Change biases identify the features that drive time perception

Abstract

[This paper has not been peer reviewed. Please do not copy or cite without author's permission.] Time perception is malleable, and the perceived duration of stimuli can be strongly affected by the sensory response they evoke. Such ‘temporal illusions’ provide a window on how different sensory systems contribute to our sense of time. Evidence suggests that the sensory response to different features affects time perception to different extents, mediated by the level of arousal or surprise that they evoke. This, however, makes it difficult to disentangle effects of the sensory response itself from the derived arousal or surprise effects. Here, we demonstrate that time perception is differentially affected by different stimulus features when arousal and surprise are kept constant. In four temporal discrimination experiments, participants judged the duration of an interval marked by two briefly presented visual markers. Markers either repeated or changed along one of six feature dimensions, in a manner fully predictable to participants. Repetitions and changes would modulate sensory response magnitudes due to neural repetition suppression. Results showed that intervals were perceived as longer when markers changed in location, size or numerosity. Conversely, changes in face identity, orientation or luminance did not affect time perception. These results point to neural and functional selectivity in the way different stimulus features affect time perception.