Virtual reality could give people with nightmare disorder some relief from their frightening dreams.
As a sleep researcher, Patrick McNamara is hunting for new ways to treat people with nightmare disorder (also known as dream anxiety disorder). Being chased by a malevolent entity, McNamara says, is one of the most common recurring nightmares that patients report experiencing over and over again.
“Very often, people with chronic nightmares report dreaming about being chased or attacked by supernatural or demonic beings,” says McNamara, associate professor of neurology at the Boston University School of Medicine. “They can’t really see their attackers’ faces but they know their intent is to harm them. People also report being chased by animals like snakes or bears. Bears are very frequent in these types of dreams, where you’re trying to get safe, throwing up obstacles between you and the attacker, feeling like you’re about to be attacked.”
A nightmare like that might give anyone a bit of anxiety. But terrifying dreams, if they keep happening, can induce far more than just fleeting fear. McNamara says recurring nightmares can have profound long-term effects, especially for children who experience them. In the US, between half and two-thirds of children and up to 15 percent of adults have frequent nightmares.
“Recurring nightmares are really significant predictors,” he says. “They foretell mental health trouble.”
For children, that trouble can come in the form of adolescent and adult psychosis, including anxiety, depression, stress, and suicidal ideation. In adults, distressing nightmares can often be a sign of post-traumatic stress disorder (PTSD). Despite the documented clinical effects of nightmares—including distress, loss of sleep, and generalized anxiety—McNamara says we still lack easy-to-use, effective treatments for nightmare disorders.
In the mind’s eye
Imagery rehearsal therapy, the current gold standard for treatment, attempts to teach patients to replace nightmare imagery with less frightening versions. According to McNamara, success of the treatment is varied and typically short term because it relies on a person’s ability and willingness to conjure up realistic nightmare imagery in their mind’s eye, which some patients can do better than others. Naturally, most young children are even less capable of willfully controlling an imagined visual narrative than adolescents or adults.
For people who don’t experience recurring nightmares, “the hardest thing to grasp is the idea that recurring nightmares never lose their strength,” says Wesley J. Wildman, a professor of philosophy of religion. “It’s a really painful problem to have nightmares that are just as bad the hundredth time you’ve had them.”
Ultimately, Wildman says, unrelenting nightmares can make people truly afraid to go to sleep.
Switch the visuals
For the pilot study, the researchers designed moderately frightening virtual reality imagery—such as an underwater environment in which a great white shark seems to swim closer and closer to the virtual reality user—to illicit a manageable level of fear in participants. “To treat nightmare disorders, you want to expose the person to arousing and disturbing images, but you don’t want to expose them to very scary images,” McNamara says. The goal is to treat distress rather than inflict more.
They enrolled 19 study participants who reported having frequent nightmares. Using joystick and gesture controls, participants were able to modify the threatening visuals to make them less scary. McNamara says they could, for example, use a drawing tool to cover up the shark’s teeth or a sizing tool to shrink it down. Afterward, participants were also asked to write a narrative about their newly edited visual experience.
Someone might say, “When I looked [at the shark] more closely it turned out to be a great white tuna that was going to swim by me,” McNamara says. “Suddenly that tremendous force is not after you and it’s not so threatening.”
Over the course of a month, participants continued visiting McNamara’s lab twice a week to use the Oculus headset and its joystick controls to alter scary visuals and create new narratives. At each visit, they were monitored for anxiety, nightmare distress, and nightmare effects. By the conclusion of the study, participants reported significantly lower levels of all three. The results were published in the journal Dreaming.
“We think that they learn these imagery control skills and then over a couple of weeks, those skills get transferred from their conscious state into their dream state,” McNamara says.
Although the results of the pilot are exciting, McNamara says the next step is to design a double-blind clinical trial to really test the effects of virtual reality therapy. To rule out placebo therapy effects, McNamara says such a study could involve a group of participants who do virtual reality therapy and another group of participants who do standard imagery rehearsal therapy.
“The most exciting thing about this is the potential to bring this to kids suffering from nightmares,” McNamara says. “Kids are fantastic with adopting technology, and if we can treat their nightmares earlier, we might slow down or prevent conversion into psychosis. That could save lives.”
Funding for the pilot project came from the Center for Mind and Culture and the Virginia Modeling, Analysis & Simulation Center.
Source: Boston University