Subjective frequency in flicker perception.

The discrepancy between the actual flicker frequency and the perceived rate was investigated. We tried to quantify the subjective rate of successive visual flicker by matching it with a second stimulus, the audio flutter. The wave form of each stimulus employed in the present study was sinusoidal. The auditory stimulus employed as a reference was a pure tone which was frequency-modulated by a sine wave. The perceived rate of flicker increases approximately in direct proportion to the frequency presented when target size is small and tends to be lower than the actual rate when target size is large. Perceived rate never exceeds approximately 10 Hz regardless of the presented flicker frequency or the luminance of the target. These tendencies are observed commonly in the fovea and in the periphery of the retina.