The reduction of anxiety in children: a comparison of the effects of 'systematic desensitization in vitro' and 'systematic desensitization in vivo'

Twenty-four children between the ages of 5 and 10. selected on the basis of fear of water, as determined by parents and swimming teachers, were divided into two experimental groups and one control group. One of the experimental groups was treated with four sessions of in vitro desensitization (gradual imaginal exposure to fear evoking stimuli plus relaxation), followed by four sessions of in vivo desensitization (real-life exposure to fear evoking stimuli plus relaxation). The other group received eight sessions of in vivo desensitization. The control group took part only in the tests, which were administered at the commencement of treatment, after four sessions, and at the end of the course of treatments. In testing, a behavior observation record was used to score the subject's behavior in the given situation; in addition, two teacher's records were used, in which swimming teachers recorded their evaluation of the subject's anxiety in each situation.Better results were achieved by desensitization in vivo than by desensitizalion in vitro or by the control procedure. No differences were found between the latter two groups. It could not be demonstrated that desensitization in vitro increased the effectiveness of subsequent desensitization in vivo     

The contribution of relaxation and expectancy to fear reduction via graded, imaginal exposure to feared stimuli

Speech phobic subjects received five treatment sessions under either positive or neutral expectancy set. Therapy conditions included hierarchy exposure with contiguous relaxation (desensitization), exposure with noncontiguous relaxation, exposure only, and no-treatment. Expectancy had virtually no outcome effects. Desensitization was superior to the other conditions on subjective outcome measures. In contrast to the two exposure conditions without contiguous relaxation, desensitization resulted in increased imagery vividness, greater cardiovascular response to the first visualization of the initial hierarchy scene, and greater declines in cardiovascular response within repetitious visualizations of scenes and across initial visualizations of increasingly anxiety-provoking scenes. Expectancy significantly influenced both fear ratings and cardiovascular response to scenes during the first session, the latter effect disappearing after the first session. The results are discussed in terms of recent theorizing regarding the role of relaxation and expectancy in desensitization.     

Using humor in systematic desensitization to reduce fear

Effectiveness of systematic desensitization for fear reduction, using humorous hierarchy scenes without relaxation, was tested. Participants were 40 students highly fearful of spiders. Using a 24-item behavioral approach test with an American tarantula, participants were matched on fear level and randomly assigned to 1 of 3 treatment groups: (a) systematic desensitization, (b) humor desensitization, and (c) untreated controls. Each participant was seen for 6 sessions, including pretest and posttest. Analyses of covariance of posttest scores revealed that the 2 treatment groups showed greater reduction in fear than the controls on 3 measures but did not differ from each other. Therefore, humor in systematic desensitization reduced fear as effectively as more traditional desensitization. This finding may have therapeutic applications; however, it may also be applicable in advertising to desensitize fear of a dangerous product, such as cigarettes.     

The role of mental relaxation in experimental desensitization

Certain evidence indicates that training in peripheral muscle relaxation is not an essential factor in the successful experimental desensitization of phobias. Rachman (1968) has suggested that a sense of calmness or mental relaxation is the necessary component and that all the preliminary training techniques leading to successful desensitization, have, as the basis for their success, the inadvertent induction of this state of mental calmness. The direct induction of mental relaxation then, ought to be at least as effective an adjunct to desensitization as training in muscle relaxation. Using spider phobia as the target behaviour, the present study compared the effectiveness of (a) hierarchy presentation paired with deep muscle relaxation; (b) hierarchy presentation paired with instructions to feel calm and relaxed and alternated with imagining a pleasant scene; (c) a combination of these two procedures paired with hierarchy presentation; and (d) a placebo control procedure. The treatment groups all improved significantly more than controls and there there were no differences between treatments. The results were seen as offering strong support of Rachman's position. Both theoretical and practical implications of the results are discussed with consideration being given to the nature of “mental calmness”.     

