Temporal integration reflected by frequency following response in auditory brainstem
Xua,b , Qin
Temporal integration reflected by frequency following response in auditory brainstem
Auditory temporal integration (ATI) has been widely described in psychoacoustic studies, especially for loudness
perception. Loudness increases with increasing sound duration for durations up to a time constant about 100 ~ 200 ms, and
then loudness becomes saturated with more duration increase. However, the electrophysiological mechanism underlying the
ATI phenomenon has not been well understood. To investigate ATI at the brainstem level of auditory system and its
relationship to cortical and behavioral ATI, frequency follow response (FFR) was acquired in our study. Simultaneously, ATI
in auditory cortex was evaluated by cortical response P1. Behavioral loudness and electrophysiological measures were
estimated from normal-hearing young adults for vowel /a/ whose durations varied from 50 ms to 175 ms. Significant effects
of stimulus duration were found both on FFR and P1 amplitudes. Linear regression analysis revealed that as stimulus
duration increased, brainstem FFR amplitude was significantly associated with cortical P1 amplitude and behavioral loudness,
which confirmed the existence of temporal integration in auditory brainstem. Moreover, behavioral loudness ATI was better
predicted using brainstem and cortical measures together than merely using each one separately, indicating an interplay and
coordination for ATI across the three levels along auditory pathway.
Auditory temporal integration (ATI), frequency following response (FFR), cortical response P1, loudness
Temporal integration reflected by frequency following response in auditory brainstem
Auditory temporal integration (ATI) has been widely described in psychoacoustic studies, especially for loudness
perception. Loudness increases with increasing sound duration for durations up to a time constant about 100 ~ 200 ms, and
then loudness becomes saturated with more duration increase. However, the electrophysiological mechanism underlying the
ATI phenomenon has not been well understood. To investigate ATI at the brainstem level of auditory system and its
relationship to cortical and behavioral ATI, frequency follow response (FFR) was acquired in our study. Simultaneously, ATI
in auditory cortex was evaluated by cortical response P1. Behavioral loudness and electrophysiological measures were
estimated from normal-hearing young adults for vowel /a/ whose durations varied from 50 ms to 175 ms. Significant effects
of stimulus duration were found both on FFR and P1 amplitudes. Linear regression analysis revealed that as stimulus
duration increased, brainstem FFR amplitude was significantly associated with cortical P1 amplitude and behavioral loudness,
which confirmed the existence of temporal integration in auditory brainstem. Moreover, behavioral loudness ATI was better
predicted using brainstem and cortical measures together than merely using each one separately, indicating an interplay and
coordination for ATI across the three levels along auditory pathway.
Auditory temporal integration (ATI), frequency following response (FFR), cortical response P1, loudness