Study Objective: To evaluate the influence of ambient temperature on infant
s' arousability from sleep.
Design: Two groups of healthy infants with a median age of 11 weeks were re
corded polygraphically during one night: 31 infants were studied at 24 degr
eesC and 31 infants at 28 degreesC. To determine their arousal thresholds,
the infants were exposed to white noises of increasing intensities during R
EM and NREM sleep. Arousal thresholds were defined by the auditory stimuli
needed to induce arousals.
Patients or Participants: N/A
Measurements and Results: The arousal thresholds decreased across the night
in the infants sleeping at 24 degreesC (p=.017). The finding was not found
for the infants sleeping at 28 degreesC, When analyzing the arousal respon
ses according to time of the night, it was found that the auditory threshol
ds were significantly higher at 28 degreesC than at 24 degreesC between 03:
00 hr and 06:00 hr (p=.003). These findings were only seen in REM sleep.
Conclusion: High ambient temperature could add to the difficulty to arouse
from REM sleep in the late hours of the night.