Mars' Sleep Cycle Study May Help Earthlings

(HealthDay News) -- By synchronizing people to the Martian day, U.S. researchers are demonstrating the flexibility of the human biological clock.

The study might help further research into sleep woes, said researchers in the division of sleep medicine at Brigham and Women's Hospital in Boston.

"Understanding how our biological clock can be adjusted is a critical step in developing therapy for circadian rhythm sleep disorders, which disturb sleep at night and compromise daytime cognitive functioning," lead author Frank A. J. L. Scheer, associate director of the Medical Chronobiology Program at BWH, said in a prepared statement.

His team was able to synchronized volunteers' biological clocks to the 24.65-hour day of Mars and to the 23.5-hour day often experienced by astronauts in low orbit around the Earth.

The researchers also found that synchronizing with the Martian clock resulted in long-term changes to the circadian period of the volunteers' biological clock. This showed, for the first time, flexibility in the this system in humans, the study authors said.

For this study, seven young men spent 73 days in a controlled environment without any time cues, other than controlled light/dark conditions.

According to the researchers, the findings could prove important in treating circadian rhythm sleep disorders (such as those caused by jet lag and shift work) and in preparing humans for space exploration.

The study is in the Aug. 8 issue of the journal Public Library of Science ONE.

More information

The U.S. National Institute of Mental Health has more about the biological clock.