Effect of sinusoidal versus rectangular amplitude modulated stimuli on the acoustic change complex

The acoustic change complex (ACC) is a cortical response evoked by a change to a steady, continuous auditory stimulus. The response has been linked to behavioral measures of sound discrimination and is observable in infants, children, and adults. The ACC is very sensitive to the acoustic properties of the stimulus, growing stronger when the change in the ongoing stimulus is more drastic. The ACC may be a reliable marker of binaural hearing ability, as it has been linked with behavioral measures of interaural phase or level difference tasks. The current study examines the impact of rectangular amplitude modulation versus sinusoidal amplitude modulation on the amplitude and latency of the ACC in normal hearing adult listeners. Additionally, this project aims not only to evaluate the enhancement of the ACC signal but also to investigate how that enhancement affects the relationship between the ACC and IPD performance. Preliminary results suggest that the amplitude of the ACC is more robust in response to rectangular amplitude-modulated stimuli compared to sinusoidal stimuli.