HITLab cognition
home projects people publications search
  back to
    projects
  overview
  papers
 

VR Therapy for Spider Phobia


Miss Muffet demonstrates she is no longer afraid of real spiders after VR therapy (a scene from SPIDERS!).

Phobics typically panic or become anxious when they encounter the object or situation that makes them afraid, even though they know the object or situation (e.g., a small house spider) is not that dangerous. Such unrealistic or excessive fears of objects or situations is a psychological disorder that can makes life miserable for years. Exposure therapy has proved effective for many different types of phobias, including spider phobia. Exposure therapy is a clinical treatment based on gradually and systematically exposing the phobic person to the feared object or situation a little at a time, starting very slowly, and calming them. Little by little their fear decreases and they become more comfortable with spiders. They will probably always be a little creeped out by spiders, but therapy can train them not to panic. After treatment, most "former phobics" start living life more fully. Success overcoming their fear can lead to increased self-confidence, which in turn often has other positive benefits.

In vivo exposure therapy, is a combination of cognitive psychology and behavioral therapy (Cognitive-Behavioral therapy, which is not Freudian). People are taught to think a little differently when they think about spiders (this is the cognitive part of the therapy, where cognition means "thinking"). In addition, during treatment phobics are deconditioned using stimulus-response learning (and unlearning). This is the Behavioral part of the treatment.

Pavlov, an early behaviorist, paired a stimulus (a bell) with the presence of food. Every time the dog heard a bell, they got some food. After doing this enough times, the dogs started to associate the bell with the food. The dogs would start salivating when they heard the bell, even if there was no food present. It is believed that spider phobia is due at least in part to a similar Stimulus-Response association. The spider, the stimulus, evokes a response, fear and anxiety. Every time the phobic runs in fear from a spider, it strengthens or at least helps maintain this association. Avoidance feed phobias.

Did you know that the Stimulus-Response conditioning can be reversed? A dog that has been conditioned to salivate when they hear a bell can be untrained! If you ring a bell without presenting food a bunch of times, pretty soon the association or link, the Stimulus-Response association between bell and food disappears, and the dog no longer salivates (or salivates much less) when they hear the bell. The behavioral therapy part of VR exposure therapy uses a similar approach to treat spider phobics. With in vivo (in life) exposure therapy, under a therapist's supervision and guidance, rather than avoiding it, the phobic slowly approaches the thing they are afraid of in the real world...the phobics initially display a rapid increase in anxiety, but if they hold their ground instead of fleeing, their fear and anxiety will actually habituate. They stop sweating, their heart rate slows down, they feel less anxiety, even though they are standing fairly near a spider! It is as if their nervous systems start to get bored with the spider. During this phase of in vivo exposure therapy when their anxiety is going down in the presence of the live spider (e.g., a tarantula in a terrarium), they are reversing the Stimulus-Response association. The stimulus-response association is sort of "cancelled out" by the new association between the presence of the spider, and a DROP in anxiety! That is, they start to associate a spider with becoming LESS anxious. In addition, the therapist explains a number of things to the patient, and helps the patient think differently about spiders. This helps the phobic think differently about their own anxiety (this is the cognitive portion of the treatment). It will be a few years before VR exposure therapy is more widely available. While it is possible to go get treated with VR right now, you may not be able to go al the way to Los Angeles to get it.

Call BrendaWiederhold, MBA, Ph.D., at the Calif School of Professional Psychology in San Diego, CA
for more information about getting VR exposure therapy (858) 623-2777, Ext. 415 Bwiederhold@cspp.edu, http://www.csppfoundation.org/vrphobia

So, if you can't find a place to get VR therapy, keep in mind that "in vivo" exposure therapy works really well too, and the Psych dept (preferably the clinical psychology, or Psychiatry dept of a University near your city can refer you to a good Cognitive-Behavioral therapist.

