CVI: Impact of Light

Learn about the how light can be both a support and a barrier to access for people with CVI, observable behaviors and compensatory skills, general ideas for accommodations, and current research.

Written by: Rachel Bennett

Access the video transcript.

At Perkins, we are a gathering place of ideas. The CVI visual behaviors synthesize current research and build on the work of leading theorists in the field. CVI is a lifelong disability and we want to ensure that all individuals with CVI are fully understood. The CVI visual behaviors are an ongoing need, they can change and they can improve for some, but the need never goes away. No one area is separated from the other—the CVI visual behaviors are highly connected and all can impact the individual with CVI at any time.

What is the Impact of Light?

Light can be both a support and an area of difficulty for people with CVI, where it can either increase or decrease visual attention and recognition.

Some people with CVI may

Some people with CVI may demonstrate light sensitivity. They may 

There are specific indoor lights that my daughter does not prefer to have on. In her bedroom, she prefers a daylight color temperature bulb to be on as opposed to the overhead ceiling light. She uses this projected light from her desk lamp as a spotlight and does not want it directly on her.

Parent of child with CVI

What are some compensatory strategies related to the Impact of Light?

People with CVI have strategies and workarounds for so much in their daily lives. Light can be used as compensatory support, but some may also use compensatory skills when light is distracting, disorienting, or fatiguing.

Some people with CVI may:

If there was a bright lamp in a dim room, or if the TV was on with the lights off, that’s what would grab my visual attention. I would find myself staring at it, even if it hurt my eyes.  

Nai, adult with CVI

What are some look fors/questions when observing your child with CVI?

Observable behaviors may include: being distracted by light sources, avoiding light sources, increased attention or recognition with backlighting or task lighting, squinting or avoiding light of different spectrums.

When I read, I need to have a lot of light in the room and have frequent breaks in between, especially when I’m reading school books.”

Dagbjört, an adult with CVI, from Why Music is My Vision

What are some examples of adaptations and accommodations? 

All accommodations must be based on individual assessment. The following are meant to inspire and provide a general idea. Accommodations and instructional approaches must be student-specific. Access is individual. 

Some environmental considerations may include

Some considerations for materials or personal equipment may include

Find more examples from a guide to common CVI IEP accommodations in the CVI Now IEP Guide. 

I don’t like dark movie theaters. I can’t tell if someone is coming toward me. I look at all the exits, but I can’t map the space. I can’t tell where people are or where they’re going.

Albie, adult with CVI, from Albie’s CVI Perspective

Following the science

Connecting current research of the brain, our visual system, and CVI to better understand the CVI visual behaviors.

CVI Parent Perspective

“My son really loves his darkroom time. He needs this time to help him recover from visual and physical fatigue. He also has photophobia and never loved using a bright light box or brightly lit toys. On a bright sunny day, he relies more on his blindness skills because the bright sun and all the objects in the environment that reflect the sun can be disorienting. He does love to watch iPad videos but prefers a paper version of his adapted books during reading time. When he’s in the house, he needs medium light for eating and daily living tasks and hates it when he’s trying to do tasks in the complete dark. So light is not a simple notion; it can be both a support and a barrier to access.”


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Good, W. V., Hou, C., & Norcia, A. M. (2012). Spatial contrast sensitivity vision loss in children with cortical visual impairment. Investigative ophthalmology & visual science53(12), 7730–7734.

Jan. J. E., Groenveld, M., & Sykanda, A. (1990). Light-gazing by visually impaired children. Dev Med Child Neurology 32(9), 755-759.

Jan, J.E., Groenveld, M. and Anderson, D.P. (1993), PHOTOPHOBIA AND CORTICAL VISUAL IMPAIRMENT. Developmental Medicine & Child Neurology, 35: 473-477.

Lueck, A. H., & Dutton, G. N. (2015). “Intervention Methods: Overview and Principles.” A. H. Lueck & G. N. Dutton (eds). Vision and the Brain: Understanding Cerebral Visual Impairment in Children (pp. 497-536). New York, New York: American Foundation for the Blind Press.

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Roman-Lantzy, C. (2018). Cortical Visual Impairment: An Approach to Assessment and Intervention. 2nd ed., New York, NY: AFB Press.

Salati, R., Borgatti, R., Giammari, G., & Jacobson, L. (2002). Oculomotor dysfunction in cerebral visual impairment following perinatal hypoxia. Developmental Medicine & Child Neurology, 44(8), 542-550. doi:10.1017/S0012162201002535

Wu Y, Hallett M. Photophobia in neurologic disorders. Transl Neurodegener. 2017 Sep 20;6:26. doi: 10.1186/s40035-017-0095-3. PMID: 28932391; PMCID: PMC5606068.

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