Studying the aftereffect and changes in sensitivity to physical and mental time references using a time adaptation paradigm.

Time adaptation aftereffects occur following repeated presentation of stimuli with similar durations. This study tested whether time adaptation mechanisms align with other sensory adaptations by examining whether subsequent temporal percepts are repelled from adapted durations while demonstrating improved sensitivity. Alternative averaging hypotheses derived from Bayesian and central tendency frameworks were also investigated. Beyond the commonly employed time bisection task, this study incorporated a time production task to evaluate whether adaptation influences mental time references or remains limited to perceptual processing. Results showed that adapting to longer durations significantly reduced point of subjective equality (PSEs) in shorter-duration tasks, but not vice versa, with no consistent improvements in sensitivity observed. Support for the classical perceptual adaptation model was therefore limited. Conversely, aftereffects in the 500 ms production task shifted toward adapted durations, aligning with averaging predictions. These findings indicate that time adaptation exerts differential effects on physical versus mental time references. Moreover, temporal adaptation differs from other sensory adaptations in that it represents an integration of multimodal information rather than a modality-specific process.