Insomnia may be caused by a fear of darkness, according to a new study by the Associated Professional Sleep Societies.
The small research study found that 50 percent of adults who reported sleep problems also admitted to being scared of the dark, according to MSNBC.
"People often think it’s a juvenile fear, and adults don’t usually want to admit that they’re even afraid of the dark," Colleen Carney, an associate professor at Ryerson University in Toronto and lead author of the study, told MSNBC.
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According to ABC, the research group studied nearly 100 college students who were either good sleepers or poor sleepers. They monitored small twitches in eye muscles during sleep while exposing the subjects to unexpected bursts of sound both with the lights on and off.
The poor sleepers were more easily startled by the burst of noise, and their reactions were exaggerated by darkness, with participants becoming more anxious as the night progressed. On the other hand, the good sleepers seemingly became accustomed to the noises and eventually stopped reacting to it.
Insomnia affects about 30 percent of adults within a given year, according to the American Academy of Sleep Medicine. Up to 15 percent say they have chronic insomnia.
Carney said the good news coming from the study is that the fear of darkness is very easy to treat with the use of exposure therapy. “We can get people accustomed to the dark so they won't have that added anxiety that contributes to their insomnia," Carney said.