Robert Howenstine, Ph.D.
Systematic Desensitization is a procedure for the treatment of phobias originally developed by Joseph Wolpe (1958). Phobias are irrational, excessive, and persistent fears of some particular object or situation. They are characterized by an unwarranted anxiety response to the object or situation and this often leads to significant difficulties in leading normal activities. Wolpe viewed a phobia as a conditioned anxiety response, and its treatment required the reciprocal inhibition of that anxiety response thereby eliminating it. Systematic desensitization was originally a treatment for phobias in individuals with generally adequate cognitive functioning and required their organized assistance in implementing the several components of the treatment plan. Since his original publication, systematic desensitization has been successfully used to reduce a wide variety of phobias, and a number of elaborations and variations on the procedure have been developed (Lazarus, 1968; Firestone, Waters, & Goodman, 1979; Jansson &d Oest, 1983; James, 1985; Levin, & Gross, 1985). However, it has not been widely used with individuals with developmental disabilities. This paper will explore issues that must be addressed in modifying the original procedure for use with individuals with developmental disabilities, and present five case studies that illustrate specific adaptations of the procedure.
Systematic desensitization, as developed by Wolpe, consisted of three primary components. The first was to develop with the individual a hierarchy of anxiety promoting stimuli. The client was asked to imagine a variety of objects and/or situations that induced anxiety, and to rank these in degree of anxiety from one to ten. The therapist worked with the client to develop a list of anxiety provoking stimuli at all levels of the continuum, so that there were only small increments of additional anxiety between each item on the hierarchy. The second component was to teach the client how to relax (a state considered incompatible with anxiety). This was accomplished did by teaching the client to take long deep breaths, and to tighten and relax different muscle groups throughout the body. The third component was the systematic pairing of the relaxation response to the stimuli on the anxiety hierarchy, starting with the lowest level of anxiety. After repeated pairings of the relaxation response with the anxiety response, typically the anxiety was extinguished, and the relaxation procedure was applied to the next item on the anxiety hierarchy. If the anxiety was not eliminated at a particular step, additional stimuli of lesser anxiety level were developed to bridge the gap. This procedure was repeated through all items on the hierarchy, thereby leading to elimination of the phobia. In most cases systematic desensitization was done in an office setting and involved the client imagining objects or situations, but the technique could also be used in real life situations. In general, this procedure was effective in reducing phobias and is an often used treatment option for phobias.
There has been some research to compare the effectiveness of exposure to real situations as opposed to imagined situations. In a review of 24 controlled studies on behavioral treatments (including systematic desensitization) for agoraphobia, Jansson and Oest, (1982) found clinically significant improvements in approximately 60-70% of patients exposed to in vivo stimuli, both following treatment and at six-month follow-up. Patients exposed to indirect stimuli did not do as well. James (1985) reviewed the literature on desensitization treatment of agoraphobia and identified some studies that did not support the superiority of in vivo exposure. He suggested that imaginal and in vivo exposure might be so inextricably confounded that it is not possible to clearly isolate their individual effects. Levin and Gross (1985) examined the role of relaxation in systematic desensitization. They noted that different populations had differences in the ability to generate vivid imagery. Their findings suggested that relaxation helped those with poor imaging ability to produce more vivid imagery, which assisted treatment success. Those with good imaging ability were not particularly assisted by the relaxation component.
There is a significant amount of research on use of systematic desensitization with children without developmental disabilities. Kearney and Silverman (1990) used systematic desensitization to treat a nine-year-old boy with fears of school. They used both imagined and in vivo stimuli paired with relaxation training, leading to successful treatment in 8 sessions. Palace and Johnston (1989) treated a ten-year-old boy with recurrent nightmares. Using progressive muscle relaxation and systematic desensitization, they reduced his nightmares 68%. They then added training in making coping statements to the therapy, and reduced nightmares to 88%. Lastly, they added guided rehearsal of imagined mastery responses to the dream content, and achieved 100% reduction of nightmares. A study by Slifer, Babbitt and Cataldo (1995) employed a behavioral counterconditioning procedure to reduce the anxiety of five children undergoing invasive medical procedures. This consisted of providing preferred play activities to the children to help them into a relaxed state, and then gradually introducing simulated medical procedures. This practice led to a decrease in behavioral distress measures during the actual medical procedures. The children were also provided differential positive reinforcement contingent on engagement with the preferred activities and on compliance with instructions during the medical procedures. Noeker and Haverkamp (2001) report the successful treatment of a 12-year-old boy with photogenic partial seizures who had developed phobic avoidant behavior toward situations with potential photo stimulation. Their procedure consisted of training relaxation through intense contraction and relaxation of facial and hand muscles, teaching relaxing visual imagery (a lake with a stone thrown into it), and gradual exposure to computer and television screen photostimulation. The subject was provided buttons to control the brightness and contrast levels of the screen, to regulate the intensity of the photostimulation and the anxiety it generated. The treatment resulted in complete remission of phobic anxieties.
