What's the difference between cochlear implant and hearing aid?

Hearing AIDS are different from cochlear implants. Hearing AIDS only play a role in amplifying sound. However, the principle of this sound amplification is different from the unified amplification of microphone sound, but the part with hearing loss is selected for amplification. The premise of using hearing AIDS is that patients still have residual hearing, that is, the residual hearing of patients is generally below 85 decibels, so that patients still have effects after using hearing AIDS. Of course, some patients have residual hearing above 85 decibels, and they can hear with hearing AIDS. However, the articulation of this sound is very poor. They often communicate with people face to face, only hearing voices, but they don't know what others are saying.

Cochlear implants are generally suitable for people with no residual hearing, or residual hearing above 85 decibels, and the effect of using hearing AIDS is very poor. People have an auditory sensory organ called cochlea, in which there are auditory sensory nerves. When the auditory receptor is damaged, the external sound and energy cannot be converted into nerve impulses of the auditory system, and people can't hear the sound. The function of cochlear implant is to directly stimulate the auditory nerve with current to generate pulses, but this pulse must have the same function as cochlea and the ability to program sounds, which is called coding function. Then, the auditory organs arrange sounds into neural codes, which are decoded by the cerebral cortex and become language signals that can be accepted and recognized by the human brain.

Now with the development of cochlear implant technology, the problem of hearing impairment has been greatly solved. Because each patient's ability to distinguish sounds is different, the effect after cochlear implantation is also different, and the best effect can be to understand more than 90% of words. Clinically, some people can continue to work as engineers and lawyers after installing cochlear implants.