of
praise during each session following completions of imaginal items, as
well as following a 15 min in vivo exposure to the snake. In contrast,
the pure SD group was never praised for progress through the imaginal
anxiety hierarchy, and, further, were told that the in vivo session was
intended to refresh their memories of what the real snake looked like
so as to sharpen their images. Whether selective positive reinforcement
was present is not possible to determine; stimuli presented contingent
on a response should not he classified as positive reinforces
unless it
can clearly be shown that they have worked to increase the behavior. In
this study, we cannot know whether the contingency was of any importance at all. The experimenter was clearly more supportive and more
friendly for this group than for the pure SD group, and noncontingent
praise might have worked just as well.
Oliveau
et al. (1969) investigated the instruction and reinforcement
parameters in the context of a 2 X 2 factorial design. Results showed a
significant effect only for the therapeutic instructions factor (though all
four groups revealed within-condition improvement).
Taken together these two related experiments fail to support an interpretation of the successful outcomes of desensitization in terms of the
shaping of approach responses. The superiority of the instructions-plusreinforcement SD group in the Leitenberg et at. (1969) study is, in
view of the Oliveau et al. (1969) findings, likely due to the "therapeutically oriented instructions, " which may have provided suggestive
influence on Ss rather than "emphasis on defining and attaining specific
behavioral objectives " ( Oliveau et al., 1969, p. 32). Perhaps one could
shed light on this issue by creating an SD group which received placebo
suggestions but instructions which would specify behavioral objectives at
variance with those expected from SD.
Barlow, Agras, Leitenberg, and Wincze (1970) compared SD with
what was termed a "shaping" procedure. Shaping entailed providing a
snake-fearful volunteer the same list of 19 items as constituted the
FEAR
t
REUCTION to
Si)
13
imaginal hierarchy for SD Ss, this list being virtually identical to the
behaviors asked of Ss during the pre- and posttreatment assessments.
S was told that repeated practice is useful in reducing fears, and that
she should therefore enter the room alone where the snake was caged
and practice approaching the snake along the lines of the 19-item list.
S was to perform as many or as few steps as she could before returning
to E in the neighboring room where any reported improvement was
amply praised. Both groups showed significant improvement, with the
shaping condition more effective.
The first interpretation made by the authors is that operant conditioning of overt approach behavior (ignoring any mediating anxiety)
was shown to be superior to SD, which presumably counterconditions the
mediating anxiety drive. However, they suggest also that both SD and
shaping (as here employed) might operate in the same way by providing for exposure to aversive stimuli without reinforcement of the fear.
This extinction formulation, similar to that proposed by Wilson and
Davison (1971), was postulated to explain the efficacy of both procedures, with the differences found here possibly attributable to the use
of real-life stimuli in the shaping procedure and imaginal stimuli in
SD. Indeed, in an earlier study ( Barlow, Leitenberg, Agras, & Wincze,
1969), it was shown that pairing relaxation with the real object leads to
more effective behavior change than does the standard SD procedure,
a finding consistent with Davison's (1968) stimulus-sampling proposal
for the failure of imaginal SD to effect complete transfer to the real life
situation.
It is difficult to accept the suggestion that the " shaping " procedure
used in this study is necessarily true to its name. As in the Leitenberg
et al. (1969) study, the authors did not demonstrate that the contingency
between behavior and "reinforcer " was important. Further. a close
examination of the "shaping " procedure reveals that what is actually
"
reinforced" (i.e., greeted with praise by E) is S ' s verbal report of what
he had just achieved; the increased approach behavior itself is not
'reinforced," nor is the extent of actual approach behavior ever objectively evaluated by E.
Davison and Wilson (1972) have contested Wilkins ' (1971) conclusion that these studies document the importance of the therapist as
a social reinforcer within SD. In addition to the above mentioned problems, they noted several studies in which contact with the therapist was
intentionally minimized (e.g., Kahn & Baker, 1968 ; Lang, 1969) without
nullifying the efficacy of SD. The conclusion drawn by Wilkins is that
`
These variables (expectancy of gain and social reinforcement from the
therapist) in the therapeutic relationship appear to be quite powerful
14
15
DAVISON AND WILSON
FEAR REDUCTION iN SD
in that they can have an immediate and long-term effect following very
minimal contact with the therapist " (p. 313). We fail to understand the
logic of this reasoning, based, as it is, on data that show the effectiveness
of SD under conditions of little if any direct social contact with another human being, at least during the SD procedure itself. Murray and
Jacobson (1971 ) derive the same illogical conclusion from the same data
as Wilkins, arguing that the success of Lang's DAD (Lang, Melamed, &
Hart, 1970), does not "necessarily reduce the importance of the social
aspects" of treatment, since a machine is man made and exerts influence
within the context of a helping relationship (p. 726). Clearly this type
of reasoning is irrefutable and hence meaningless since it removes the
issue from the possibility of critical experimental testing.