Lazarus described a variation on systematic desensitization that employed competence and emotive imagery (1968) in which the subject imagined himself engaging in activities with competence and success, as a means of reducing anxiety. King, Cranstoun and Josephs (1989) used this procedure to treat nighttime fears in three young children. This consisted of constructing anxiety hierarchies for each child and also identifying for each child a favorite hero character. The therapist developed scripts of the child and the hero working together to overcome the fears of the child. DuHamel, Redd, Johnson, and Vickberg (1999) described an application of this procedure (along with other behavioral procedures) in reducing stress and anxiety in children undergoing cancer treatment. They identified the childs favorite storybook hero and created a series of stories involving the child and his/her hero. Each story brought the child closer to the feared setting, while the hero helped the child to master the situation. In this manner, the child came to associate the phobic or distressing stimuli with positive feelings of self-assertion and pride. Moran and OBrien (2005) used this procedure in treating an 11-year-old girl with a fear of encountering vomit. They were unsuccessful using physical relaxation with presentation of imagined video and in vivo vomit stimuli. They changed the procedure to have her utilize competence imagery. This consisted of imagining playing her musical instruments, swimming laps in a pool, and practicing yoga postures, all of which were areas of competence for her. Pairing these images to presentation of vomit stimuli led to a successful reduction of anxiety, including in vivo presentations.
Research on the treatment of phobias in persons with developmental disabilities is limited. One case study, Jackson and King (1982), described the successful treatment on an autistic girl who had a phobia of flushing the toilet. She was taught to engage in laughter and mirth as a response incompatible with anxiety, and successfully overcame her fear of flushing the toilet. She was also given a positive reinforcement for flushing the toilet. Another study described the treatment of six children with developmental disabilities and sleeping problems (Didden, Curfs, Sikkema, & deMoor,1998). For one of them, part of the treatment included desensitization to anxiety related to going to bed.
Application of Systematic Desensitization to Individuals with Developmental Disabilities
In considering using systematic desensitization with individuals with developmental disabilities, modifications to the standard procedure are necessary. The first modification is in developing the hierarchy of anxiety provoking situations. Most individuals with developmental disabilities have severely limited ability to assist in this. Therefore the therapist has to generate a hierarchy of anxiety-producing items or situations based upon his/her best estimates of what produces anxiety for the individual. To the extent possible, input should be sought from the individual and other individuals who support the person and have knowledge of the objects and situations that provoke anxiety in the client. The second modification requires using real objects and/or situations to present the anxiety provoking stimuli. Individuals with developmental disabilities are typically unable to imagine anxiety provoking situations with the accuracy and control needed for the procedure to work effectively. The third issue is training the individual in a response that is antagonistic to anxiety. In the cases to be described, the individuals were not able to learn to enter a state of relaxation through long deep breathing or tightening and relaxing of muscle groups, so it was necessary to find another response that was incompatible with anxiety. Use of emotive or competence imagery, which has been successfully used with non-disabled children, is not a choice for the majority of individuals with developmental disabilities as they lack the skills needed for this.
The following five case histories describe the application of systematic desensitization to the treatment of phobias in individuals with developmental disabilities.