Fear decrement to anxiety hierarchy items—Effects of stimulus intensity

The effects of hierarchy item intensity and duration of presentation on intra-item fear decrement were assessed with regard to systematic desensitization. Forty-eight color slides of snakes were scaled and ranked for anxiety value with the psychophysical technique of magnitude estimation by 30 female snake phobics using two response methods: verbal report and a non-verbal report instrument, the hand dynamometer. Seven test slides, spanning the scale range, were shown for 257 sec to 42 additional subjects who rated their fear level on 10 separate occasions using the hand dynamometer and verbal report. For all slides significant fear decrement occurred as a function of duration and the fear decrement across time was greater for slides of higher intensity. Negative exponential functions with similar slopes were found to fit the data for each of the slides, indicating that for each slide the same percentage of the total amount of fear decrement was lost per unit of time. The implications of these results and techniques are discussed for desensitization theory, research and therapeutic procedure.     

The contribution of relaxation to symbolic modeling in the modification of dental fears.

Studies of symbolic modeling suggest that it is a technique which is at least as effective and more efficient (faster) than imaginal desensitization in the treatment of fears (Bandura el al., 1969; Woody and Schaible, 1969). Bandura et al. (1969) assessed the contributions of relaxation to the procedure and found less subjective anxiety and greater positive attitude change with relaxation but no significant differences in oven behavior nor in generalized anxiety reduction. In this study the ‘symbolic modeling only’ subjects received their treatment after they and the other subjects had received the original post-testing assessment. The present experiment was an attempt to assess the contributions of deep muscle relaxation to symbolic modeling without such confounding and with a more nearly clinical population. Dental fear represents a ‘near clinical’ phobia which satisfies Bernstein and Paul's (1971) criteria for analogue desensitization research. That is. dental phobics exhibit a strong, costly and distressing avoidance response which increases in strength as a function of exposure despite high demand.     

Avoidance behavior and perceived arousal

Previous investigations of the effects of bogus arousal feedback on approach toward an aversive stimulus have failed to separate two conceptual issues: (1) the influence of perceived anxiety on approach behavior, and (2) the degree to which perceptions of decreased anxiety are central to systematic desensitization. The present research deals with only the first of these issues. The procedure required each subject to attach a microphone to his or her chest and approach a snake. Bogus heartbeat feedback was presented concurrently with the subject's approach. In Experiments 1 and 2, self-reported snake phobics approached more with a constant than with an accelerating heartbeat. Nonphobics in Experiment 2 were not systematically influenced by the feedback. In Experiment 3, subjects with moderate fear, but who had stated that they could pick up a snake, behaved like the previously tested nonphobics; moderate fear subjects who had stated uncertainty about their ability to handle a snake behaved like previously tested phobics. In no case did postexperimental self-rated fear of snakes yield a difference between feedback conditions. The results are discussed in terms of the attributional analysis of emotional behavior.     

Stimulus hierarchy generalization in systematic desensitization

A group of snake phobic Ss were desensitized to the first 5 items of a standard 7 item snake fear hierarchy in which the items were ordered on the basis of distance from a snake. This group and a no-treatment control group (which did not receive the desensitization) were treated for fear of all the hierarchy stimuli in terms of ratings both before and after the desensitization. The Ss rated their fear responses to all the stimuli as presented to them in (1) real form (2) by slide, and (3) in imaginal form. The results verified all four experimental hypotheses: (1) The experimental Ss showed greater fear reduction than the control Ss to both the training stimuli (the stimuli on which desensitization done) and the generalization stimuli (the other two stimuli), (2) The systematic desensitization (SD) group showed (a) more fear reduction to the last training stimuli than to the lower generalization stimulus and (b) more to the latter than to the higher generalization stimulus, (3) The SD group showed less fear reduction to the generalization stimuli in their real form than in both the slide and imaginai modalities (in the desensitization each stimulus presentation was done first in slide form and then in imaginal form), and (4) There were significant overall individual differences in generalization of fear reduction to the generalization stimuli.     

