Disorders of senses
Deaf and Hard-of-Hearing
Hearing loss is a generic term that applies to people who are hard-of-hearing of deaf.
Hard-of-hearing is a condition that makes understanding speech difficult through use of the ears alone, with or without a hearing aid.
Deaf is a condition in which a person is unable to understand speech through use of the ears alone, with or without hearing aid.
There are three major types of hearing loss: conductive, sensorineural, and mixed.
Conductive loss:
Conductive loss of hearing is a condition in which sound does not pass through the external and middle ear to reach the inner ear, resulting in the condition hard-of-hearing. Conductive loss of hearing is caused:
In the external ear by buildup of impacted wax, injury, or infection
In the middle ear by otitis media produced by colds, sinus infections, allergies, or small or blocked Eustachian tubes.
Otosclerosis, progressive deafness of unknown etiology, is caused by formation of spongy bone, especially around the oval window, resulting in stiffening of stapes, preventing proper vibration.
Sensorineural loss:
The inner ear hearing apparatus of the cochlea is affected. This is the site at which sensory receptors convert sound waves into neural impulses that are transmitted to the brain for translation. In sensorineural hearing loss, balance is sometimes affected because the vestibular apparatus is also located in the inner ear. This is the most frequent type of loss in people who are born deaf. Causes are a result of the following:
- idiopathic (unknown)
- hereditary factors
- meningitis
- mumps
- scarlet fever
- encephalitis
- measles
Mixed type of hearing loss is a combination of the two conditions already identified and is common in senior citizens.
Physical activity
People with hearing loss generally can participate in all types of physical activity. Prescription procedures are the same as for other people.
Regular exercise by people with hearing loss produces the same positive physiological, psychological and skill benefits as for individuals with no hearing loss. There are some more benefits:
- more opportunities to improve socialization skills in group activities
- practice and improvement in balance
- learning to work with and relate to a new leader in a group
- improved self – image, confidence
- spatial orientation
Visual Impairment
Is a generic term that includes a range of visual acuity from legal blindness with partial sight to total blindness. Legal blindness is vision of 20/200 or less with the best correction. It is the ability to see at 20 feet what the normal eye sees at 200 feet, blind by acuity. Blind by visual field means having a visual field of less than 10 degree of central vision, or having tunnel visional perception or the inability to recognize a strong light shown directly into the eye, sometimes called “no light perception”. In approximately 95% of the people who are considered blind there is some residual vision that needs to be used to allow the person to participate as normally as possible.
In younger populations, causes are attributed to birth defects, including congenital cataracts and optic nerve disease. Another now uncommon cause in children is retinopathy of prematurity. Tumors, injuries, and infectious diseases are possible but less common causes. In persons who are elderly, diabetes, macular degeneration, glaucoma, and cataracts are leading causes. Visual impairment may occur concomitantly in people with cerebral palsy and mental retardation.
Physical activity
Persons with visual impairment usually have poor balance, forward head, low cardiovascular fitness, obesity, lack of confidence, timidity, self-stimulatory behaviors, and few social skills.
People with a visual impairment can participate in many vigorous physical activities with some adaptations. In fact, regular exercise by people with visual impairment produces the same positive physiological and skills benefits as for individuals without a disability. It includes:
- More opportunity to improve socialization skills
- Practice and improvement in balance skills
- Improvement in self-image, confidence, and spatial orientation
- Improvement in cardiovascular fitness
- Decrease in obesity