Article from “2013 Consumer’s Guide to Hearing Aids,” James Wilson Group Solutions, L.P. USA. www.theconsumersguides.com
Hearing problems are grouped according to the location of the damage or defect.

http://www.pnas.org/content/97/13/6939/F1.expansion.html.
Sensorineural
Also know as nerve-type hearing loss, this type of gradually-diminished hearing is commonly associated with the aging process. Due to hair cell (stereocilia) damage within the cochlea, the auditory nerve cannot deliver signals to the brain correctly. This causes sounds to be distorted and certain consonants to be missed.
Patients may complain that people seem to mumble or that they hear but do not understand. Approximately 80 percent of adult patients with complaints of hearing problems suffer from this type of loss. Sensorineural losses may be helped with proper assessment and fitting of hearing aids.

Conductive
This type of hearing loss occurs when sound is inadequately conducted through the external or middle ear to the inner ear. The overall intensity (loudness) of sound is diminished, but sound clarity is usually intact if sufficient volume is present.
Approximately 20 percent of patients with complaints of hearing problems suffer from this type of loss. Conductive losses may be helped with hearing aids or medical or surgical intervention. Conductive hearing loss may occur along with sensorineural loss or alone.