Über kennzeichnende Unterschiede im Wert verschiedener Phasen typischer EEG-Potentiale des Menschen für die Aktivierung des EEG durch Augenbelichtungen

Summary

Instead of a constant repetitive stimulation brain waves themselves were used to stimulate with the purpose to set the cortical excitation by light flashes in determinated wavesphases.

The relation between phase of the potential and resulting frequency of self-stimulation is investigated. If under due consideration of retinocortical time an excitation reaches the cortex 5–10 msec after the negative maximum of an α-wave, a saltatory frequency change from about 9 to 15 c/sec resulted. Furthermore the pattern is continuous till to the equivalent position of the following cycles. The point of saltation corresponds with the beginning of the supernormal phase of an evoked potential, suggesting the same kind of process as a basis of these phenomenons. The behaviour described was only exhibited by waves up to 16 c/sec. Reactions above 17 c/sec (β-waves) exhibited a different kind of distribution. They accumulated in a phase-segment with α-potentials of only slow frequency and exhibited no saltation of frequency.

This is considered to be a method leading to direct qualitative though restricted statements about the relationships between characteristic EEG-potentials and stimulation by sensory stimuli.