The human ear is a complex organ and hearing is a combination of several closely interconnected processes. Sound is made up of vibrations of air in the form of waves. The human ear picks up these vibrations and converts them into electrical signals which are then sent to the brain. The brain is where these signals are interpreted and translated into meaningful information. Examples of commonly used sounds are language and music.
Gradual hearing loss as age catches up (presbycusis) is a common condition. Over time noise contributes to the wear and tear of the ears, leading to hearing loss. Heredity and chronic exposure to loud noises also play an important role in hearing loss.
Some of the signs and symptoms of hearing loss that should alert you are -
Difficulty in understanding words, especially against background noise or in a crowd.
Muffed quality of speech and other sounds
Asking others to speak more slowly, clearly and loudly.
Withdrawal from conversations and social gatherings.
Hearing loss are of various types and the there exists a range of causes that could lead to hearing loss.
Hearing loss is essentially of two types -
Conductive hearing loss
Sensorineural hearing loss
Conductive hearing loss is generally caused by anything that interferes with the transmission of sound from the outer ear to the inner ear. Some of the potential causes could be as follows -
Middle ear infections (Otitis Media)
Damage to the eardrum by infection or injury
Rheumatoid arthritis that affects the joints between the ossicles, a rare condition
Blockage of the outer ear (by wax)
Collection of fluid in the middle ear, also known as "glue ear" (in children).
Otosclerosis, a condition in which the ossicles of the middle ear become immobile because of growth of the surrounding bone.
Sensorineural hearing loss occurs due to the damage to the pathway for sound impulses from the hair cells of the inner ear to the auditory nerve and the brain. Some of the possible causes are -
Brain tumor
Stroke
Acoustic trauma to the hair cells, such as an injury caused by loud noise.
Viral infections of the inner ear
Use of certain drugs such as aspirin, quinine and some antibiotics, which can affect the hair cells.
Multiple sclerosis
Infections or inflammation of the brain or outer layers of the brain as in case of meningitis.
