Children with Vision and Hearing Loss
By Stacy Shafer, Early Childhood Specialist & Kate Moss, Family Support Specialist, TSBVI, Outreach
What is Cerebral Palsy?
Cerebral Palsy or CP is a condition that is mainly characterized by an inability to fully control motor function. This may include muscle tightness or spasm, involuntary movement, and/or disturbance in gait and mobility.
It is NOT a disease, is not communicable, and is not progressive. It is caused by damage to the brain, rather than muscles. This damage can occur before, during or shortly after birth.
Lack of oxygen, illness, poisoning, and head injury are some factors that can cause cerebral palsy.
People who have CP may also experience a range of conditions in addition to impaired motor function. These may include:
- abnormal sensation and perception
- impairment of sight, hearing, or speech
- mental retardation
- difficulties in feeding, bladder and bowel control, and breathing (because of postural difficulties)
- skin disorders (because of pressure sores)
- learning difficulties
CP can range from very mild to very severe. No two people are affected in exactly the same way. Some children with mild CP may not be diagnosed until after they are two years old. There are three main types of CP:
- Spastic which produces stiff and difficult movement
- Athetoid which produces involuntary and uncontrolled movement
- Ataxic which produces a disturbed sense of balance, position in space and general uncoordinated movement
It is important to note that these three types of CP may also occur in various combinations. Physical therapists who work with children who have CP will often describe the child as having a low tone (hypotonia), high tone (hypertonia), or fluctuating tone.
Other terms you may hear them use in discussing CP refers to the area of the body affected by the brain damage. Problems to one side of the body are referred to as hemiplegia.
Quadriplegia occurs when the individual has upper and low body involvement. Diplegia describes lower body involvement and paraplegia describes upper body involvement. (Harris, 1987)
“Over 40-75% of children with cerebral palsy have some form of a visual problem or impairment.” (Black, P.D., 1980) They may have an acuity loss, field loss, oculomotor problem and/or a processing problem.
These conditions often result in visual concentration issues and/or problems with eye-hand coordination. It is very important that an eye care specialist be consulted regularly for possible treatment, including glasses, eye patching, surgery, etc.
An acuity loss typically makes things appear blurry. Nearsightedness (myopia) and farsightedness (hyperopia) are types of acuity loss caused when the image does not hit the retina correctly (refractive errors).
Glasses are prescribed to help improve refractive errors. Those of us who have an acuity loss and wear glasses know how much information we miss from our environment when we don’t have our glasses on.
Glasses are very important for a child who has CP and acuity loss. Glasses can greatly improve incidental learning or learning that takes place by observation.
The field of vision is everything you can see when you look straight ahead which is normally about 180 degrees in all directions. A field loss means that part(s) of the field is missing. Types of field losses include:
- hemianopsia: right or left, upper or lower half of the field is missing,
- central loss: like holding your fist up in front of your eyes,
- scotomas: isolated spots are missing from your vision,
- islands of vision: you can see only scattered spots, and
- peripheral loss: you can see straight ahead but misses information from the sides
An individual with CP may also experience conditions with their eye that can affect depth perception and smooth movements of the eye. These are called oculomotor problems and include:
- eye turns in towards the nose (esotropia or esophoria),
- eye turns out towards the ears (exotropia or exophoria),
- eye turns up (hypertropia or hyperphoria),
- eye turns down (hypotropia or hypophoria),
eye misalignment due to muscle imbalance (strabismus),
- lazy eye (amblyopia)
This means that the child has problems making sense of visual information. Cortical visual impairment or CVI causes processing problems. CVI can cause the vision to fluctuate from day to day and minute to minute. It can also impact depth perception and cause a field loss.
Visual concentration and eye-hand coordination
Children with CP may also have problems with visual concentration and/or eye-hand skills. Many of the children expend so much energy and concentration on keeping their body upright, controlling an accurate reach, etc. they have little left over to use for visual tasks.
Asking some children with CP to hold their body in alignment, look at a toy and then reach for it, might be like asking you to read *War and Peace* and put a bicycle together while serving your mother-in-law high tea.
We are asking the child to do too much at one time. If we can support and stabilize his body, he will be able to concentrate on looking and reaching. If trunk and head control is the skill you want to work on, you may not want to use a visual toy as a motivator.
As a team, you need to consider the types of demands you are placing on the child within any given activity.