Reduction of examination anxiety and ‘stage-fright’ by group desensitization and relaxation

The results of the experiment in group desensitization, relaxation and imagination of exam situations in groups of children (n = 23) and students (n = 13) show that systematic desensitization is an efficient method for reducing stage-fright. Some transient positive effects were also achieved with a modification of the Schultz method of relaxation. Interviews, a Fear Survey Schedule and a test of palmar perspiration were used in the assessment of effects. The main conclusions are concordant with previous studies in desensitization (e.g. Lang and Lazovik, 1963; Rachman, 1965, 1966 a and b; Lazarus, 1961; Paul and Shannon, 1966) and the present results provide interesting comparisons.     

The efficacy of progressive relaxation in systematic desensitization and a proposal for an alternative competitive response--the relaxation response.

The theoretical basis of systematic desensitization is reciprocal inhibition in which an alternative, competitive response to anxiety is conditioned to arousal-producing, phobic stimuli. Abbreviated training in progressive relaxation is believed to serve as a competitive response to anxiety by decreasing autonomic nervous system activity. However, physiologic studies of progressive relaxation have not substantiated that its practice is associated with such decreased autonomic activity. Consequently, the use of progressive relaxation has been a confounding factor in the determination of the function of reciprocal inhibition in systematic desensitization. To confirm and refine the theoretical constructs of reciprocal inhibition, it is necessary to test the effects of a response which is competitive to the anxiety response. Such a response may be the relaxation response which is characterized by physiologic changes consistent with decreased autonomic nervous system activity. Derived from meditational practices, techniques which ehcit the relaxation response incorporate the element of focused attention which has been implicated as a critical factor in systematic desensitization. Thus, the use of the relaxation response should be a more appropriate method than progressive relaxation if the therapeutic usefulness of systematic desensitization is indeed due to reciprocal inhibition.     

Repeated exposure of flight phobics to flights in virtual reality

The present study examined the effects of repeated exposure of flight phobics to flights in virtual reality (VR). Flight phobics were randomly assigned either to complete one VR test flight followed by four VR exposure flights (VR group; N=15) in one lengthy session or to complete one VR test flight followed by a lengthy relaxation training session (relaxation group; N=15). All participants completed a second VR test flight at the end of the session. Fear reports and physiological fear reactions (heart rate, skin conductance level) during VR exposures were registered, and fear of flying was assessed psychometrically from 3 weeks before to 3 months after exposure. Exposure to VR flights elicited subjective and physiological fear responses in flight phobics, and these responses attenuated within and across VR flights. Fear reduction associated with repeated VR exposure was greater than fear reduction caused by relaxation training. Fear of flying improved in both treatment groups, but several outcome measures indicated greater effects in the VR treated group than in the relaxation group. These findings indicate that exposure in virtual reality may offer a new and promising approach for the treatment of fear of flying.     

Motor and cognitive relaxation in the desensitization of anger

Three procedures were assessed to determine their effectiveness in reducing anger. The procedures were: desensitization, desensitization with cognitive relaxation, and desensitization with the absence of relaxation training. Anger was aroused by exposing white males, selected for their reports of anger toward blacks, to black racial stimuli. The desensitization group reported reductions in anxiety and disgust relative to a no-treatment control group. Therapist ratings indicated reductions in anger for Ss in both the desensitization and desensitization with cognitive relaxation groups. In addition the latter group reported reductions in anger concurrently with increases in diastolic and systolic blood pressure. Post-hoc analyses indicated that Ss for whom desensitization was most effective reported less anger after the pretreatment anger arousal procedure, greater depth of relaxation during treatment, and were liked more by their therapists. These Ss also reported a greater reduction in ethnocentrism and a trend toward lower overt hostility following treatment.     

