It is important to understand that cochlear implants stimulate a 'functional' auditory nerve, not a damaged one. Cochlear implants bypass the cochlea where hair cells that determine sounds have been damaged. The electrodes are able to stimulate that nerve that sends sound signals to the brain for interpretation. For generations, the belief was that when hearing loss occurred, the auditory nerve was 'dead' or damaged. When researchers figured out that was not the case, it led to the possibility of and development of cochlea implants.

The auditory nerve can be damaged. In that event a CI will not work. Prior to receiving a CI, it is typical to have an MRI and brain scan to determine whether or not there is something that would make a CI ineffective. Acoustic neuroma tumors can be the cause. In most cases they affect one ear, not both. That causes single sided deafness. There are remedies for SSD that involve implanted devices. That is a whole different topic.

Most medical professionals who are practicing today do not use the term 'nerve deafness'. They understand that assumption is no longer true. However, because many people were told, years ago, that they had nerve deafness, this is still a common statement.

If anyone is considering a cochlear implant, it would be wise to be tested and examined in the audiology department of a university that is doing research in this area. There are many of them.