Hozumi Matsubara

Bright light treatment for sleep–wake disturbances in aged individuals with dementia

Treatment using bright light exposure was carried out on six aged subjects with dementia in two nursing homes. Sleep logs were recorded by the staff. Bright light treatment was applied in the late morning every day. The %sleep in the lights‐out period and/or the %wake in daytime increased in three subjects. In the other three subjects, sleep onset time was advanced. In all subjects abnormal behavior episodes around the lights‐out time tended to be reduced. These results suggest that bright light treatment is effective in improving the sleep–wake disturbances of aged individuals with dementia.

SLEEP IMPROVEMENT BY LIGHT IN A DEMENTED AGED INDIVIDUAL

Abstract We administered daily morning bright light exposure in two separate periods to a demented aged subject in a nursing home and analyzed the sleep pattern changes from the sleep diary over 6 months. In the first light exposure period, the ratio of sleep time in night hours increased and maintained a higher value throughout the period than the previous baseline. After stopping the light exposure, the sleep pattern of the subject deteriorated. Resuming the light exposure reproduced similar sleep pattern changes. These results suggest that morning bright light exposure provides a better environment for aged persons to maintain a regular sleep‐wake pattern.

Effects of moderately bright light on subjective evaluations in healthy elderly women

Eight healthy elderly women aged 56–72 years (mean age: 67.4 years) participated in this study. They were exposed to moderately bright light (1000 lux) for 1 h in the morning every 6 days in their homes. Moderately bright light improved self evaluations for alertness, mood, motivation, happiness, refreshment, concentration and appetite after the second exposure to the light. Sleep maintenance, anxiety and integrated sleep feeling also improved after the fourth exposure to the light. The phase of rectal temperature rhythm did not change in a moderately bright light condition. These results suggest that bright light influences sleep quality and self evaluations without changing the biological rhythm phase.

Effects of short duration morning bright light in healthy elderly. II:Sleep and motor activity

Abstract Subjective sleep feelings and motor activity were measured in seven healthy elderly subjects for 6 days. The subjects were exposed to bright light (6000 lux) for 30 min in the morning or instructed to sit in front of a desktop lighting device without light. The average level of motor activity during the night was significantly decreased in the bright light condition, compared with the controlled condition. However, daytime motor activity did not show significant differences between the two conditions. From these findings, even a short duration of morning bright light is effective in maintaining sleep without changing daytime activity.

Effects of short duration morning bright light in healthy elderly subjects. I:Subjective feeling and ophthalmological examinations

Abstract Seven aged subjects aged 61–78 years were exposed to 6000 lx bright light for 30 min during morning hours at their homes for 1 week. Visual analog scale was recorded before bedtime and after rising to assess subjective feelings. Ophthalmological examinations were made before and after light exposure, to exclude pre‐existing ocular disorders and to detect ocular damage. Furthermore, ocular fatigue was self‐evaluated immediately before and after exposure. Visual analog scale results indicated that alertness reduced significantly before bedtime. Ophthalmological abnormalities were not found after exposure. These findings suggest that short duration morning bright light exposure reduces night‐time vigilance.