A new study shows that people with primary insomnia may be able to find relief by wearing a cap that cools the brain during sleep. The findings were presented last week at SLEEP 2011, the 25th Anniversary Meeting of the Associated Professional Sleep Societies LLC, in Minneapolis.

According to the researchers, a reduction in metabolism in the brain’s frontal cortex occurs while falling asleep and is associated with restorative sleep. Insomnia, however, is associated with increased metabolism in this same brain region. One way to reduce cerebral metabolic activity is to use frontal cerebral thermal transfer to cool the brain—a process known as “cerebral hypothermia.”

Results show that there were linear effects of all-night thermal transfer intensities on sleep latency and sleep efficiency. The time that it took subjects with primary insomnia to fall asleep (13 minutes) and the percentage of time in bed that they slept (89%) during treatment at the maximal cooling intensity were similar to those of healthy controls (16 minutes and 89%).

“The most significant finding from this study is that we can have a beneficial impact on the sleep of insomnia patients via a safe, nonpharmaceutical mechanism that can be made widely available for home use by insomnia sufferers,” said Eric Nofzinger, MD, professor and director of the Sleep Neuroimaging Research Program at the University of Pittsburgh School of Medicine. “The finding of a linear dose response effect of the treatment implies a direct beneficial impact on the neurobiology of insomnia that can improve the sleep of insomnia patients.”

The study screened 110 people, enrolling 12 with primary insomnia and 12 healthy, age- and gender-matched controls. Participants with insomnia had an average age of about 45 years, and nine of the 12 subjects were women.

Participants received all-night front cerebral thermal transfer by wearing a soft plastic cap on their head. The cap contained tubes that were filled with circulating water. The effectiveness of varying thermal transfer intensities was investigated by implementing multiple conditions: no cooling cap, and cooling cap with either neutral, moderate, or maximal cooling intensity.