Claustrophobia, fear of heights, fear of spiders, fear of cats, fear of dogs, fear of driving, fear of flying, fear of public speaking are common examples of specific phobias (there are numerous other examples). Cognitive-behavioural therapy for specific phobias with in vivo exposure therapy has a VERY high success rate, and typically takes 12 hours or less, a very small amount of time, considering how long some other problems take. People with phobias rarely seek treatment for their problem! Most just limp through life avoiding the thing they are afraid of, in constant fear of being discovered. In other words, many phobics are afraid of the embarassing panic attack they will have, i.e., how bizarre they will act if they happen to run into a spider. Some are more worried about this over-reaction and the social consequences than they are about the spider itself.

In some situations, fears can be dangerous. For example, if the person nearly wrecks their car when a spider drops in their lap out of a visor, or when a patient who needs a brain scan can't go into the confined brain scanner because of claustrophobia. Over 80% of people who seek Cognitive-Behavioral therapy (e.g., in vivo exposure therapy) for their phobias no longer panic when they encounter a spider, and this typically holds true indefinitely (ie., people tend to remain cured once successfully treated).

Despite the fact that this type of treatment is so fast and effective, only a small proportion of spider phobics ever actually seek treatment for their problem. The reason is fairly obvious. Understandably, THEY DON'T WANT TO GO ANYWHERE NEAR A LIVE SPIDER, EVEN FOR THERAPY.

Virtual reality to the rescue

In collaboration with others, Barbara Rothbaum (a clinical psychologist from Emory) and Larry Hodges (a computer science expert from George Tech) were the principle investigators in the first published Journal study on using VR exposure therapy for treating a phobia (fear of heights, see http://www.cc.gatech.edu/gvu/virtual/). This was followed by a publication about using of VR for treating spider phobia by our research group at the HITLab (Carlin and Hoffman at the University of Washington in Seattle, who have recently been working with Azucena Garcia and Christina Botella from Spain, (more about this later).

Since then, down in Atlanta Georgia, Rothbaum and Hodges have had great success using VR exposure therapy to treating fear of flying, and they have ambitiously had some encouraging preliminary results treating post-traumatic stress disorder in Vietnam Vets, a disorder notoriously difficult to help (unlike phobias, which are easy to treat quickly and successfully). Hodges and Rothbaum are currently exploring the use of VR for treating fear of public speaking as well. Several of the virtual worlds developed by Hodges and Rothbaum are now commercially available for clinicians interested in using VR exposure therapy with their patients (see http://www.virtuallybetter.com/). Brenda Wiederhold has spearheaded the creation of a treatment center in Southern California. She and her colleagues have treated over 500 phobics with Hodge's virtual reality exposure therapy software. Brenda Wiederhold's group presently treats fear of heights and fear of flying (website) and probably other problems.

Albert Carlin and Hunter Hoffman, and Suzanne Weghorst published the second Journal paper on VR exposure therapy. At the suggestion of one of Al's patients, Al and Hunter extended Rothbaum and Hodges idea of using immersive virtual reality for exposure therapy to a new type of fear: spider phobia. It was actually the idea of Miss Muffet, the first patient they treated together. Prior to treatment, Miss Muffet had been clinically phobic for nearly 20 years and had acquired a number of spider-related obsessive-compulsive behaviors. She routinely fumigated her car with pesticides and smoke to get rid of spiders. She sealed all bedroom windows with duct tape each night after scanning the room for spiders. She was hypervigilant, searching for spiders wherever she went, and avoiding walkways where she might find one. After washing her clothes, she immediately put her clothing inside a sealed plastic bag, to make sure it remained free of spiders. Over the years, her condition became worse. When her fear made her hesitant to leave home (a very extreme phobia), she finally sought therapy.

Even though traditional therapy is usually effective, Miss Muffet didn't feel like she was making much progress with more traditional therapy. The possibility of using pharmaceutical anxiety treatments was being considered. Miss Muffet happened watch a Scientific American Frontiers program on PBS that featured the VR exposure therapy for "fear of heights" being done in Atlanta by Hodges and Rothbaum. Miss Muffet told Al Carlin, her therapist, that she wanted to try a virtual spider. Many if not most therapist would have scratched their heads and said "what in tarnation is that". Luckily Al Carlin knew about the HITLab, a large VR research lab at the U.W., he called us, and ended up finding Hunter Hoffman, who agreed to work with him to co-build the first VR exposure therapy world for spider phobia: SpiderWorld.


