Schematic depiction of the assumed processing stages in perceptual judgments of the overall intensity of time-varying visual or auditory stimuli. Equivalent sensory input (i.e., stimuli with the same duration and the same intensity variation pattern across the stimulus duration) is received auditorily (blue) or visually (orange). At the sensory stage, the stimuli are transformed into (neural) representations, and we assume that under specific conditions, the auditory and visual sensory processing results in equivalent sensory representations, so that the decision stage (evidence integration process) receives equivalent auditory and visual input. The outcome of the common, supramodal evidence integration process, which is identical for both modalities, determines the participant’s response in the 2AFC task.