摘要 |
<p>"Hearing" without involving the ear is realized by electrical conduction of the sound-representing signals on a carrier optimally in the frequency range of 15-60 kHz, from an electrode held against a person's head to the auditory cortex and possibly to the auditory nerve. This is called a "cortical hearing aid". The ability of the person to recognize sounds with a cortical hearing aid is enhanced by introduction of significant distortion of the audio signals, especially low-order harmonics of the audio frequencies. The distortion acts as a substitute for distortion ordinarily occurring in the ear but disregarded in the hearing process.</p> |