人工耳蜗

A cochlear implant system has two main parts. The external component includes a microphone, a speech processor, and a transmitter. The microphone picks up sounds from the environment, and the speech processor digitizes and codes them into electrical signals. The transmitter sends these signals wirelessly through the skin to the internal component. The internal component, which is surgically implanted, consists of a receiver and an electrode array. The receiver picks up the signals from the external transmitter and converts them into electrical impulses. These impulses are sent to the electrode array, a thin wire that is carefully threaded into the cochlea, the spiral-shaped part of the inner ear. Different electrodes along the array stimulate different parts of the auditory nerve. The nerve fibers at the base of the cochlea normally transmit high-frequency sound information, while those at the apex transmit low-frequency information. The implant’s speech processor is programmed to send high-frequency signals to the electrodes at the base and low-frequency signals to those at the apex, mimicking the natural tonotopic organization of the cochlea. The brain learns to interpret these patterns of electrical stimulation as meaningful sound, including speech.