The neocortex, including the auditory cortex, consists of highly diverse neuronal populations, with the anatomically prominent six-layered structure. Although different cortical layers and cell-classes encode auditory information differently, it still remains poorly understood how auditory coding across cortical layers is changed with age. In this proposal, we will test the hypothesis that auditory coding in the primary auditory cortex (A1) is changed with age in a cell-type-specific manner. We will specifically focus on one of major cortical cell groups, GABAergic inhibitory neurons, which are further classified into diverse subtypes. This is because the reduction of inhibitory neurotransmission has been observed throughout the ageing auditory pathway and has been implicated in the slowness of auditory processing in the ageing brain. Combining in vivo electrophysiological and optogenetic approaches in mice, this PhD project will concern how GABAergic contributions to auditory cortical computations are changed with age. This study will provide further insights into the mechanisms of the slowness in the ageing auditory system and the development of intervention strategies for the ageing auditory system.
in vivo electrophysiology
Advanced statistical analysis
SupervisorDr Shuzo Sakata
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