Visually evoked potentials at different rates of flash stimulation and concomitant perceptual changes

Relationship between the waveforms of visually evoked potentials (VEPs) and subjective temporal resolution of flash trains which lasted 1000 ms was examined under 18 kinds of stimulus rates (3-50 Hz). VEPs for flash trains were recorded from two scalp locations (Cz and Oz). Subjects' reports on flash trains were categorized into three perceptual phases (“countable”, “flickering” and “fused”) along the variable of stimulus frequency. Waveforms of VEPs were compared among the phases by correlational and filtering methods. The results were as follows: In “countable” phase (ranging 3-11 Hz) the flash train evoked a series of distinct waves, each of which highly correlated to that of VEP for a single flash. In “flickering” phase (ranging 9-45 Hz) VEPs consisted of an initial wave whose pattern resembled a single-VEP, followed by rhythmic waves synchronizing with the stimulus rate. On the other hand, in “fused” phase (ranging 30-50 Hz) VEPs showed only initial waves. These results suggested that the VEP waveform could be an index of subjective temporal resolution of flash trains

Audiology · Cognitive psychology · Electroencephalography · Flicker · Perception · Physics · Ranging · Stimulus (psychology) · Waveform · Computer Science · EEG and Brain-Computer Interfaces · Medicine · Neural dynamics and brain function · Neuroscience · Psychology · Visual perception and processing mechanisms