Healthy persons who increase their sleeping hours improve their daytime alertness and experience a reduction in pain sensitivity, a recent study showed. This study was conducted at the Sleep Disorders and Research Center of the Henry Ford Hospital in Detroit. Led by Timothy A. Roehrs, PhD, the researchers worked on eighteen healthy and pain-free volunteers who experience daytime sleepiness. Randomly, these sleepy volunteers were separately assigned either to four nights of keeping their usual sleeping time or to an extended period of up to ten hours in bed every night. No sleep aids were used in the study.

The multiple sleep latency test, a tool for measuring how long it takes for a person to fall asleep, was employed to assess daytime sleepiness. The pain sensitivity of each of the subjects was gauged via a finger withdrawal latency pain test based on a radiant heat stimulus. The objective of the study was to determine whether daytime alertness will be increased and pain sensitivity will be reduced in the subjects having an extended night bedtime.

On a typical day, it takes an average of below eight minutes in the eighteen subjects in the study to fall asleep. They were randomly divided into two groups. The first group had an extended bedtime of ten hours for four nights. The second group who can’t sleep longer, on the other hand, kept their regular short bedtime hours also for four nights. All of the subjects were tested to determine each of their sleepiness level. This test was administered four times each day at different hours—10 a.m., 12 p.m., 2 p.m., and 4 p.m. Twice a day, the volunteer subjects were also subjected to a pain sensitivity test using a laser device which increases in heat intensity.

The average sleeping time of the first group came out 1.8 hours more than that of the second group which kept their regular sleeping hours. It also took longer for those in the second group to fall asleep as verified in the four sleepiness assessments each day, meaning they were less sleepy than the subjects in the second group which observed their normal sleep schedule. The pain sensitivity test also showed that the volunteers in the first group with extra bedtime took longer in pulling away their fingers from the laser heat stimulus.

What this test showed, the Roehrs said, is that the threshold of pain in the first group is higher than that of those in the second group. He added that theirs is the first study to demonstrate that extending night bedtime results not only in reduced daytime sleepiness but also in higher pain tolerance.

Author's Bio: 

Mike Smith writes on various topics including sleep and insomnia, health advice and health. He is published on more than 300 websites including: