About Hearing Loss
“Hearing loss can occur at any age for a variety of reasons. Babies can be born with hearing loss due to complications of prematurity, family genetics, or a syndrome, to name a few. Addressing it early supports language and literacy development. An adult acquires a hearing loss for many reasons such as the natural aging process, noise exposure, or head trauma. Untreated hearing loss can lead to social isolation and cognitive decline. Some hearing losses occur due to middle or inner ear infections and can be treated with medication or surgery, in some cases. Most cases of permanent hearing loss are managed through the use of personal hearing aids, cochlear implants, and/or assistive listening devices. Hearing loss can be gradual or sudden and often the true cause is unknown. For these reasons, it is important that individuals have their hearing assessed by an Audiologist as part of a routine health check-up.”
– Canadian Academy of Audiology
People with hearing loss are more likely to experience social isolation and depression as their hearing deteriorates. Not being able to understand speech leads to frustration which can turn into embarrassment, withdrawal from social situations and loneliness. These psychological effects can be easily avoided through correct assessment and diagnosis of the hearing problem by an Audiologist in conjunction with appropriate treatment options such as communication strategies, assistive listening devices, hearing aids, FM systems, etc.
How do we hear?
Sound waves enter the outer ear canal and gets transmitted through the ear canal to the middle ear where there are three tiny bones or ossicles which then transmits the sound vibrations to the inner ear. The cochlea lies within the inner ear and is a snail shaped organ that is filled with fluid and contains thousands of tiny hair cells. The vibrations travel through the cochlea causing the fluid to bend the hair cells. As the hair cells bend, the nerve impulses are passed through the auditory nerve to the brain where they are interpreted and analyzed as sound.
Types of Hearing Loss
There are three main categories of hearing loss
1) Sensorineural
2) Conductive
3) Mixed
Sensorineural hearing loss is a permanent hearing loss that occurs
due to damage in either theinner ear also known as the cochlea or
along the auditory nerve when electrical impulses get disrupted along
the pathway up to the brain.
Causes of sensorineural hearing loss include noise exposure, certain
drug treatments, head trauma, genetics and aging to name a few.
Sensorineural hearing loss can present itself differently in different
people depending on where the damage is located: sometimes just
volume is affected, other times both clarity and volume can be
affected. Individuals may report that sounds are quiet, distorted or
muffled.
Sensorineural hearing loss as a result of aging is called presbycusis
and is quite common as it can begin to occur in individuals as young
as fifty years old. Typically, high frequencies are affected first
resulting in decreased clarity, difficulty hearing in noise as well as
mishearing of words. High frequency hearing loss is also common in
individuals exposed to significant noise levels over long periods of
time.
Conductive hearing loss is a result of the inability of sound to reach
the organ of hearing or cochlea. The cochlea is functioning optimally
however blockage in the outer ear attenuates the sound resulting in a
hearing loss. Conductive hearing losses are typically known to be
non-permanent in nature as they usually can be corrected using
interventions such as surgery or medications. Causes of conductive
hearing loss include significant wax buildup, fluid buildup in the
middle ear, anatomical abnormalities of the ear canal, pinnae or
middle ear bones.
A mixed hearing loss occurs when both sensorineural hearing loss as
well as conductive hearing loss are present.