AUTHOR=Liu Xiuping , Zhang Oliver , Chen Amber , Hu Kaili , Ehret Günter , Yan Jun TITLE=Corticofugal Augmentation of the Auditory Brainstem Response With Respect to Cortical Preference JOURNAL=Frontiers in Systems Neuroscience VOLUME=13 YEAR=2019 URL=https://www.frontiersin.org/journals/systems-neuroscience/articles/10.3389/fnsys.2019.00039 DOI=10.3389/fnsys.2019.00039 ISSN=1662-5137 ABSTRACT=

Physiological studies documented highly specific corticofugal modulations making subcortical centers focus processing on sounds that the auditory cortex (AC) has experienced to be important. Here, we show the effects of focal conditioning (FC) of the primary auditory cortex (FCAI) on auditory brainstem response (ABR) amplitudes and latencies in house mice. FCAI significantly increased ABR peak amplitudes (peaks I–V), decreased thresholds, and shortened peak latencies in responses to the frequency tuned by conditioned cortical neurons. The amounts of peak amplitude increases and latency decreases were specific for each processing level up to the auditory midbrain. The data provide new insights into possible corticofugal modulation of inner hair cell synapses and new corticofugal effects as neuronal enhancement of processing in the superior olivary complex (SOC) and lateral lemniscus (LL). Thus, our comprehensive ABR approach confirms the role of the AC as instructor of lower auditory levels and extends this role specifically to the cochlea, SOC, and LL. The whole pathway from the cochlea to the inferior colliculus appears, in a common mode, instructed in a very similar way.