Hearing Impairment Symptoms and Causes
It is inability to hear well or not hearing at al
A person who is not able to hear as well as someone with normal hearing – hearing thresholds of 20 dB or better in both ears – is said to have hearing loss. Hearing loss may be mild, moderate, severe, or profound
Types of Hearing Loss
A hearing loss can happen when any part of the ear or auditory (hearing) system is not working in the usual way.
The outer ear is made up of:
the part we see on the sides of our heads, known as pinna
the ear canal
the eardrum, sometimes called the tympanic membrane, which separates the outer and middle ear
The middle ear is made up of:
three small bones called ossicles that send the movement of the eardrum to the inner ear
The inner ear is made up of:
the snail shaped organ for hearing known as the cochlea
the semicircular canals that help with balance
the nerves that go to the brain
Auditory (ear) Nerve
This nerve sends sound information from the ear to the brain.
Auditory (Hearing) System
The auditory pathway processes sound information as it travels from the ear to the brain so that our brain pathways are part of our hearing.
There are four types of hearing loss
1. Conductive Hearing Loss
Hearing loss caused by something that stops sounds from getting through the outer or middle ear. This type of hearing loss can often be treated with medicine or surgery.
2. Sensorineural Hearing Loss
Hearing loss that occurs when there is a problem in the way the inner ear or hearing nerve works.
3. Mixed Hearing Loss
Hearing loss that includes both a conductive and a sensorineural hearing loss.
4. Auditory Neuropathy Spectrum Disorder
Hearing loss that occurs when sound enters the ear normally, but because of damage to the inner ear or the hearing nerve, sound isn’t organized in a way that the brain can understand
Types of hearing impairment
a) Hearing impairment – it is inability to hear well or not hearing at all. It can be classified according to ;
Age of onset
Part of the ear affected
A: Classification according to severity
There are five categories of hearing impairment according to severity loss
1- Learners with slight hearing loss-
a) these learners can follow normal conversation if there is no noise but need face the speaker
b) They may have difficult hearing a distant speech
c) They will not have difficult in school situation
2 – Learners with mild hearing loss
They may only understand a conversation at a distance of 1m. Such learners will only follow a conversation if the room is quite and when they face the speaker
3 – Learners with moderate hearing loss
The learners may have difficult hearing in all situations and can only follow a loud conversation
They may defective speech
They have limited vocabularies and require the help of hearing aid or speech training 4-Learners with severe hearing loss
They only hear loud voices
They are able to identify environmental sound and discriminate vowels but not consonants
They require hearing aids and instruction to be in total communication
5 – Learners with profound hearing loss
They may loud sounds that have vibrations
They depend on vision rather than hearing an avenue of communication
They use sign languages
B: Classification according to age of onset
There are two categories;
1-Pre-lingual deafness: is someone who was born with a hearing loss, or whose hearing loss occurred before they began to speak. Infants usually start saying their first words around one year.
2-Post-lingual deafness: is a deafness which develops after the acquisition of speech and language, usually after the age of six.
C: Classification according to part of the ear affected
The ear is functionally divided into three parts i.e. outer, middle and the inner ear. Any infection or damage to any part causes hearing loss. There are three types of hearing loss according to type of the ear affected.
Conductive Hearing Loss
This occurs when there is a condition of the outer or middle ear that prevents sound from reaching the inner ear. Causes can include blockage of the outer ear or ear canal, an ear infection with fluid, or a malformation of the outer or middle ear.
In some cases, conductive hearing loss may be temporary or treatable with medication or surgery.
Sensorineural Hearing Loss
This is usually a result of a problem in inner ear or with the cochlea, either through malformation or damage. Damage can occur from infections such as meningitis, or as a side effect of certain medications.
Mixed Hearing Loss
This is a combination of conductive and sensorineural hearing loss. The causes and options are the same as those described above.
Types of hearing difficulty
1- Hard of hearing
They are learners with despite loss of hearing, they have enough hearing rates called residual hearing. They can hear speech and acquire spoken language without use of hearing aid.
However for them to hear;
One should be loud
Place the individual near the speaker
Provide a quite environment
Face the speaker
Use a suitable teaching aid
Characteristics of learners of hard of hearing
Ask for repletion of what has been said Have difficult in group discussion Misunderstand others Unable to monitor their voices Have difficulty understanding directions They curve their ears in the direction of the sound Stare at the speaker
2 – Deaf
These are individuals whose hearing is severe, cannot hear or understand even when the speaker is made louder.
Characteristics of learners with hearing impairment
Difficulty following verbal directions
Difficulty with oral expression
Some difficulties with social/emotional or interpersonal skills
Will often have a degree of language delay
Often follows and rarely leads
Will usually exhibit some form of articulation difficulty
Can become easily frustrated if their needs are not met which will lead to some behavioral difficulties
Slow and labored speech
Mainly use signs or gestures to be understood
Ask for repletion of what they have not hard
They tend to misunderstand others
Unable to monitor their voices and hence speak loudly or softly
Avoid participating in activities
They curve their ears in direction of the sound
They stare at the speaker
They appear confused
They may withdraw from the rest
Inability to hear in a loud environment
Poor verbal communication between the teacher and the learner
Inability to follow school routine
Difficulty with several speech sounds and experience articulation difficulties.
Background noise will interfere with speech reception.
Early reading skills such as letter/sound identification can be affected.
Speech and oral language will not develop spontaneously if the hearing loss is prelingual (before language).
Advice on a suitable school placement
Advice parents to seek medical care
Use peers give the affected learners a preferential sitting
Counseling services to deal with stigma, self acceptance etc
Encourage the learners to observe general basics of hygiene
Refer the affected learner for medical treatment
Show positive attitude
Adapting the curriculum
Use residue learning (small amount of learning)
Have personal contact with the learner provide eye glass for the low vision learner
Teach survival skills e.g visual skills, social skills, motor skills etc.