Neural responses of Interval Judgment in the Tritone Paradox

The Tritone Paradox is an auditory illusion in which a sequence of two complex tones is perceived as either ascending or descending, depending on the individual. It presents an interesting phenomenon for investigating pitch perception in contexts. however, no neurophysiological study has been conducted. This study identified event-related potential (ERP) correlates of pitch judgments under different pitch contexts. Twenty-seven participants judged whether the tritone pair was perceived as ascending or descending after listening to a sequence of ascending or descending tone pairs. Cortical auditory evoked responses to the second tone of the tritone pair were compared across contexts. In the Rise context, standard stimuli evoked larger responses at Fp1; in the Fall context, deviant stimuli elicited stronger responses across all sites. These results suggest that frontal and central brain regions are involved in processing ambiguous pitch stimuli, and that ERP responses reflect the interaction between stimulus context and perceptual.