Autonomic nervous function after evening bright light therapy: spectral analysis of heart rate variability.
In order to investigate the effects of 5000 lx evening bright light on autonomic nervous function, a spectral analysis was used to assess heart rate variability in consecutive 5-min epochs just after 60 min of bright light therapy was given to 12 young women (range: 20-21 years of age). The study revealed that a low frequency band (LF) increased in bright light conditions (BL) in comparison with controlled conditions (CL). High frequency band (HF), LF:HF ratio and the coefficient of variance (CV R-R) were not significantly different between the two conditions. These results indicate that 5000 lx evening bright light may affect sympathetic nervous system activity in healthy women.
Sakakibara
S
S
Department of Psychiatry and Neurology, Hokkaido University School of Medicine, Sapporo, Japan. sakaki@wa2.so-net.ne.jp
Honma
H
H
Kohsaka
M
M
Fukuda
N
N
Kawai
I
I
Kobayashi
R
R
Koyama
T
T
D000328:Adult; D001143:Arousal / Q000502:physiology; D001341:Autonomic Nervous System / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D004562:Electrocardiography; D005260:Female; D005583:Fourier Analysis; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D010789:Phototherapy; D012815:Signal Processing, Computer-Assisted; D013564:Sympathetic Nervous System / Q000502:physiology