Deafness is a medical condition or state where a person is unable to hear, or in simple words, it is a loss of hearing. Hearing evaluation is a crucial step in determining the extent and nature of this condition. There can be many reasons behind deafness like illnesses or physical trauma. Genetic factors can also be accountable for loss of hearing. Another common reason of deafness is an excessive exposure to noise. Deafness is categorized into different types depending on the symptoms. Following are given few types of deafness.
Conductive: Conducting hearing loss is a type of deafness in which sound is unable to conduct through the outer or middle ear. It is the mild form of hearing loss and in majority of the cases the sound quality remains unaffected if amplified.
Perceptive: Perceptive hearing loss is a type of deafness in which sound waves may reach the inner ear but the person unable to sense the sound because of injured nerves that lead to the brain. The sensorineural hearing loss is a hearing loss in which the inner ear, the cochlea or the auditory nervous system is dysfunctional. It is quite unusual to have a hearing loss because of impaired auditory sensors of brain.
Deafness due to Genetic Factors: If there are signs of prevailing deafness gene in the family, one can expect to see the cases of deafness in the coming generations as well. However, some kind of congenital impairment can also cause hearing loss.
Deafness caused due to Exposure to Noise: It is also a common type of deafness. Those who have a long term exposure to noise often experience deafness or hearing loss. There can be different factors causing deafness due to noise such as car stereos, noises produced by vehicles on the roads, air traffic, or noise produced by industrial facilities. Another common reason behind this type of deafness is the increased usage of headphones by the people.
Deafness caused due to Diseases: There are many diseases which can cause deafness in a person such as meningitis, measles, mumps and otosclerosis. There are certain other medical factors that can cause impairment in the auditory system such as premature births and AIDS.
Pre-lingual Deafness: Certain congenital factors are accountable for pre-lingual deafness. It can also develop before a person begins to acquire language and speech.
Post-lingual Deafness: Post-lingual deafness is opposite to the pre-lingual deafness. When a person suffers from deafness somewhere after the acquisition of speech and language, it is called post-lingual deafness.
Unilateral Hearing Loss: Unilateral hearing loss is a kind of deafness where a person can hear normally from one ear and having difficulty hearing from other.
Deafness due to Ear Injury: If a person’s eardrum gets damage, he/she will have difficulty in hearing. Eardrum is a thin membrane between ear canal and the middle ear.
He who doesn’t differentiate between the amplitudes and frequencies of sound waves is one suffering from any of the kinds of deafness.