Case 1. J.B. was a 32-year-old African-American woman living with one roommate in a two-bedroom apartment. She had moderate developmental disabilities. She was provided daily assistance from a residential support agency. Two months prior to initiating treatment, she had developed a sudden fear of Mylar balloons. Whenever she saw Mylar balloons she would scream, yell, and run away from them. She refused to go into any stores that had them, and she was getting more and more reluctant to leave her apartment for any reason. This agitated her and greatly limited her comfort in doing things in the community. In attempting to identify the origins of this fear, staff did report that shortly before developing this fear, she had taken a ride in a car full of Mylar balloons, on the way to visit a friend in the hospital. Her mother reported that approximately ten years earlier she had had a strong fear of vacuum cleaners, but that this had gradually faded on its own. She had an articulation problem and it was not able to say words clearly. Because of this, it was not possible to learn from her what started this phobia. She did have fairly good verbal comprehension however, and could understand most of what was said to her. Desensitization was explained to her and she agreed to try it.
The treatment plan consisted of weekly visits to her apartment by a psychologist, with residential staff working with her daily in between. Attempts were made to teach her to take long deep breaths and to practice tensing and relaxing muscles groups in her arms and legs. She would inhale and exhale on request, but did so in a tense and tight manner. Repeated attempts to teach her to relax only increased her anxiety over her inability to please the therapist. It was therefore decided to proceed with the presentation of anxiety stimuli anyway. A Mylar balloon was purchased and cut into pieces of various sizes, the smallest being one inch square. These were placed in a paper bag at the opposite end of the living room from where J.B. was seated. She was asked to take several breaths, and then the therapist took the smallest piece of Mylar out of the bag, held it up for four seconds, and then replaced it in the bag. She was then asked if she felt comfortable. If she indicated yes, the procedure was repeated. After three successful tries she was asked if the bag could be moved a step closer. If she agreed, it was moved a foot or two closer and the procedure was repeated until the bag was three feet from her. The bag was then returned to the opposite end of the room, and the procedure was repeated with the next larger piece of Mylar balloon. Each training session consisted of approximately five sets of three presentations. J.B. was praised frequently during this process. This rate of presentation worked very well, and almost never did she indicate anxiety or refusal to bring the bag closer. After six weeks she was comfortable touching a whole deflated Mylar balloon, and a six-inch inflated Mylar balloon was introduced. In two more weeks, she reached the point of being able to touch this inflated balloon, and training was begun with a full size inflated Mylar balloon. By this time staff were reporting she was much more comfortable going out into the community and was starting to use her breathing techniques independently when she encountered a situation that made her anxious.
J.B. did not want to have the full size Mylar balloon left in her apartment between weekly therapy appointments, and therefore the therapist took it with him. This meant that her staff did not have the stimulus to work with her on a daily basis. After three successful sessions with the therapist she was asked if the balloon could be left in her patio closet. She agreed, however, she began showing increased anxiety over its presence, refused to let her staff get it out, and began showing increased fear in going into the community. To honor the commitment to her not to ask her to do anything that was upsetting to her, the balloon was then taken away by the therapist after each weekly session. This slowed down the treatment process some, but after five more sessions she was able to touch the full size inflated balloon. By this time, she was over her fears of going into the community and was comfortable entering stores with multiple Mylar balloons on display. She has had no re-occurrence in this phobia in over five years. It should be noted that her breathing remained tense and jerky throughout the entire treatment.
Case 2. T.M. was a 41-year-old man with Down syndrome. He functioned in the mild range of developmental disabilities. He lived at home with his mother who was 87 years old. T.M. was quite verbal and could read and write at about a third grade level. He was quite sociable and had been fairly active in his community, going to church, community college classes, and a variety of social activities. Fourteen years ago he had heart surgery to close a one-inch hole between his heart chambers. They also removed a walnut sized tumor that was obstructing his arteries. The surgery was successful and substantially increased his energy level. Prior to the surgery he had very little energy and could do almost no physical exercise. However, following the surgery he began having panic attacks. These were very brief, usually no longer than 5 seconds, but they upset him. In the beginning these attacks did not bother him that much or interfere with his community activities. Over the years he gradually became more and more anxious about these panic attacks and thought that being active would bring them on. He was started on Prozac and Nortriptyline a year and a half earlier but had stopped taking them five months prior to beginning desensitization.
