THE CONCEPT OF HEARING AND HEARING IMPAIRMENT
By J. A. Ansah
MEANING OF HEARING
Hearing is one of the five traditional human senses and refers to the ability to perceive sound through the ears. It involves the detection of vibrations (sound waves) in the environment and their interpretation by the auditory system in the brain.
Scientific Definition: Hearing is the process by which the ear detects sound waves and converts them into electrical signals that are sent to the brain, where they are recognised as sound.
HOW HEARING WORKS (SIMPLE STEPS)
1. Sound waves enter the outer ear.
2. They travel down the ear canal and vibrate the eardrum.
3. These vibrations move the ossicles (tiny bones in the middle ear).
4. The movement is transferred to the cochlea in the inner ear, filled with fluid and sensory hair cells.
5. Hair cells generate nerve signals, sent via the auditory nerve to the brain.
6. The brain interprets these signals as sounds (e.g., speech, music, danger).
EXAMPLES
1. You hear a doorbell ring, and your brain processes it as a sound signal.
2. A teacher speaking in class is heard and understood through auditory processing.
HEARING IMPAIRMENT (HEARING LOSS)
A person with hearing impairment may not be able to detect or process these sounds fully. Hearing impairment is a broad term encompassing partial or total inability to hear. It can affect one or both ears and varies in severity. It can be congenital or acquired and ranges in severity from mild to profound. According to the World Health Organisation (WHO), over 430 million people worldwide live with disabling hearing loss, significantly affecting communication, education and social integration.
Hearing loss makes it difficult or impossible to hear speech and other sounds. There are different types of hearing loss, and they can range from mild, moderate, severe, or profound. Some types of hearing loss are temporary, and some are permanent.
The Ear
Source: https://my.clevelandclinic.org
TYPES OF HEARING IMPAIRMENT (HEARING LOSS) AND SOLUTIONS
There are three types of hearing loss. Each one may be caused by a number of factors that affect a particular part of your ear. Here is an overview of each for a basic understanding. Proper diagnosis requires you to consult a hearing impairment specialist or an audiologist.
1. Conductive Hearing Loss: This hearing impairment is caused by problems with your ear canal, eardrum or the middle ear. This is also caused by a problem with your outer or middle ear, so sound cannot pass through to your inner ear.
Conductive hearing loss is more common in children. It can sometimes be treated.
Causes:
- Outer ear, ear canal or middle ear malformation
- Fluid in the middle ear
- Ear infection
- Allergies
- Poor function of the Eustachian tube
- Otosclerosis: An inherited disorder that causes hearing loss due to the ear’s inability to amplify sound
- Perforated or torn eardrum
- Benign tumours: They are abnormal but non-cancerous collection of cells which do not spread to or invade other parts of the body.
- Earwax
- Ear canal infection
- Presence of a foreign body
- Abnormal bone growth in your middle ear (known as otosclerosis)
2. Sensorineural Hearing Loss: Also known as nerve-related hearing loss, this condition is brought about by issues with your inner ear. This occurs when there is a problem with your cochlea, which is the hearing organ in your inner ear or your auditory (hearing) nerve. It may be caused by:
Sensorineural hearing loss is often permanent.
Causes:
- Exposure to loud noise (known as noise-induced hearing loss)
- Head trauma or head injury
- Virus or disease
- Autoimmune inner ear disease
- Family history of hearing loss
- Aging (presbycusis)
- Inner ear malformation
- Meniere’s Disease: An inner ear disorder that causes episodes of vertigo (spinning)
- Otosclerosis tumours
- Infections
- Some medicines and chemicals
3. Mixed Hearing Loss: This is a combination of the two hearing impairments mentioned above. It could be caused by damage in the outer or middle ear and in the inner ear or auditory nerve.
4. Auditory Processing Disorders: These occur when your brain has trouble processing sound. This makes it hard to understand speech or to know where sounds are coming from.
WHAT ARE THE SYMPTOMS OF HEARING LOSS?
The first signs of hearing loss can be hard to notice because they usually come on gradually. They might include:
• having trouble hearing in noisy places
• having trouble hearing people on the phone or if they are not facing you
• often asking people to repeat themselves
• hearing sounds as muffled, as though people are mumbling
• the need to have the TV up louder than what other people want
• often missing your phone or the doorbell ringing
• hearing buzzing or ringing in your ears
• avoiding situations because you have trouble hearing
Your child might have hearing loss if:
• they do not startle at a loud noise or turn their head towards a sound
• they start speaking later than other children their age
• their speech is unclear, compared with other children their age
• they want the TV volume up high
• they do not understand and follow instructions as well as other children their age
• they need people to repeat themselves
• they are struggling at school
Inclusion is not bringing people into what already exists. It is creating a new space, a better space for all.
Source: Ansah, J. A. (n.d). Training manual for undergraduate special education students. Unpublished.