Though not dealing directly with SD, a study by Rimm and Mahoney
(1969) raises some interesting questions regarding the possible role of
shaping in reducing the kind of avoidance behavior which desensitizers
deal with. They assigned snake-fearful volunteers to one of three groups:
a shaping group, a noncontingent reinforcement group, and a no-treatment group. The shaping Ss were told that they would earn a number
of tokens, later exchangeable for "a significant amount of money" for
every task they could complete in the same graded series of approach
behaviors that had been used in a pretreatment assessment. As in the
pretreatment assessment, S was required to remain at a given stage for
at least 15 sec ; and the treatment was terminated if, after 1 min, S
could make no further progress. The dispensing of tokens was quite
salient during this shaping treatment. Noncontingent Ss were simply
told that they would get money for participating in the experiment, but
no mention was made of any relationship with their performance; in
actuality, the number of tokens they received was matched to a shaping
subject to whom each S was yoked, and bore no consistent temporal
relationship to successful approach behavior. Results showed no differences among the three groups and no treatment effects of any kind. On
the assumption that perhaps the tokens were not powerful enough
incentive, Rimm and Mahoney attempted to shape four additional Ss
by offering actual money during the treatment, up to $10. Again, no
treatment effects were obtained.
In explaining their failure to obtain treatment effects Rimm and
Mahoney suggest that a necessary requirement for successful employment of operant procedures in such a situation is that Ss during treatment exhibit a reasonable approximation to the desired terminal behavior. This consideration was also voiced by Lazarus, Davison, and
Polefka (1965), i.e., that operant shaping of inhibited approach responses is of questionable utility if the mediating fear is so great as to
preclude the emission of even small approximations of criterion approach
behavior. On the other hand, a recent experiment by Leitenberg, Agras,
Butz, and Wincze (1971) demonstrates that clinically phobic patients
can reduce their avoidance behavior merely by being encouraged to
expose themselves to the source of their fears, with no explicit attention
being paid to the direct reduction in mediating anxiety. It may indeed
be, therefore, that properly arranged conditions for graded exposure
within an operant shaping paradigm can effectively eliminate even
severe degrees of avoidance. As regards the role that the desensitizing
therapist might play in reinforcing approach up the imaginal hierarchy
via attention paid during the maintenance of relaxation, it should be
pointed out that relaxation precedes every imaginal exposure, and when
a S does signal anxiety, i.e., "avoids," he is at that time accorded the
most attention by the therapist, who spends extra time before the next
item presentation in helping the subject/client relax once again.
IMAGERY, INTROSPECTION, AND BEHAVIORISM
It is sometimes suggested that Wolpe's real contribution lies not in
the application of learning principles to the handling of clinical problems, but in drawing attention to the therapeutic properties of imagery
and introspection. Perhaps the best-known exposition of this viewpoint
is Weitzman ' s (1967) article, which emphasizes the overriding importance of the flow of mental imagery during the presentation of
scenes in SD. He reports transformations of imagery akin to observations
made by psychodynamic therapists and cites the spontaneously made
comment of one of his clients which is said to signify the fact that the
client had gained therapeutic insight into his relationship with his mother.
These observations derive from Weitzman' s own interviews of six clients
undergoing SD therapy with him, and on the basis of these clinical data
he rejects as simplistic the view that conditioning is operative in SD
and asserts that the "dynamically rich" imagery of his clients "stretches
the analogy to Wolpe's procedure rather thin."