At the time that his mother requested assistance, he was afraid to leave the house nearly all of the time, and was unable to go out to participate in his activities. He expressed a fear that he was going to die, and spent most of his time sitting in a rocking chair and rocking. He was even becoming fearful of moving around in the house. Her mother reported that he was also having fearful thoughts such as Do I have a devil inside me? and Could I go to prison. Sometimes he said My head feels like it is cracking, and Its all in my head. Her mother felt that he was getting increasingly anxious and was thinking less and less rationally. The process of desensitization was explained to T.M. and his mother, and they both agreed to give it a try. The therapist told T.M. that the panic attacks might decrease, but they would probably not go away completely. The therapist also expressed that he knew the panic attacks were scary and it took a lot of bravery to keep doing things when he had them, but that the therapist was confident he was a brave man. He was also told that his doctors said the attacks would not hurt him.
Therapy began by teaching T.M. deep breathing in his rocking chair. He was cooperative and worked at the deep breathing and was able to achieve a fairly good level of relaxation. He was also asked to practice squeezing his hand and relaxing it. He was seen once a week at his home, and his mother was asked to practice with him on a daily basis. Simultaneous with starting the desensitization, T.M.s mother approached a psychiatrist for evaluation of medications for panic attacks. Three weeks into the desensitization procedure, T.M. started taking Prozac and Clonezapam to reduce panic attacks.
Each session began with T.M. sitting in his rocking chair and doing some deep breathing. He would then be asked to stand up, take some breaths, and sit down. After several repetitions and assurances from him that he was comfortable, he would be asked to take a step, then return to the rocking chair, breathe, and stand up again. Gradually he was asked to take more and more steps away from his rocker, stop and breathe, and return to his rocker. As he became more and more comfortable, he went down the stairs to the main entrance, then outside on the front porch, then out to the mailbox and back. After six weeks, he was able to comfortably go on walks about the neighborhood on his own. By this point his anxiety over going to activities in the community was eliminated and he resumed his regular activity schedule. He has had no re-occurrence in this problem in over three years.
Case 3. K.R. was a 21-year-old woman with Down syndrome who lived with her parents. She functioned in the moderate range of developmental disabilities. She had some limited speech that was quite difficult to understand but she did understand simple speech fairly well. She had always been a happy and energetic girl and was cooperative and helpful. She was active in a lot of community activities such as Special Olympics and she had a great interest in cars and trucks. She liked to help her father work on his pickup truck. In school, she was well liked and made steady, if slow, progress. The last year and a half in school had been difficult and stressful for her as the emphasis was on vocational training and preparing for post school life and she had a new teacher who pressured her to perform. When the current school year started, she began resisting some assignments, and then finally began throwing herself to the ground as a way to refuse tasks. Her teachers talked to her parents and recommended that they continue to expect her to do her assigned tasks. They agreed with this strategy, but it didnt work and made her even more upset about school. Two months after the start of school, her mother had minor surgery that required her to be in the hospital for two days. K.R. stayed with her grandparents for those two days. At her grandparents, she experienced significant difficulties. She never went to sleep and began acting bizarrely. For example she forgot to take her pants down when she sat on the toilet, she tried to get into everything, and imitated her grandfathers swearing. After his mother came home she refused to go to school or her regular activities in the community. Her parents felt that she had a nervous breakdown. Her doctor put K.R. on Trazadone for sleep and also Depakote for mood stabilization. These seemed to be have some positive effect.
Two months later, K.R. was home all the time, refusing to go to school or even leave the house for other activities, and spending most of the day in bed. Her parents requested assistance and systematic desensitization was suggested to them as a way to overcome her fear of leaving the house. Her mother agreed to work with therapist on it.
Therapy consisted of a weekly session with a psychologist in her home, and started with teaching K.R. to take deep breaths while seated in an easy chair in their living room. She was cooperative but had considerable difficulty taking deep breaths and then relaxing when she exhaled. Her form of deep breathing was quite rigid and tense. She was told that she only had to do things with which she was comfortable, and if she wasnt comfortable, she was to let the therapist know. Once she had a breathing system down, she was asked to stand and take deep breaths and then sit again. As she became comfortable with each step, she was gradually asked to take steps toward the front door, then open the door, go out to the car, open the car door, and get inside the car. With K.R. each step was repeated five times before going to the next step, and the session was ended after going through two steps. Her mother was taught how to do the procedure with her.
