Change biases identify the features that drive time perception

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 were presented with empty intervals (1.25 s-2.25 s) marked by two briefly presented visual marker stimuli, and judged whether the duration was longer or shorter than a 1.75 s reference. 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.Public Significance StatementThe neural sensory response evoked by a stimulus can affect its perceived duration. When a stimulus repeats, sensory neurons will have an attenuated response, which makes the stimulus seem to last shorter than when a stimulus changes. This study uses this observation to disseminate the relation between time perception and sensory responses to different visual features, and demonstrates that the different features that make up a stimulus affect its perceived duration.