hearing-impairment, also called auditory impairment is a condition of partial or complete loss of sounds. It is a condition which prevents a person from perceiving sounds and understanding speech. ghspeaks
CLASSIFICATION OF HEARING IMPAIRMENT BASED ON
- AGE OF ONSET
These are congenital hearing loss and Adventitious or acquired hearing loss.
- Congenital Loss:- This is the learning loss that is present at birth.
- Adventitious/Acquired Loss:- This hearing loss occurs after birth. There are two types namely Pre-linguistic and Post lingual.
. Pre-linguistic loss is when the loss takes place before speech is acquired. ii. Postlingual loss occurs after the acquisition of speech.
(B) DEGREE OF LOSS
This deals with the intensity of the hearing loss. Two types are identified here.
- MILD-MODERATE:- Losses ranging between 26 and 65dB are mild-moderate. Individuals with mild-moderate losses can benefit from the use of hearing aids. They are also known as hard of hearing.
- SEVERE TO PROFOUND:- these group of people are also referred to as deaf. They are unable to hear but communicate using sign language, gestures etc. Their losses threshold range between 66dB and 125dB. Sounds is measured in units. It is usually done in decibels (dB) and frequency. The lower the dB the smaller the sound and the larger the dB, the louder the sound. hearing-impairment
(B)TYPE OF LOSS
The types of hearing loss are categorized into four.
- CONDUCTIVE HEARING LOSS
This could be caused by a blockage or complications in the outer or middle ear as a result of too much wax in the auditory channel. In children, the presence of foreign materials like clay, eraser can cause this hearing loss.
- Sensory – nueral hearing impairment.
This is where the inner ear such as the chochlea and auditory nerves is damage. Auditory nerves are connected to the sense of hearing and any damage to it as a result accidents, disease may result in hearing impairment.
- CENTRAL HEARING LOSS:- This occurs when the nervous system involving the brain which interpretes sound waves for understanding is damaged. All senses have their individual centres in the brain. Eg. Smell, taste, visual, auditory etc. Therefore, if the auditory cortex is damaged, one cannot hear well or at all.
- MIXED HEARING IMPAIRMENT
This results when there is a combination of any two or all of the conductive, sensory neural and central hearing loss eg. Hearing, loss due to blockage in the lower or middle ear, damage to the auditory nerves as well as damage to the auditory cortex in the brain.
SIGNS / CHARACTERISTICS / INDENTIFICATION OF HEARING IMPAIRED CHILFEN
(A) CONDITIONS OF THE EAR(S)
- There is frequent discharge of pus from any of the ears or from both.
- Often complains of earache or headache
(|B) BEHAVIOUR OF THE AFFECTED INDIVIDUAL
- Watches the lips and the face of a speaker for cues in order to understand.
- Poor response to call from behind him.
- The child frequently asks for repetition of everything said to him.
- Frequently turns the better ear towards the source of sound when listening.
- The child normally shouts inappropriately when speaking to others.
- A child who is poor at dictation but which is not a true reflection of his academic performance.
- Children with behavioural problems such as inattentiveness and restlessness in class
A child who gives verbal false responses.
CAUSES OF HEARING IMPAIRMENT
There are hereditary or genetic and environmental causes of hearing impairment.
- HEREDITARY / GENETIC CAUSES
- THE RHESUS FACTOR
When an Rh negative blood mother conceives a fetus who inherits Rh positive blood from its father, the two cannot live in harmony. This is because the Rh positive fetus produces some antigens from its red blood corpuscles through the unbilical cord and the placenta into the mother’s blood stream by producing some antibodies from her plasma into the festus blood steam. When this happens, the festus’ antigens and the mother’s antibodies attach to each other this destroying the baby’s red blood corpuscles resulting in reduced oxygen supply anoxia and eventually hearing loss.
- DEOXYRIBONUCLEIC ACID
When a fetus inherits and inactive genes which, for instance, are responsible for the formation of any vital part of the hearing organ, a hearing loss may occur.
(B) ENVIRONMENTAL CAUSES
- Maternal malnutrition.
- Drug abuse
- Maternal disease eg.Rubella
- Placenta hemorrhage eg. When a large amount of blood flows from a damaged blood vessel connected to the hearing organ.
- Prolonged labour
- Wrong use of forceps during the birth process 8.Weak nerves of the hearing organ resulting from old age.
MANAGEMENT OF HEARING IMPAIRED CHIDLREN
- Speak at normal speed without exaggerating lip movements. Thus speak clearly and at moderates pace.
- Let the children see your face when talking
- Avoid speaking while writing on the board.
- Repeat questions and answers given by other student
- Reduce the general level of noise in the room.
- Gain pupils attention before speaking
- Write key ideas of the lesson on the chalkboard.
- Do not put your hard or object in your mouth when speaking
- Explain the problem to other pupils so that they can turn towards the pupils when speaking or reading.
10.Use gestures or sign language to help with communication.
11.Use a lot of Visual displays eg. Diagrams, pictures, graphs. You can equally use overhead projector to note important points.
12.Avoid frequent movement around the classroom. COMMUNICATION DISORDERS
Communication is usually understood to mean exchange of information and ideas. An idea or information can be expressed through speech, writing, body movements or signals. In most communications, two people are involved.
The sender and the receiver. The sender is the one who expresses the idea (message) and the receiver is the person who responds to the message.
Communication can be both verbal and non-verbal. Verbal Communication uses speech and talking whilst non-verbal communication uses gestures and facial expressions. According to Kirk, Gallagher and Anastasiaw (2002) speech is the systematic oral production of words of a given language. Lahey (1988) defines language as a code whereby ideas about the world are expressed through conventional systems.
Communication disorders, therefore, is the inability of an individual to express his ideas or thought meaningfully to another through oral or non-verbal forms. This means that if you speak and your listeners do not normally understand, then there is communication disorder.