Effect of Temporal Frequency Spectra of Flicker on Time Perception: Behavioral Testing and Simulations Using a Striatal Beat Frequency Model

Abstract

When a visually presented stimulus flickers, the perceived stimulus duration exceeds the actual duration. This effect is called ‘time dilation’. On the basis of recent electrophysiological findings, we hypothesized that this flicker induced time dilation is caused by distortions of the internal clock, which is composed of many oscillators with many intrinsic vibration frequencies. To examine this hypothesis, we conducted behavioral experiments and a neural simulation. In the behavioral experiments, we measured flicker induced time dilation at various flicker frequencies. The stimulus was either a steadily presented patch or a flickering patch. The temporal frequency spectrum of the flickering patch was either single peaked at 10.9, 15, or 30 Hz, peaked with a narrow band at 8–12 or 12–16 Hz, or peaked with broad band at 4–30 Hz. Time dilation was observed with 10.9 Hz, 15 Hz, 30 Hz, or 8–12 Hz flickers, but not with 12–16 Hz or 4–30 Hz flickers. These results indicate that both the peak frequency and the width of the frequency distribution contribute to time dilation. To explain our behavioral results in the context of a physiological model, we proposed a model that combined the Striatal Beat Frequency Model and neural entrainment. The simulation successfully predicted the effect of flicker frequency locality and frequency specificity on time dilation, as observed in the behavioral experiments.