Hearing loss due to age, termed as presbycusis, falls into the sensorineural category. High frequency effect in this hearing loss type doesn’t let people understand that they have a problem.
Gradually, they have difficulty comprehending speech. In presbycusis, one hears speech but is unable to get what’s being said, ensuing in slurred speech. Later on, with increasing hearing loss, one can face speech and hearing problems simultaneously. Presbycusis is generally progressive, increasing with time.
Noise induced hearing loss (NIHL) or hearing loss from exposure to loud noise is quite common in our country causing damage in cochlea or inner ear. Noise pollution, unfortunately, is rampant and a big issue in India. Loud noise induced hearing loss can occur suddenly and be progressive in nature. However, hearing loss for two people can be entirely different although their exposure to noise level is the same. Then again, while one person can get affected, the other might not. Some people are highly prone to noise induced hearing loss.
In General, The Sources Of Noise Are –
1. Traffic 2. Firecrackers 3. Airports 4. Heavy and Small Industries
According to the 1998 report of National Institute for Occupational Safety and Health (NIOSH), sound more than 85 dB in 8 hours or over 91 dB in 2 hours on an average per day can be damaging for our ears.
These types of sounds hit the eardrums or inner ear causing conductive and sensorineural hearing loss, respectively.
Hearing loss can be genetic or hereditary. Genes are structural units of inheritance in living organisms – the carrier and bearer of heredity. Genes are generally of dominant or recessive types and can be responsible for hearing loss. It has been observed that in a familial history of gene induced hearing loss, many children are often born with hearing loss or develop it with age.
Various neurological disorders like multiple sclerosis or stroke can be responsible for hearing loss. These hearing loss types are mainly sensorineural. Many times, neurological disorders can damage myelin sheath of nerves. Once damaged, these cannot be fixed or created in a new way. This gives rise to sensorineural hearing loss. With time, this condition aggravates to profound hearing loss of about 110 dB – 120 dB with gradual wearing away of the auditory nerve.
External injuries like sudden blows to ears can damage eardrums, causing hearing loss. Head injury or skull fractures from road accidents can also initiate hearing loss.
Many people unknowingly poke or pour hot oil in ears due to ear pain. This can damage outer and middle ear creating hearing problems.
Physical trauma or injury can give rise to temporary or permanent hearing loss. Depending on the severity of trauma, severity of hearing loss can range from minimum to excessive.