Uncomfortable loudness level on auditory-evoked responses and spontaneous activity in the auditory pathway

摘要

The UCL (uncomfortable loudness level) is an important factor in hearing aid fitting and the sound design of a notification sound signal. The UCL can be measured by asking for a subjective judgment. As this method requires a great deal of time with loud sounds, a heavy load is applied on participants. An objective UCL estimation method without the load on participants is required. In this study, to construct a neurophysiological index of the UCL, auditory evoked potentials and auditory evoked neuromagnetic response fields (which reflect auditory information processing), and the level dependency characteristics of the brain's spontaneous magnetic field's alpha wave (which reflects the comfort of the auditory stimuli) were conducted. The activity of the auditory pathway and UCL-sensitive reactions were observed.