A late bedtime is associated with lower perceived control of obsessive thoughts, according to new research from Binghamton University, State University of New York.

Binghamton University Professor of Psychology Meredith E. Coles and former graduate student Jessica Schubert (now at University of Michigan Medical School) monitored twenty individuals diagnosed with OCD and ten individuals endorsing subthreshold OCD symptoms during one week of sleep. Participants completed sleep diaries and daily ratings of perceived degree of control over obsessive thoughts and ritualized behaviors. The researchers found that previous night's bedtime significantly predicted participants' perceived ability to control their obsessive thoughts and compulsive behavior on the subsequent day.

"We're really interested in how this kind of unusual timing of sleep might affect cognitive functioning," said Schubert. "One possibility is impulse control. It might be that something about shifting the timing of your sleep might reduce your ability to control your thoughts and your behaviors, so it might make it more likely that you're going to have a hard time dismissing intrusive thoughts characteristic of obsessions, and it might make it more difficult for you to refrain from compulsive behaviors that are designed to reduce the anxiety caused by obsessive thoughts."

On average participants in the study went to bed around 12:30 at night. Patients who met criteria for delayed sleep phase disorder, about 40% of the sample, went to bed around 3 a.m.

"I always knew you were supposed to get eight hours of sleep, but I was never told it matters when you do it," said Coles. "It's been striking to me that this difference seems to be very specific to the circadian component of when you sleep. That we find that there are specific negative consequences of sleeping at the wrong times, that's something to educate the public about."

The researchers are interested in exploring this phenomenon further. Coles plans on collecting pilot data using lightboxes to shift people's bedtimes. "It's one of our first efforts to actually shift their bedtimes and see if it reduces their OCD symptoms, and if this improves their ability to resist those intrusive thoughts and not develop compulsions in response to them."