Expected events dilate subjective duration in the auditory modality: Effects of predictability and expectation on time perception.

In timing research, repeated stimuli have been shown to have a shortening effect on time perception compared to novel stimuli. This finding had been attributed to repeated stimuli being more expected and, thus, less arousing and/or attended, or eliciting less neuronal activation due to repetition suppression, which results in temporal underestimation. However, more recent studies in the visual domain that disentangled effects of repetition and expectation suggest a more nuanced interpretation. In these studies, repetition led to temporal contraction while expectation caused subjective dilation of time. It was argued that expectations increase the perceptual strength of the stimulus, which leads to temporal overestimation, while repetitions reduce perceptual strength, which then leads to temporal underestimation. In the present study, we sought to further elaborate on these findings using auditory stimuli. In Experiment 1, we used an implicit method to induce expectation and manipulated the probability of stimulus repetition block-wise in a two-stimulus paradigm with auditory tones. Our findings were in line with the recent findings. When repetitions were less frequent, that is, less expected, we found clear evidence for perceived temporal contraction of repetitions. In contrast, when repetitions were more expected, the shortening effect of stimulus repetition on subjective duration disappeared. In Experiment 2, participants explicitly generated expectations about an upcoming tone in a temporal bisection paradigm. In trials, where expectations were fulfilled, presentation durations were perceived longer compared to trials with unfulfilled expectations. Our findings suggest that factors that increase the perceptual strength of a stimulus contribute to subjective temporal dilation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).