Sleep-enhancing effects of far-infrared radiation in rats


Unrestrained male rats continuously exposed to far-infrared radiation exhibited a significant increase in slow wave sleep (SWS) during the light period but not in the dark period. The change was largely due to the elevated occurrence of SWS episodes but not to the prolongation of their duration. Paradoxical sleep was not affected throughout the observation period except for a significant decrease at the end of the dark period. Thus the far-infrared radiation exerted a sleep modulatory effect closely related to the circadian activity-rest cycle.

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Correspondence to S. Inoué.

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Honda, K., Inoué, S. Sleep-enhancing effects of far-infrared radiation in rats. Int J Biometeorol 32, 92–94 (1988).

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Key words

  • Far infrared
  • Slow wave sleep
  • Light period
  • Circadian activity-rest cycle