Norwegian Studies Indicate How to Reset ‘Body Clock’ : Arctic Scientists May Unlock the Secret of Insomnia

Scientists in this Arctic city, where midwinter darkness affects the sleeping habits of up to one-quarter of the population, say they may have unlocked some of the secrets of insomnia and pointed the way to a cure.

Research elsewhere in the world has pinpointed the hormone melatonin as playing a vital role in sleep, but a Norwegian biochemist believes his team may be close to being able to alter the human “body clock” to eliminate sleepless nights.

Scientists operating a “sleep clinic” here have found that large doses of bright light help produce melatonin, secreted from a gland near the brain.

Thormar Hansen, who has set up the laboratory linked to the world’s most northerly university here, said in an interview that further research is needed but that there is strong evidence to show that sleeping patterns can be altered by adjusting the time of day when melatonin is produced.

Melatonin has a hypnotic effect and is believed to be a key factor in falling asleep. Hansen, a biochemist, said research shows maximum secretion of the hormone is at 2 a.m., while the brain begins producing it at about 11 p.m., when most people are falling asleep.

Local conditions have favored Hansen’s research. He said the darkness that descends upon Norway between November and March is known to play havoc with sleeping habits, and the 24 hours of daylight that occur in summer also cause problems.

No reliable figures are available for numbers suffering from insomnia, but statistics show that 20% to 25% of north Norwegians are victims. Hansen said the figure for the rest of the world is unlikely to be more than 2%.

American research has already gone a long way toward proving that midwinter darkness can upset the body’s clock, which is set by daylight. Artificially regulating the flow of melatonin could correct such imbalances.

Tests in the United States showed that autumn and winter in parts of the world with above-average hours of daylight can induce depression and sleeplessness that appear to be connected with melatonin-production levels.

Insomniacs in Tromso were tested last year with half-hourlong bursts of artificial light containing virtually all the qualities of natural sunlight. The tests, which took place early in the morning, lasted five days. Hansen said the results were impressive.

“We saw a significant improvement in sleep latency, that is, the time that elapses between going to bed and falling asleep,” he said.

Patients also said they had lost the feeling of total exhaustion that insomniacs usually suffer the morning after struggling to sleep all night. Instead, they found they were sleepier in the late evening, when they wanted to be.

Hansen said many of the test results were subjective, but he hopes that more exhaustive analysis being carried out this year, involving blood tests to monitor melatonin levels, will finally prove that the hormone is vital to a good night’s sleep.

“Some people call melatonin a sleep inducer, but I prefer to refer to it as a rhythm-setting hormone of the human clock,” he said.

Although insomnia has been at the center of Hansen’s studies for about 10 years, his research and biochemical background have also led him into studies of links between drugs and their effects on sleep and mental behavior.

The importance of certain types of sleep has been underlined by Hansen’s work. Tests show that if a person is deprived of “rapid eye movement,” the few moments when dreams occur, he is left feeling that he has not slept at all.