No abstract

Five healthy adult women aged 20 to 28 had 12-15 polysomnographic recordings, as well as daily basal body temperature and multiple LH, FSH, estrogen and progesterone measurements taken during a single menstrual cycle. Sleep stages were scored both visually and with a spindle and delta-wave, real-time, automatic analysing system. A cubic growth-curve model showed that the frequency of sleep spindles changed markedly over the menstrual cycle: spindle frequency was lowest about 18 days before onset of menses and highest 3 days before onset of menses. Slow waves did not change. The percentages of Stage 1 and REM sleep showed small changes during the menstrual cycle, and other parameters of visually scored sleep showed no tendency to change. Spindle frequency may reflect the effects of sex hormones on the reticular thalamic nucleus and may be a quantitative marker of premenstrual sleep disturbances.

Twenty-five young people (Y group), three elderly people and seven people with various sleep disorders (SD group) kept a sleep log for 2-7 days, and their wrist-activity was monitored simultaneously. The sensitivity and specificity of the sleep log, and the ratio of agreement between the sleep log and actigraphic sleep-wake state were calculated. The sensitivity and specificity in Y group were 87.93 ± 6.49% and 96.51 ± 2.37%, respectively. The sensitivity in SD group was significantly lower than in Y group. Even in Y group one-hour agreement ratios dropped during the sleep onset period.

The subjects were eight men of the Japanese Antarctic Research Expedition (average age 35.8 years), and 10 healthy people living around Kofu, Japan (28.9 years). They completed a sleep log for 12 to 18 months, and the sleep-wake state was scored in 10-min epochs. Q 24 values calculated by c 2 periodgram were low in the Antarctic midwinter. This means that there was difficulty in synchronizing to a 24-h period in the Antarctic midwinter. In Antarctica, sleep onset and offset times were delayed mostly in the midwinter. In Japan, sleep offset time was delayed mostly around the winter solstice.

Summary Photic stimulation from 0.5 to 20cps flickers was given on 7 cases of portal‐systemic encephalopathy. The triphasic waves were increased by the stimulation (mostly appearing synchronously with 2.0–3.5 cps of flicker) in all cases at least more than once in repeated EEG examinations. Bemegride activation was performed on three cases who had theta and alpha background activity with very poor delta waves. The triphasic waves increased in number remarkably in two cases and poorly in one. Based on these reactions to the photic stimulation and bemegride activation, it was suggested that the triphasic waves and epileptic discharges might have some similar mechanism in their production. (This study was presented at 18th annual meeting of Japan EEG Society, 1969