It may sound like a childish phobia, but a Toronto study has found that some people never outgrow their fear of the dark, suggesting that adult insomnia could be linked to a deeper, more innate anxiety.
For their research, scientists from Ryerson University observed the sleeping habits of a small group of Toronto college students by measuring the blink responses to sudden noise bursts in both brightly lit and dark surroundings.
While good sleepers grew accustomed to the noise, poor sleepers who admitted to being afraid of the dark were restless and more easily startled, anticipating the noises and odd bumps in the night.
The research was presented at the 26th annual meeting of the Associated Professional Sleep Societies in Boston this week.
"As treatment providers, we assume that poor sleepers become tense when the lights go out because they associate the bed with being unable to sleep. Now we're wondering how many people actually have an active and untreated phobia," said lead author Taryn Moss.
Other sleep-related studies presented at the conference ranged from research which showed that sleep deprivation can impair the brain's ability to make healthy food choices to increased risk of stroke with continuous sleep deprivation.
Meanwhile, a few expert tips on how to get over your nighttime phobia include surrounding yourself with comforting items and creating a relaxing bedtime routine with a cup of tea or hot bath.