Educators and Therapists
Teaching and Learning in Phase III1
Published with permission from author, Dr. Christine Roman-Lantzy.
In Phase III CVI, the goal is to refine the CVI characteristics. Though some of the behaviors associated with the CVI characteristics will have resolved, the refinement of the characteristics is an ongoing process of improving ventral stream functioning. By helping the student to identify salient visual features and items in a complex setting, he will develop a more fine-tuned ability to discriminate details of images and symbols, both up close and at greater distances. (178)
To the untrained eye, a student who has reached Phase III may not appear to have CVI because his visual responses will look more and more like someone with typical vision. However, CVI is a lifelong condition. While an individual with Phase III has greatly improved vision and is able to sustain visual attention throughout the day, he remains visually impaired. He will continue to need adaptations to materials and specialized instruction to access and engage with the visual world. (178)
It is not typical for a student to score above a 9 on the CVI Range. CVI characteristics will not fully resolve. In fact, complex materials will remain challenging and crowded, novel environments may be disorienting. Lower field deficits usually persist, as well. (188)
“Individuals with Phase III CVI have attained significant levels of functional vision, but it is critical to recognize that they are still affected by an underdeveloped ventral visual stream. Although improvements in visual functioning are expected to occur across the span of the CVI Range, in Phase III the progress may be slow, and even though an individual's functional vision has significantly improved, aspects of the characteristics of CVI remain active well into Phase III.” 2
Individuals in Phase III CVI continue to demonstrate behaviors associated with the CVI characteristics.3 These challenges can include:
- inability to visually discriminate, recognize, or identify novel materials or environments;
- inability to detect targets at distances beyond 10-15 feet away;
- visual field differences, especially lower field function;
- inability to discriminate facial features;
- occasional latency;
- need for detailed targets to be paired with light;
- need for color to be used to highlight materials or environments; and
- inability to use a visually directed reach when targets are presented against a complex array.
Intervention Strategies for Phase III CVI
How can you help a student manage an increasing level of complexity in his day-to-day life? In increments. Gradually add background detail to two-dimensional materials until the student can identify salient features and details in a presentation without adaptations. Color, movement, and backlighting will still be helpful ways to highlight details in the midst of complexity. (188)
For a student in Phase III, the complexity of an environment will still affect his ability to locate items and their details. Gradually increase the complexity of a setting, much like one would increase the complexity of two-dimensional materials.
Due to continued difficulties with lower visual fields, students with Phase III benefit from instruction from a Certified Orientation & Mobility Specialist to learn how to navigate areas with descending steps, drop-offs, or surface changes, and to navigate through new settings. (189)
Instruction in Phase III generally has two big themes: instruction in identification of salient visual features and discriminating targets against increasing amounts of background complexity. Salient visual features are the defining elements that distinguish one target from another. Comparative thought is the process of considering the similarities and differences between two or more objects. To be able to discriminate, recognize, and identify a target even when it appears in a complex and crowded array, requires the recognition of salient features and comparative thought.
CVI and Literacy
Salient Features
1Content on this page from Roman-Lantzy, C. (2018) Cortical Visual Impairment: An Approach to Assessment and Intervention. 2nd ed. pp. 178-189. New York, NY: AFB Press.
2,3Roman-Lantzy, C. (2019). Cortical Visual Impairment: Advanced Principles. Louisville, KY: APH Press, 12.