Basically Weitzman is reiterating the now classic antibehaviorist objection that an S-R conditioning formulation can never, ipso facto,
conceptualize complex mental processes. The reply to this objection is
equally unoriginal: presenting a tonal CS to a cat and asking a client to
i magine being criticized by his mother are clearly topographically different events, but can be, and have been, shown to enter into similar functional relationships between antecedent and consequent events. Kimble
(1967) points out that the term stimulus (or preferably, antecedent condition) "in addition to referring to specific physical objects, " also includes
"independently specifiable circumstances such as the number of trials
17
DAVISON AND WILSON
FEAR REDUCTION I N SD
in an experiment, the time since the last trial, instructions to Ss, and so
on" (p. 79). The important issue, as Kimble continues, is whether or
not we can specify the lawful effects of these variables on behavior. In
this respect the controlled, voluntary induction of aversive imagery in
humans has been empirically shown to have the same measurable effects
as the application of a physically defined stimulus (cf., Craig, 1969;
Grossberg & Wilson, 1968; Miller, 1935). Furthermore, in their impressive
research program, Lang and his associates have shown that autonomic
responses to imaginal stimuli bear a close resemblance to the parameters
of conditioning (Lang et al., 1970). Such data suggest that conditioning
formulations might indeed prove fruitful in conceptualizing covert processes and challenge Breger and McGaugh 's (1965) contention, supported
by Weitzman, "that the use of the terms stimulus and response in SD
are only remotely allegorical to the traditional use of these terms in
psychology" (p. 340).
Aside from these logical considerations, Weitzman's basis for these
observations is highly suspect. It is hardly surprising that the uncontrolled, highly subjective analysis of six clients currently being seen in
therapy by him generated a wealth of "dynamically rich" imagery, for it
has become passe for students of therapy to note that every therapist
can point to his clients experiencing and enunciating things in accord
with the clinician ' s theoretical orientation. The social influence process
and examiner-bias effects are too well-known to allow substantial confidence to be placed in these highly suspect "data. " We ourselves have
conducted an extensive series of interviews with clients we have desensitized and have seldom if ever found evidence for Weitzman 's
observations. In those cases where transformations of the instructed image
occurred (and were encouraged) no discernible improvement followed
which could have indicated the critical effectiveness of that flow of
imagery. (If the reader finds our own clinical observations less than
convincing, then our point regarding Weitzman 's data has been made!)
subject of two spirited sets of exchanges of differing theoretical interpretation (Davison & Valins, 196S, 1970; and Wolpe , 1969, 1970; Wilkins,
1972; and Davison & Wilson, 1972). In this paper we have pointed
out some methodological and conceptual inadequacies in nearly all of the
research and theorizing clone to date.
Ss in most of the studies reviewed here were volunteer college students
with a specific fear of snakes or spiders. Similar research needs to be
clone with truly clinical populations of anxious clients, for whom the
issues of expectation of therapeutic gain and cognitive relabeling are
probably more complex and possibly different from those encountered
.
observes, it
in Ss employed in analogue studies. As Bandura (1969)
might well be that the induction of auspicious cognitions can modify
behavior in some cases of only mildly anxious individuals, but there must
remain considerable doubt as to whether this strategy is effective with
intense fears and well-established patterns of irrational avoidance
behavior.
In a more practical sense, with the exception of Meichenbaum ' s
promising initial efforts, the failure of the studies reviewed here to
isolate the "active ingredients" of SD does not compel any major
procedural modification of the basic technique. However, fu rther research on the question of " coping imagery " and the client'
r
ing induced imagery might call for changes in the
sel-vrbaiztondu method
as it is currently practiced. Finally, to conclude in a clinical vein, we
wish to emphasize that practitioners should continue to use SD within
the context of an appropriate therapist–client relationship, and to utilize
client expectancies of improvement, not because these are necessarily
critical factors within the boundary conditions of the specific SD paradigm (Evans, 1973), but for wider reasons related to sound clinical
practice (Lazarus, 1971; Wilson. Hannon, & Evans, 1968).
SUMMARY AND IMPLICATIONS
ALPERT, R., & HABER, R. N. Anxiety in academic achievement situations. Journal
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AYLLON, T., & AZRIN, N. Reinforcement and instructions with mental patients.
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BANDURA , A. Principles of behavior modification. New York: Holt , 1969.
BARLOW, D. H., Acs AS, W. S., LEITENBERG , H., & WINCZE, J. P. An experimental
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BECK, A. T. Role of fantasies in psychotherapy and psychopathology, Journal of
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BECK, A. T. Cognitive therapy: Nature and relation to behavior therapy. Behavior
Therapy, 1970b, 1, 184-200.
16
In general, it appears that presently available research into cognitive
and social variables has thus far produced little by way of convincing
evidence for explaining the effective process mechanisms involved in
SD. In view of this lack of supporting evidence the enthusiastic advocacy
of " cognitive " as opposed to traditional conditioning explanations of SD
is premature (e.g., Murray & Jacobson, 1971; Weitzman, 1967; Wilkins,
1971). Behavior therapy as a whole, and SD in particular, has not
escaped the now classic "cognitive versus conditioning " controversy
within psychology, and the issues involved have already been the
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