The Problem of the Meaning of Words Based upon Observation of Aphasic Patients

Research has indicated that massed systematic desensitization can be effective. There is no definite evidence, however, of the superiority of massed or spaced therapy. The present study investigated the effects of massed and distributed systematic desensitization upon a spider phobia. Eighteen Ss were given a fear hierarchy before therapy and then after therapy. Analysis of the results suggests that massed and distributed sessions do not differ significantly in effectiveness, which supports Suinn and Hall (5).     

Prior Exposure to Creatures From a Horror Film

This experiment assesses the impact of two exposure strategies on children's emotional and cognitive reactions to a frightening movie scene. Children from two grade levels (kindergarten and first vs. second through fourth) received a desensitization treatment in which modeled exposure to a live earthworm was factorially varied with exposure to graphic photographs of worms taken from a horror film. Children then viewed a frightening scene involving worms taken from this same film. Results indicated that exposure to photographs increased children's enjoyment of the movie segment and reduced fear reactions to the scene. In contrast, the live exposure strategy was effective in reducing fear reactions to the movie only among boys. However, live exposure did alter children's affective reactions to and judgments of worms themselves. The findings are discussed in terms of current theories of desensitization and information processing.     

Sensitivity to phobic imagery: a sensory decision theory analysis

The effects of deep muscle relaxation on anxiety were studied in a systematic desensitization context. A Sensory Decision Theory analysis of anxiety ratings to controlled imagery showed that relaxed Ss were significantly more sensitive to phobic properties of the controlled imagery than nonrelaxed Ss. The results are discussed in terms of Wolpe's theoretical basis for systematic desensitization. Sensory Decision Theory is presented as a useful technique for measuring the effects of therapy on emotional states.     

The role of neuroticism in startle reactions to fearful and disgusting stimuli

It has frequently been observed that negative moods potentiate the startle reflex to unexpected, threatening stimuli. However, recent work from our laboratory suggests that this effect relates primarily to the emotion of fear or anxiety, while stimuli which evoke powerful feelings of disgust can in some circumstances inhibit the startle reflex. In this study we reanalyse data from 42 subjects in whom eye-blink amplitudes to an auditory probe were measured whilst viewing emotionally arousing film clips. Classifying the negative film clips into separate categories of “frightening” vs “disgusting” revealed a previously undetected interaction with EPQ Neuroticism. High N subjects showed greater startle reactions than low N subjects under fearful conditions but low N subjects showed greater startle when disgust was evoked. This suggests that Neuroticism may increase vigilance where evasive action is possible but promote emotional blunting when escape is not an option.     

Short-term desensitization therapy

R has raised the possibility that behavior therapy procedures can benefit from even further departures from traditional psychotherapy formats. Although behavioral approaches such as desensitization therapy are distinctive departures from the verbal psychotherapies, there is still an implicit commitment to one traditional approach: the reliance upon one or two weekly appointments. Clients being treated for phobias, for example, are typically seen for desensitization sessions twice weekly. Yet, both theory and current research argue for more frequent meetings as being more effective. Robinson and Suinn (1969) saw clients with spider phobia daily for five consecutive days, meeting one hr per day. Clients were tested on a behavioral task prior to and following massed treatment. Results showed that prior to therapy, none of 20 clients were able to place their hands near the spider; following massed treatment, all clients improved, 13 clients placed their hands within 12 in. of the spider, 2 touched the spider and 1 client stroked the 4 in. spider twice as it moved across the cage. Suinn and Hall (1970) relied upon an even shorter treatment period: students with test-taking anxiety were desensitized completely within 24 hr. These clients were trained to relax and exposed to hierarchy items from 1–4 p.m. on Friday and 8–12 noon the next day. Results showed that the marathon treated clients showed recoveries to the same degree as that achieved in a group treated over a course of 4 weeks. Theoretically, massed treatment should be more effective than spaced treatment. This is based on the view that massed practice would lead to the extinction of fear or anxiety responses since this method capitalizes upon two factors: (1) counterconditioning, whereby the fear stimulus becomes conditioned to relaxation instead of anxiety, and (2) conditioned inhibition, whereby the anxiety responses become ‘fatigued’ and non-responding is reinforced. Implosive therapy (Stampfl and Levis, 1967) appears to be basically a type of massed practice in which the client is continuously exposed to extremely frightening scenes to extinguish the fear. In implosive therapy the client is kept anxious during the treatment; in massed or marathon desensitization, the client is relaxed throughout the sessions. The purpose of this report is to summarize some results achieved through massed desensitization.     

