Good news for the 1 in 10 Americans afflicted with chronic insomnia: According to a new study, you might be able to forgo the sleeping pills, white noise machines, warm milk, hypnosis tapes, and other slumber strategies, and simply cool your forehead to lull yourself to sleep. University of Pittsburgh sleep experts Dr. Eric Nofzinger and Dr. Daniel Buysse reported to colleagues this week that a water-circulating cooling cap helped insomniacs doze off as easily as normal sleepers. Here, a brief guide:
What is this sleeping cap like?
The 24 test subjects — 12 with natural insomnia, 12 with no sleep problems — wore soft plastic caps outfitted with tubes carrying temperature-controlled water. They slept in a lab for two nights with no cap, two nights with the caps on a "neutral" setting of about 86 degrees Fahrenheit, two more with the caps set to 72 degrees, and a final two nights with 57-degree water cooling their heads. At the higher temperatures, the caps made no difference, but on the 57-degree nights, about three-quarters of the insomniacs said they slept much better.
How much did these caps help?
The cooling caps helped insomniacs sleep better than "normal" sleepers, apparently. The insomniacs fell asleep quicker — in 13 minutes, versus 16 minutes for the control group — and spent more of the night in slow-wave sleep, which is the deepest, most restorative sleep cycle. Both groups spent an average of 89 percent of their time in bed asleep.
Why do the caps work?
Researchers already knew that insomniacs are "hyper-aroused," with a higher level of activity in their prefrontal cortex. Nofzinger and Buysse hypothesized that "frontal cerebral thermal transfer," or cooling the scalp above that part of the brain, would slow the brain's metabolism and help insomniacs sleep better. This research appears to bear that out.
When will these miracle caps be available to buy?
Nofzinger will likely bring his invention to market, but only after more testing. The researchers don't foresee any safety problems — if the cap is too cold, people will just take it off. "But before crafting your own brain-cooling device, keep in mind that the research was conducted under controlled conditions on a small sample," cautions Marianne English at Discovery News. Also, while the caps promise greater success than sleeping pills and no side effects, there are some drawbacks. "Most of us don't find it pleasurable to have a cold head — and certainly not in bed," says British sleep consultant Neil Stanley.