Word: circadian
(lookup in dictionary)
(lookup stats)
Dates: during 1965-1965
Sort By: most recent first
(reverse)
Adrenal Tides. Such time-zone crossings foul up man's daily physiological cycles, the "circadian rhythms"* that are still one of nature's deepest mysteries. No matter where he lives on earth, man becomes adjusted to daily cycles of activity and sleep that correspond roughly to the cycles of light and dark. But it is by no means a simple matter of day and night. Man seems to have both wakefulness and sleepiness centers, and the two interact-one switching off the other. Man also has temperature cycles; if he stays up late enough, he will feel chilly...
...days of a long-awaited European or Hong Kong holiday, but without scientific testing there was no way to know whether the complaints reflected changes in longitude or overindulgence in food and liquor on the plane. What Hauty wanted now was reliable data that might help him predict circadian effects on pilots' performance during long jet flights, on astronauts whose "days" get shortened to less than 100 minutes, and finally, on weary passengers...