An image of what patients see (in 3-D) in SpiderWorld...their cyberhand as they grab a wiggly legged virtual tarantula.

During the 12, one hour VR therapy sessions at the U.W. Human Interface Technology laboratory (HITLab), Miss Muffet started very slowly. First she started completely across the virtual world from the virtual spider. Slowly she got a little closer, her progress closely monitored by Al and Hunter who watched what she was seeing in VR, which was also displayed to them on a compute monitor. In later sessions, after she had lost some of her fear of spiders, she was sometimes encouraged to pick up the virtual spider and/or web with her cyberhand and place it in orientations that were most anxiety provoking. Other times, the experimenter controlled the spider's movements (unexpected jumps, etc). Some virtual spiders were placed in a cupboard with a spiderweb. Other virtual spiders climbed or dropped from their thread from the ceiling to the virtual kitchen floor. Eventually, after getting used to them, Miss Muffet could tolerate holding and picking up the virtual spiders without panicking. She could pull the spider's legs off (initially this occurred accidently, and then deliberately at the experimenter's request). A large brown virtual spider with photograph-quality texture-mapped fur (made by Scott Rousseau and Ari Hollander (see www.imprintit.com), and later re-made with animations by Duff Hendrickson), and a smaller black spider and an associated 3-D web were employed (by far the best spider (just kidding) was the one Hunter made, virtual black widow spider, which reminded Miss Muffet of the spiders she saw in her nightmares described next). The black one was flawed in that it was possible to pull the virtual legs off, if one grabbed it right. This turned out to be good.

After only two, one-hour Virtual Reality exposure therapy sessions, Miss Muffet was noticing some very important progress. For example, prior to VR treatment, she had a recurring nightmare about spiders (very scary). After her second VR exposure session, she had her nightmare again that night, but it was no longer scary. In fact, in her dream, she was able to talk to the spiders for the first time, and scolded them for scaring her. "Don't feel bad lady, we scare everyone", said their cigar smoking thug leader in her dream. "Well STOP IT" she told them in her dream. The magic spell the spiders had on her was broken by her recent VR exposure therapy. Really, the truth is, the magic spell that SHE had on HERSELF was broken. VR allowed her to reverse the spell she had somehow cast on herself earlier in life, without intending to. When she came in for her third one-hour VR treatment session, there was a sparkle in her eye. She could tell she was making progress, and that gave her confidence and bravery and made her hungry to finish the job of curing herself. After several more one-hour VR sessions over several weeks (one treatment per week for three months total), she reported to us that she had had the nightmare yet again, but this time, the spiders in her dream were gone...only cobwebs remained. This routine with the dreams may only happen with this one patient, its hard to predict, but it was very interesting to us. As a psychologist interested in how the human mind works, this experience treating spider phobics with VR has been fascinating for me (Hunter).

Toward the end of Miss Muffet's therapy (e.g., after about nine, one-hour sessions), Al Carlin and Hunter started running out of new tricks to use to evoke anxiety from Miss Muffet. Miss Muffet reached out with her cyberhand in the virtual world to touch the virtual spider, but contrary to her earlier panic reactions, she had only a little anxiety now, since she had gotten used to grabbing the virtual spider.

