Muscle Tone and Development When a Child has a Visual Impairment
By Kateri Gullifor
When working with an infant with a visual impairment, it is crucial to consider intervention strategies in order to promote muscle tone development. Many children with visual impairments have low muscle tone in their trunk or abdominal area (Ferrell, 2011). Experience with movement is key to the development of muscle tone in young children (Wiener, Welsh, Blasch, 2010). Children with visual impairments often lack the motivation or incentive in their environment to reach, grasp, move and explore. It is important for an EIVI professional to provide information to families and other early intervention specialists regarding the importance of encouraging and promoting exploration and movement.
Hypotonia affects the posture, balance, coordination, and locomotion of children who are visually impaired (Chen, 2014). This low muscle tone seems to be related to the absence of sufficient vision to motivate head movements that contribute to the development of the ability to shift weight and the development of the muscles in the trunk and arms (Chen, 2014). If this motivation to move and explore is not remediated by alternate stimuli, hypotonia will have long term effects on the child. Low tone contributes to difficulty maintaining an erect posture, causes “loose” movement patterns (because the hips and shoulders are overly mobile) and can cause clumsiness and slouching through the upper back (Pogrund, Fazzi, Lampert, 2002).
Two possible reasons for low muscle tone (hypotonia) in some babies with visual impairments are: (a) they have not had enough experiences pushing up on their hands and arms while lying on their stomachs, or (b) not enough experience twisting and turning the body when in a seated position (Ferrell, 2011). Babies without visual impairments are often in a seated position when reaching out to people and objects in their environment (Ferrell, 2011). It becomes the role of the EIVI professional, parents, and other interventionists to motivate the child with a visual impairment to reach, touch, and interact with compensatory targets in their surroundings. Some motivating items might include bright, colorful lights, sounds, preferred textures, or smells. The EIVI professional and family need to work collaboratively to find motivating targets for the child in order to encourage exploration, curiosity, and interest in their surroundings. This will ultimately combat the effects of inactivity, which is directly linked to low muscle tone.
Visual impairment limits opportunities during infancy for visual feedback of motor skills, making it difficult for children to practice and develop muscle tone (Wiener, et al., 2010). EIVI professionals and families need to intentionally provide opportunities for children to practice skills in order to develop muscle tone. Specific and detailed verbal information will help a child with a visual impairment orient to, and familiarize themselves with their surroundings. For example, “Wow! There is a cool toy next to your hand!” Children are unique, and the motivation to move and explore will differ for each child. Some children might be especially motivated to investigate sounds, others lights, and others smells or textures. Providing that motivator and encouraging movement will help the child to develop muscle tone and avoid the effects of hypotonia.
Young children with visual impairments may not have the motivation to move towards, or reach for objects and people due to poor vision and an inability to see their surroundings. It is vital that families provide frequent, intentional, and purposeful compensatory targets for their children to interact with in order to promote muscle development.
References
Chen, D. (2014). Essential elements in early intervention: Visual impairment and multiple disabilities. New York: AFB.
Ferrell, K. A. (2011). Reach out and teach: Helping your child who is visually impaired learn and grow. New York, NY: AFB Press.
Pogrund, R. L., Fazzi, D. L., & Lampert, J. S. (1992). Early focus: Working with young blind and visually impaired children and their families. New York: American Foundation for the Blind.
Wiener, W. R., Welsh, R. L., & Blasch, B. B. (2010). Foundations of orientation and mobility: Volume 1, history and theory. New York: AFB Press.