The conclusion belongs to a new scientific investigation

Jun 13, 2012 12:37 GMT  ·  By

Ryerson University investigators say that many of those who suffer from insomnia also fear the dark. The connection has seldom been considered by scientists researching the root causes of insomnia.

Granted, not all of those who cannot sleep properly are afraid of the dark. What the researchers are saying is that some of them are, and that this factor has not been taken into account in other studies.

Details of the research will be presented in front of attendants gathered at the annual meeting of the Associated Professional Sleep Societies (Sleep 2012), held in Boston, PsychCentral reports.

The investigation was carried out on a number of 93 students. After analyzing a series of questionnaires that the participants had filled out, the Ryerson investigators determined that many of those who reported sleeping poorly were afraid of the dark.

The study was conducted based on anecdotal evidence that many insomniacs sleep with either their lights, or their TV sets and computers, turned on. The team decided to conduct a series of sleep lab experiments in order to determine whether that was actually the case.

“I think the most surprising part of the study is that people told us,” says Colleen Carney, PhD, a researcher and an associate professor of psychology at the Ryerson University, in Toronto, Canada.

What was even more interesting is that the study participants were young, with an average age of 22. Despite this fact, they reported relatively poor sleep habits. Experts used the Insomnia Severity Index to study the test subjects.

Researchers were able to identify 51 good sleepers and 42 poor sleepers in the group. More than 20 of the poor sleepers reported being afraid of the dark (50 percent), as opposed to 25 percent of good sleepers.

After setting up a sleep lab to resemble a bedroom, researchers exposed all participants to bursts of white noise. They then measured the speed with which each test subject blinked or otherwise reacted.

“If you are nervous, you are going to flinch. We measured the blinks, the size, and how fast. The poor sleepers tended to blink fast in the dark in response to the unexpected noise. The poor sleepers actually became more afraid,” Carney explains.

She adds that poor sleepers may become more mentally aroused when they go to bed, and the lights are turned off. This is partially what contributes to keeping them awake until the wee hours of the morning.