Yasushi Tsukahara

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The suppressive effect of sunglasses upon photoparoxysmal responses (PPRs) elicited by 15-Hz flicker stimuli with a low luminance of nearly 10 nits was studied in eight patients with photosensitive epilepsy. Using three commercially available sunglasses of neutral density (ND), blue, and brown, the influence upon generalized PPRs elicited by a flickering(More)
Using the visual stimulator, the effect of color on the photoconvulsive response (PCR) was studied in 14 photosensitive patients. When stimuli of 15 c/sec flickers of white, red, yellow, green and blue light of 20 cd/m2 were given to the subjects, generalized PCRs were provoked only by the red-flicker. These PCRs were all inhibited by blue light of 1.9(More)
On the evening of 16 December 1997 approximately 700 people around the nation (mostly children) were rushed to hospitals and treated for seizure symptoms. The youngsters had been watching the vastly popular TV animated cartoon series Pocket Monsters (Pokemon). We designated those individuals as a main group, who presumably had simultaneous occurrence of(More)
OBJECTIVE We performed this study to elucidate the roles of stimulus spatial frequency and visual field in eliciting generalized photoparoxysmal response (PPR) by flickering dot pattern (FDP) stimulation. METHODS We studied 20 photosensitive epilepsy patients, aged 7-48 years (means +/- SD, 21.4+/-11.7 years), producing a 20 Hz FDP stimulation with a(More)
The correlation between the effects of zopiclone (ZPC), a nonbenzodiazepine hypnotic drug, on sleep polysomnograms and on daytime EEGs was examined in 12 healthy adult male volunteers. Sleep polysomnograms were recorded after a single oral administration of ZPC 10 mg or placebo according to the double-blind crossover method. Daytime EEGs were recorded after(More)
The effects of diazepam on the EEG were studied by means of EEG topographic mapping, using recordings with four different references. Subjects were ten healthy, right-handed, male volunteers aged 21-25 years. Double-blind crossover trials with a single oral dose of 10 mg diazepam and placebo controls were conducted in random sequence at intervals of one(More)
We studied 21 photosensitive persons aged 9-40 years (mean +/- SD: 20.9 +/- 9.3 years), producing a flickering dot pattern stimulation with a strobo-filter with 22 nits luminance. Five dot patterns (spatial frequencies of 0.5-4.9 c/deg) were used. Using 6 flicker frequencies from 5 to 30 Hz, we gave flickering dot pattern stimuli with each dot pattern, for(More)
Zopiclone is a cyclopyrrolone derivative which possesses hypnotic activity. This drug is known to increase the slow sleep stage compared to benzodiazepines in polysomnography. The subjects were 10 right-handed healthy male volunteers aged 21-23 years. Double-blind crossover trials with placebo control were conducted in a random sequence at intervals of 1(More)
PURPOSE In a previous study we demonstrated that the progression of the disease retinitis pigmentosa (RP) can be readily monitored by the mean deviation (MD) measured by Humphrey central 10-2 perimetry, which assesses the sensitivity distribution in the macular area in eyes affected by RP. In the present study, we investigated whether the 10 degrees(More)
Power spectrum of photic driving elicited by 5/sec flickering dot pattern (FDP) and 5/sec red flicker (RF) stimuli was investigated in 137 psychiatric outpatients. They consisted of 61 adults (33 males and 28 females) from 20 to 44 years of age, 55 preseniles (25 males and 30 females) from 45 to 64 years and 21 seniles (9 males and 12 females) over 65 years(More)