RELATIONSHIP BETWEEN SLEEP STAGES AND SHORT-TERM CHANGES IN RECTAL TEMPERATURE IN HUMANS

Sixteen volunteers have been studied during 3-4 control nights and eig ht of these subjects again during four successive sleeps on 30-h ''day s''. The experiments took place in a comfortable environment provided by an isolation chamber. Rectal temperature and the sleep EEG were mea sured throughout. The relationship between sleep stages, particularly SWS and REM sleep, and short-term changes in rectal temperature has be en investigated during both protocols. Care was taken to correct for o r remove those temperature changes that could be attributed to circadi an rhythmicity or the effects of loss of masking due to being awake. R esults showed that there was a small but significant effect of sleep s tages, with SWS producing a fall and REM sleep a rise in rectal temper ature after a delay of about 30-48 minutes. It is concluded that such spontaneous changes in sleeping subjects accord with the results of ot her studies which indicate that thermoregulatory reflexes to hot or co ld stimuli alter in different sleep stages.