Play desensitization of fear of darkness in preschool children.

Systematic desensitization therapy (SDT) is considered to be a technique of established effectiveness in reducing monosymptomatic fears (Paul, 1969a, 1969b), yet little systematic research has been done to investigate the merit of desensitization procedures in modifying children's behavior. The few available controlled studies (Miller et al., 1972; Obler and Terwilliger, 1970; Oliver, 1971) on desensitization with children have produced equivocal results. Although imagery and relaxation have been reported of benefit when used separately (Graziano and Kean, 1971; Lazarus and Abramovitz, 1962), evidence suggests that the usual combination of imagery and relaxation is not effective in reducing children's fears (Miller et al., 1972). Investigators in this area have often modified traditional SDT to include alternatives to imagery such as pictures, drawings, play (Cassell, 1965; Lazarus, 1960; Obler and Terwilliger, 1970; Patterson, 1965), or in vivo exposure to the feared stimulus (Obler and Terwilliger, 1970). Relaxation has often been replaced with other responses thought to be incompatible with anxiety such as eating (Jones, 1924). Another deviation from traditional SDT has been the delivery of positive reinforcement (food, praise, or toys) contingent upon the child's approaching the feared object (Obler and Terwilliger, 1970; Patterson, 1965). On the basis of such varied techniques, it is impossible to determine which of these procedures constitutes an effective treatment method for children. In the following study, three desensitization procedures involving graded exposure to the feared stimulus (darkness) through symbolic play, were compared to no-treatment and placebo control groups under differing instructional sets. Treatments were designed to determine the therapeutic efficacy of play as a method of stimulus presentation with children, and to determine whether reciprocal inhibition, extinction, operant reinforcement, or instructional set contribute to fear reduction in desensitization with children.     

Psychophysiological responses during analogue systematic desensitization and non-relaxation control procedures

This investigation tested the hypotheses than an analogue systematic desensitization procedure (SD) would be both more effective and more efficient than a comparable non-relaxation control procedure (NRC) with respect to subjective report, behavioral and psychophysiological variables. Phobic subjects responded to slides depicting a feared aversive stimulus. The SD procedure resulted in significantly less reported fear, fewer trials to a criterion level of decrease in subjective fear, and significantly greater decreases in ANS baseline measures. However, measures of behavioral avoidance and measures of decrease in psychophysiological responsivity to the aversive stimuli revealed significant changes within both SD and NRC groups, and no significant differences between the groups, whether or not the groups were equated for number of stimulus presentations. The results, indicating equivalent efficacy and efficiency for the SD and NRC procedures, suggested a limited role for relaxation in systematic desensitization. An extinction or habituation hypothesis was supported at the expense of a counterconditioning hypothesis.     

A physiological model of phobic anxiety and desensitization

The relationship between arousal and phobic anxiety is discussed with regard to recent psychophysiological studies of habituation in normal subjects and in groups of anxious and phobic patients. A physiological model of the mechanisms underlying generalized and phobic anxiety is postulated. Some criticisms of Wolpe's conception of systematic desensitization are offered and an alternative explanation consistent with the above postulate is put forward. This alternative states that the underlying mechanism of systematic desensitization is identical with that of habituation proceeding under optimal conditions (the “maximal habituation” hypothesis). The two accounts of desensitization are compared and contrasted.