If you're sleep deprived, you're more likely to be stressed out and negative, according to a new study.

Richard Comse, a patient at St. Barnabas Hospital's sleep center, agrees. He recently visited the hospital to be fitted for a continuous positive airway pressure, or CPAP, machine to help his sleep apnea.

Comse, 48, believes his problems started after he was involved in a major motorcycle accident in 2012.

"I went through hell," he says. "I mean, I didn't understand my life anymore and people telling me that I was giving up, that I was feeling sorry for myself." Turns out, Comse may have been right.

A study published this week by the journal Cognitive Therapy and Research links lack of sleep with increased stress and bad thoughts. The study grabbed the attention of Dr. Daniel Erichsen, director of the sleep center.

"What this new study shows is that when you sleep also matters," he says. "It appears that going to bed later is detrimental in terms of your mood."

The study, which involved Binghamton University students, found that people with later bedtimes continuously experience negative thinking, compared with people who go to bed earlier.

"Adjust your wake-up time first," Dr. Erichsen advises patients. "Wake up a little earlier and then your bedtime will fall into place." He also recommends using bedrooms only for sleeping.

Doctors believe that following these few tips can help improve a person's mood in as little as a week.