hide
Free keywords:
-
Abstract:
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 (s=150ms). Particularly we were interested in how the perception of these landmarks differ across vision and audition. Participants undertook a temporal order judgment task comparing the onset, peak and offset landmarks of the standard stimuli to short spike-like stimuli (s=5ms) in vision or audition. All 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 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. Discrimination threshol
ds were worse for offset judgements compared to onset or peak judgements in both modalities. The differences in perceived duration can potentially be used to explain multisensory illusions such as the flash lag effect and perceived crossmodal asynchronies. We quantitatively explain these distortion effects using models of signal processing.