S4-3. Population-level frequency tuning in human auditory cortex

Abstract

Sharp frequency tuning in the auditory pathway plays an important role in the perception of auditory signals. We herein tried to investigate the frequency tuning in the human auditory cortex of healthy controls and patients who were suffering from hearing disorders. We examined population-level frequency tuning in the human auditory cortex by recording auditory evoked magnetic fields elicited by pure tones embedded within band-eliminated broadband noises with different bandwidths by means of magnetoencephalography (MEG). The results obtained demonstrated that population-level frequency tuning in the human auditory cortex can be modulated by auditory focused attention, exposure to recreational sounds, and hearing impairments. The broadened population-level frequency tuning in an early stage may induce subconscious damages, which standard behavioral audiometric measures fail to detect. However, we suppose that these damages are cumulative and could lead to future irreversible hearing impairments such as chronic tinnitus and sensori-neural hearing loss.