Over the course of two months, K.R. completely overcame her anxiety about leaving the house, and returned to an active and happy life in the community. Some of this success is attributable to being careful to only take her to places or activities that she liked such as Starbucks or favorite restaurants. Some new social activities were found for her with support to make sure that she would fit in well at these activities. She did not return to school (her parents preference) and graduated out of school at the end of that year. She has had no recurrence of this problem in over four years.
Case 4. E.N. was a 38-year-old non-verbal man with autism, who had lived with his parents all of his life. He had severe developmental disabilities and needed constant supervision and assistance with many of his basic self help skills. His abilities to communicate and to understand language were very limited. He did participate in social activities for individuals with developmental activities and accompanied his parents in trips into the community. Most of his time was spent puttering around the house, engaging in some ritualistic play, and sitting in a chair. He unexpectedly developed a fear of riding in the car (which had not previously been a problem), and his parents could not identify any particular event that triggered this. Systematic desensitization was suggested to his parents as a possible treatment, and his father agreed to work with the psychologist in implementing it. The plan was for the psychologist to make a home visit once a week to do a session, with his father practicing with E.N. on days in between.
Treatment began by attempting to teach E.N. to inhale on request, but he was unable to develop this response. Attempts were then made to teach him to blow out on his hand (a response that he could experience at a concrete level), and he was able to do this on request. Although he would blow on his hand, it did not appear to be particularly relaxing to him, rather it looked as if he was mildly puzzled by it but willing to comply to humor his father. Using this as the relaxation response, E.N. started in his chair in the living room, blew on his hand, and then was asked to stand, then sit, and then stand and gradually walk nearer and nearer to the car. For a brief period in the beginning, he was also given a sedative (Ativan) an hour prior to the sessions. While this seemed to be helpful, his father soon found it was unnecessary and discontinued its use. Using this procedure, E.N. was able to approach the car, open the door, and sit in the passenger seat in two months time. His father then began taking him on very short rides in the neighborhood, gradually increasing the distance driven, as E.N. seemed comfortable. He periodically showed some anxiety in the car, and the process of extending the length of car rides was a gradual one. After five months, E.N. was taking rides for up to one hour duration without signs of anxiety. There has been no recurrence of this problem in one and a half years.
Case 5. A.W. is a 43-year-old man with autism. He has moderate developmental disabilities and for 12 years has lived in an intensive tenant support home with three other persons with developmental disabilities. He speaks in single words or short phrases that are difficult to understand but he does understand a lot of what is said to him. What he does and doesnt understand is often difficult to tell. He has difficulties understanding social interactions and why some things are appropriate and others arent. He can do a number of tasks but needs a lot of direction. He likes things orderly and he straightens things up around his house. He in not interested in interacting with others much, but over time does develop fondness for staff who help him do things he likes.
For about twelve years he has been afraid to get in a car and be driven places. He totally refuses to get in a car, and so this had made it difficult to get him to activities, doctors appointments, etc. Staff have found a doctor within walking distance, and he also has a job that is within walking distance. If attempts are made to pressure him to get in a car, he starts slapping his head severely and retreats into the house and his bedroom. He also has a fear of being closed in rooms, and gets very upset if anyone attempts to close his bedroom or the bathroom door when he is in the room. Her parents report that they did discipline him when he was at home by sending him to his room and holding the door closed. They also reported that his resistance to getting in cars began when he was riding in vans that became more and more crowded with other individuals. Some attempts were made to force him into the van or cars, which only made his resistance increase.
Therapy with A.W. began two years ago. Attempts were made to explain the process to him, and then he was asked to take some deep breaths. After complying for several breaths, he refused to do any more, despite repeated attempts. Discussions of alternative responses that would be incompatible with anxiety led to deciding to try using food consumption as a relaxing behavior (food would also be a direct positive reinforcer for the target behavior). In addition, it was decided to hide various toys or interesting objects in the car, to attempt to arouse his curiosity in searching for items in the car and thereby offsetting anxiety he might have. The procedure was for the psychologist to make a weekly home visit to conduct a therapy session, and to train residential staff to do similar sessions on a daily basis. Initially, two small packets of snacks and a pop were hidden in the psychologists station wagon. A.W. had no resistance regarding approaching the car and looking in it, as long as he was standing outside it. He would indicate anxiety by making noises, flicking himself with his fingers, or slapping his face if he was more upset. Any time he indicated anxiety, requests were dropped and he was allowed to return to the house if he wanted.