In order for therapeutic progress to continue, Hunter and Al had to come up with some new spider behaviors or new spider-related experiences that would initially evoke an anxiety response, so they could continue to habituate Miss Muffet. They tapped a technique called mixed reality Hunter had been studying in some other VR research. One wierd thing about virtual objects is...they are typically only visual illusions, when you reach out to touch a virtual spider, your cyberhand goes right through the spider. If you reach out to touch a virtual wall, typically your virtual hand sticks right through the wall like something from a Sci Fi movie. This quality of non-solidity is interesting and fun, but it detracts from VR's realism. To give the virtual spider solidity and weight (cyberheft), Hunter rigged up a furry toy spider with a bad toupe, such that when Miss Muffet reached out to touch the virtual spider in the virtual world, her real hand simultaneously touched the furry toy spider in the real world! Although we told her it was coming, Miss Muffet was quite surprised when she had the illusion of physically touching the virtual spider. Suddenly, the virtual spider she had grown accustomed to touching without anxiety (i.e, during therapy), now evoked a huge anxiety response. But...as predicted, Miss Muffet even got used to this "mixed reality" spider. It is called mixed reality because it was part virtual ...the visual animated spider in VR, and part real, the tactile cues from the real toy spider. See the following papers for more info on Hunter's research on tactile augmentation or mixed reality at www.hitl.washington.edu/people/hunter/).

According to Miss Muffet, this extraordinary experience/illusion of physically groping the plump furry body of a Guyana bird-eating tarantula was a big turning point. She said after she had gotten over the anxiety that evoked, she was largely cured. After holding that virtual beast, an ordinary real spider in her real kitchen was not scary at all. A subsequent controlled experiment with 36 participants showed that Miss Muffet was right....exposure therapy culminating in the handling of a mixed reality spider increased therapeutic effectiveness compared to the same therapy without any mixed reality (e.g., with only virtual spiders that couldn't be physically touched). See Hoffman, Garcia-Palacios, Carlin, Furness, III, and Botella, (submitted) when it gets published.

During the course of therapy the patient could also squash the virtual spiders with a mixed-reality ping pong paddle. These interactions in VR caused her great anxiety, including trembling, sweating, and dryness of mouth, and feeling on the verge of tears.

Prior to VR treatment, the patient filled out a fear-of-spiders questionnaire. A sample of 280 undergraduate psychology students filled out the same questionnaire as a comparison group. The undergrads received no treatment and gave their ratings only once. Initially, only one undergraduate had a higher fear-of-spiders score than the patient. After 12 weekly one-hour desensitization treatments for the patient, 29% (80 students) had higher fear of spiders scores than the patient.

The results are very encouraging. Importantly, this dramatic reduction in the patient's fear of spiders is also reflected in the patient's behavior in the real world. She stopped engaging in obsessive-compulsive spider rituals, and can now interact with real spiders with moderate but manageable emotion. Her improvement is so profound that she has time for new hobbies such as camping outdoors, something she would never have dreamed of doing prior to therapy. In fact, to her amazement, the story came full circle. Miss Muffet became the star of a Scientific American Frontiers program on SPIDERS! on PBS that featured the SPIDERWORLD developed by Hoffman and Carlin. She is shown below, holding a real tarantula. (don't do this at home).

She is the first spider phobia patient to be cured using immersive VR therapy. This case study (Carlin, Hoffman and Weghorst, 1997) provides converging evidence to the growing literature showing the effectiveness of VR for medical applications. We have since treated about 20 clinical phobics with a success rate of approximately 85% at the HITlab and continue to conduct research on this interesting topic.

Rothbaum and Hodges were first, Carlin, Hoffman and Weghorst were second to publish, and...Botella and colleagues from Spain were the third group to publish a case study on using immersive VR exposure therapy for treating phobia. Interestingly, all three groups published in the journal named Behavioral Research and Therapy. Botella et al. created a VR treatment for claustrophobia, fear of enclosed spaces. Part of this treatment involves going into a fairly large virtual room. The patient controls the walls of this room, which close in on the patient in VR. As the walls close in, they make a noise like concrete scratching on concrete. Claustrophobia is a big problem for some people who need to have a brain scan but can't bear to go into the brain scanner. Botella and colleagues are also having success using VR to treat severe anorexia. Botella's active group in Spain (which includes Azucena Garcia-Palacios and several other talented clinical psychologists) is quickly becoming one of the top centers in the world for research on VR treatments for Psychological disorders.


Contacts

Hunter Hoffman, hunter(at)hitl.washington.edu

contact us      home | people | publications | search