|TNS harnesses current from a 9-volt battery to
power a patch that sends a low-level current to
cranial nerves that run through the forehead.
Photo: Reed Hutchinson
An average of 30 years had passed since the traumatic events that had left them depressed, anxious, irritable, hypervigilant, unable to sleep well and prone to nightmares. But for 12 people who were involved in a UCLA-led study — survivors of rape, car accidents, domestic abuse and other traumas — an unobtrusive patch on the forehead provided significant relief from post-traumatic stress (PTS).
“We’re talking about patients for whom illness had almost become a way of life,” says Andrew Leuchter, MD (RES ’84, FEL ’86), director of the neuromodulation division at the Jane and Terry Semel Institute for Neuroscience and Human Behavior at UCLA. “Yet, they were coming in and saying, ‘For the first time in years, I slept through the night,’ or, ‘My nightmares are gone.’ The effect was extraordinarily powerful.”
The research revealed the first evidence that trigeminal nerve stimulation, or TNS, holds promise for treating chronic PTS. “Most patients with PTS do get some benefit from existing treatments, but the great majority still have symptoms and suffer for years from those symptoms,” Dr. Leuchter says. “This could be a breakthrough for patients who have not been helped adequately by existing treatments.”
TNS is a new form of neuromodulation, a class of treatment in which external energy sources are used to make subtle adjustments to the brain’s electrical wiring to drug-resistant neurological and psychiatric disorders. While the patient sleeps, a patch, powered by a 9-volt battery, sends a low-level current to cranial nerves through the forehead to signal parts of the brain that help regulate mood, behavior and cognition, including the amygdala and medial prefrontal cortex, as well as the autonomic nervous system. Prior research has shown abnormal activity in those areas of the brains of PTS sufferers.
The researchers recruited people with chronic PTS and severe depression who were being treated with psychotherapy, medication or both. While continuing their conventional treatment, the volunteers wore the patch while they slept. Before and after the eight-week study, the study subjects completed questionnaires about the severity of their symptoms and the extent to which the disorders affected their work, parenting and socializing. The severity of participants’ PTS symptoms dropped an average of more than 30 percent, and the severity of their depression dropped an average of more than 50 percent. In fact, for one-quarter of the study subjects, PTS symptoms went into remission.
“Trigeminal Nerve Stimulation for Comorbid Posttraumatic Stress Disorder and Major Depressive Disorder,” Neuromodulation: Technology at the Neural Interface, January 28, 2016