Generalized Paroxysmal Discharges Induced by Visual Stimuli and Eye Movements

Influence of pattern and red color on the photoconvulsive response and the photic driving.

“…Takahashi and Tsukahara (1976) reported that red flicker shows the most significant activation of photoconvulsive responses among the stimuli of 15 Hz flickering colored light. Furthermore, by use of a visual stimulator, it has been demonstrated that 15 Hz red flicker among various visual stimuli shows the strongest activation of photoconvulsive responses (Takahashi and Tsukahara 1974, 1975). Based on these findings, the red filter was used in this study as mentioned in the introduction.…”

“…The patterns used for method 1 were dot and grating patterns (Takahashi and Tsukahara 1975) printed on plastic plates (DU-22, GO-22, Nihon Kohden, respectively) ; the diameter of a single dot and the width of a line were both 2.0 mm (0.27 degrees). Putting each pattern on a stroboscope reduced the luminosity of IPS to 1/8.…”

“…After 2 to 3 min dark adaptation, the subject looked at the central regions of a tangent screen set at 25 cm from the eyes through a small window and the stimuli were projected onto the screen (252<25 cm). When dot and grating patterns (Takahashi and Tsukahara 1975) were projected onto the screen, the visual angles of a single dot and a line were 1.33 and 0.41 degrees, respectively. The brightness of each of the visual stimuli on the screen was 20 cd/m2 (in the case of pattern, brightness of the ground).…”

Power spectral analysis of photic driving elicited by flickering dot pattern and red flicker stimuli in adult psychiatric outpatients - With special reference to age and gender.

“…Our findings suggest that the visual system of older female patients is very responsive not only to patterned stimuli but also to red flicker stimulation. photic driving ; geometric pattern ; red color ; aging; gender Within a span of four decades since the first report by Walter et al (1946) appeared, intermittent photic stimulation by the use of stroboscopic white light (to be abbreviated as IPS, hereafter) has been the most common method for eliciting photic driving in a routine EEG examination.Studies dealing with the activation of photoconvulsive response have revealed that visual simuli of flickering geometric pattern (Jeavons et al 1972;Engel 1974;Panayiotopoulos 1974;Takahashi and Tsukahara 1975) and red flicker (Carterette and Symmes 1952;Takahashi and Tsukahara 1976) were more effective in provoking photoconvulsive response than IPS. Application of flickering dot pattern and red flicker stimuli…”

“…Studies dealing with the activation of photoconvulsive response have revealed that visual simuli of flickering geometric pattern (Jeavons et al 1972;Engel 1974;Panayiotopoulos 1974;Takahashi and Tsukahara 1975) and red flicker (Carterette and Symmes 1952;Takahashi and Tsukahara 1976) were more effective in provoking photoconvulsive response than IPS. Application of flickering dot pattern and red flicker stimuli…”