By the end of six months whenever the psychologist drove up, he would immediately come out and initiate the process. First he learned to sit in the back tailgate area a few minutes at a time, while eating trail mix. He wasnt very interested in the non-food items placed in the car, and that was phased out. Within another few months he would open doors on his own and would sit inside the car with his feet in the car (for a while he had sat with his feet out the door) with the door open.
Once he was very comfortable getting in the car, the next step was for A.W. to learn to close the car door. Sessions began focusing on asking him to pull the door shut. He was willing to pull the door in within about 8 to 10 inches of being closed, but wouldnt bring it in more. Efforts were made to teach him to move it in and out repeatedly. It was demonstrated to him on the drivers door how to open it from the inside, and he was shown how to pull the handle to open the door.
He continued to resist this step. Then playing some of his favorite music tapes in the car was introduced. He showed a definite positive response to this and began staying in the car longer. As part of this the engine was turned on, and he did not show anxiety over that. Windows were rolled down to attempt to reduce the feeling of being closed in, but that did not change his resistance to closing the door. It was then attempted to drive the car forward slowly, up to 30 feet, with the door open. After a brief initial startle response the first time, he allowed this to happen and was not disturbed as long as the door was open. It was repeatedly explained to him that he if he closed the door he could immediately open it, and that he would be in control of it. It was also explained that if he did close the door it would be possible to drive to a convenience store where he could get a Slurpee, which he really liked. Despite showing interest in a Slurpee, he would not close the door. The psychologist regularly got out of the car and attempted to gently push in on the door without applying strong pressure, and urged A.W. to let it come in more, but he would only allow it to a certain point.
After several months of no progress, it was decided to give him a sedative an hour prior to the training sessions. This was done and he did appear sedated, but he still resisted the closing of the car door as much as before, and so the sedative was discontinued after five sessions. After two years of sessions, closing the door remained the barrier to successful treatment of this issue. Right at the point of reviewing alternative options, the therapy was put on hold due to budgetary cutbacks.
The first four cases demonstrate that systematic desensitization can be modified to successfully treat phobias in individuals with developmental disabilities. While treatment seemed facilitated if the individual had sufficient understanding to comprehend the procedure, it was only necessary for the individual to be able to comprehend and cooperate with simple instructions for the treatment to be successful. In three out of these four cases, the subjects did not develop a relaxing response, but the response they did make was sufficient to reduce the anxiety they were experiencing. It seemed that having to make a response that required some effort and concentration was sufficient to compete with the anxiety of the stimulus presentation, and thereby lead to its elimination. In addition to use of systematic desensitization, several of these individuals were taking medication and were also provided much praise and positive reinforcement for participating in the treatment. It is not possible to separate out the different effects that these components may have had on the outcomes and it is therefore not possible to attribute all the gains solely to the systematic desensitization procedure.
The fifth case involved use of a more questionable response to compete with the anxiety of the phobic stimuli. Consuming food or drink may well have a relaxing effect and compete with an anxiety response. However, it was more difficult to systematically pair this response with the anxiety provoking stimuli. Food consumption requires the availability of something to eat or drink, and when the food is consumed the response is not available. In contrast breathing in, or blowing on ones fingers, is a response available at any time in any situation, which appears to be a significant advantage. The procedure in case 5 may actually have been closer to a traditional shaping process using positive reinforcement than one of systematic desensitization. An additional issue in the fifth case may be the nature of the resistance to closing the car door. While A.W. did appear anxious and upset when attempts were made to close the door, his resistance may also include a control issue that goes back to power struggles with his parents. When added to his general rigidity about changing his patterns of behavior (part of his autism), his resistance to allowing a door to be closed on him may have been more complex than a simple phobic reaction. In A.W.s case, the identified phobic response was very long standing and well ingrained, whereas in the first four cases, treatment was initiated with three months of the onset of the phobic reaction. This tends to suggest that early treatment of phobias in individuals with developmental disabilities has a better prognosis than treatment of long standing phobias.
For further information, contact Dr. Howenstine at: email@example.com.
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