A sense of time: Non-linear distortions in perceived time across the senses

Perceived time is not veridical but distorted and differs across the senses. Here we ask, which points in the perception of a temporal event contribute most significantly to these multisensory distortions? To this end, we investigated perceptual estimates of temporal landmarks (onset, peak amplitude, and offset) for a Gaussian standard signal. Furthermore, we identified that the perception of these landmarks differ across vision and audition. Participants were asked to compare the onset, peak and offset landmarks of the standard long visual/auditory stimuli to short spike-like stimuli in vision or audition. Four combinations were tested: V–v, A–a, V–a, A–v. Results demonstrate that the visual as compared to auditory standard stimuli were perceived as shorter. More interestingly, we found a compression in the perceived duration for onset-peak intervals compared to peak-offset intervals. This compression effect was more pronounced in the visual modality. We compared the distortion results to those obtained with a second signal envelope type and demonstrated the same pattern of distortions for this temporally more veridical. However, the delayed onset, advanced peak and offset were the same across the two signals. The differences in perceived duration can potentially be used to explain multisensory illusions such as the flash lag effect and perceived crossmodal asynchronies. Such distortions can be accounted for by simulated neural response functions