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 visual attention?
Visual attention is the ability to look at something or when the eyes fixate on an object or target in the environment. Visual attention is the prerequisite for visual recognition.
The visual system allows the brain to
- visually search for targets among competing distractors,
- attend to this target while ignoring other stimuli,
- maintain focus,
- and then match the target to our visual library to support the speed and efficiency of recognition.
When searching for an object, it’s not just about where to look but also where not to look. The brain has to keep track of what it’s looking for and ignore information that is not relevant. Visual attention is the starting point that enables us to perceive the world around us, and there is no visual recognition without visual attention.
People with CVI can have a wide spectrum of visual attention skills, from little visual attention to sustained visual attention abilities. For many with CVI, internal and external stimuli can impact and disrupt visual attention. And for some, visual attention can only occur when there are no distractions from other sensory inputs (noise, distracting movement, clutter, disorienting environmental light, and internal factors).
Sometimes, if things are extra challenging, I might lose my vision for a couple of minutes.
Dagbjört, adult with CVI
CVI can have a profound impact on visual attention, making many aspects of visual attention difficult or near impossible, including:
- fixation and shifting eye gaze
- using vision with competing sensory stimuli
- controlling where you want to look
- filtering out visual clutter to search and find an item
- establishing and sustaining eye-to-object contact
Visual attention can vary, sometimes significantly, depending on a lot of factors, which may include:
- visual fatigue
- noise level in the environment
- level of clutter at near or at a distance in the environment
- over stimulation
Looking does not mean understanding—but just because visual attention is not present or not sustainable for some with CVI, it does not mean that learning does not continue. Even when all the right factors are in place, and the person with CVI can look at something, this does not always equate to recognizing what’s being looked at. It’s important that when we assess and evaluate students with CVI, we do not confuse looking with fully seeing and interpreting the visual world. It’s important to make sure that CVI assessment doesn’t solely focus on the ability to look at something but deeply looks at both visual attention and recognition, and the compensatory skills that the student uses to support understanding (e.g., memory, color-coding, adulting prompting, tactile and auditory skills, context of the place or task).
My child has intermittent or short visual attention for anything unfamiliar.
What are some compensatory strategies related to visual attention?
People with CVI have strategies and workarounds for so much in their daily lives. When environmental and internal factors make visual attention difficult or near impossible, many with CVI rely on their compensatory skills for access.
Some people with CVI may rely on:
- Tactile exploration of items and the environment
- Sound cues from objects, people, and the environment
- Verbal cues that support establishing visual attention on a specific target
- Color to draw one’s visual attention to familiar landmarks
- Context to help fill in the gaps in vision and cue past experiences and memory
- Predictability and organization to locate items, people, and places in the environment
Vision alone never ‘came into focus’ by itself. It had to be buttressed by something non-visual
Nai Damato, adult with CVI, The CVI Perspective
What are some look fors/questions when observing your child with CVI?
- What factors increase, decrease, or have no impact on visual attention?
- Does the child with CVI look at objects? How is visual attention impacted by all visual presentations (color, clutter, familiarity, etc.)?
- Is visual attention established immediately, with a delay, or not present? Are visual fixations present, brief, or sustained? How is this impacted by all visual presentations (color, clutter, familiarity, etc.)?
- Does the child visually attend to faces? How is this impacted by familiarity or visual/auditory distractions?
- Is visual attention maintained while reaching or pointing? How is this impacted by all visual presentations (color, clutter, familiarity, etc.)?
- Is visual attention present and equal across all visual fields?
- To what extent do multiple sensory inputs affect visual attention? Is the child able to visually attend while using auditory or tactile skills?
- To what extent does color (saturation, brightness, single color, or multicolor) affect visual attention (color increase, decrease, or have no impact)?
- To what extent does lighting (backlighting, lighted object, target lighting) impact attention to a task? How do environmental lighting levels (bright, dim) impact attention to the task?
- Does movement support visual attention to tasks/materials? Is the child distracted by movement in the environment?
Visual inattention was as if the visual world was suspended in some other dimension, often somewhere in between waking reality and the dream world, but always slightly beyond what my fingertips could touch. I could almost get there, but still not dive into it fully, like waking up from a dream that lies just beyond your conscious memory on a groggy morning. Vision existed in this liminal space of reality-unreality.
Nai Damato, adult with CVI
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.
The main goal of accommodations and adaptions for CVI is access to learning. We can provide supports to help make visual attention less fatiguing AND provide supports and instruction that do not require visual attention to access learning. Many with CVI need both types of support: visual and other sensory channels (auditory, kinesthetic, and/or tactile). Remember, vision is not reliable 24/7, so what accommodations and adaptations are required for the student with CVI to access their learning throughout the entire day? Supports are not a hierarchy, meaning visual accommodations are not the be-all-end-all for some with CVI; sometimes, tactile and auditory supports need to take the lead. It’s about balance and what works best for the individualized needs of the person with CVI.
Adapt the learning environment
- Reduce visual clutter in the learning space. For example, use a black trifold to create a clean background when presenting learning materials or find a learning space that has at least two blank walls so the background clutter does not interfere with trying to visually attend to the learning material.
- Reduce noise and distracting light (overhead, from windows) and movement (high traffic areas, peers passing by, or a group working nearby).
- Supportive positioning: Your child should be physically supported for learning tasks and activities. This may include a wheelchair, stander, or other equipment adaptations required (armrests, footrests, stool) and in any other position deemed safe by your physical therapist and occupational therapist.
- Leverage color and contrast. Use bright, bold colors to support visual attention in the environment. The incorporation of color should be strategic—adding too much color to the environment can increase the impact of crowding. For example, bright blue tape around the rim of a container, green tape on handrails, or yellow on the student’s chair. Make sure color supports increased contrast to help the target pop and stand out.
Adapt the learning task
- Know the most accessible learning media. For some with CVI, they are only able to visually attend to real objects; for others, they can also look at pictures, photographs, and print. But even attending to two-dimensional materials for too long can be fatiguing for many with CVI. What type of learning material is most visually accessible? Remember, the student must have a way to access their learning using other sensory channels (auditory, kinesthetic, tactile) so they have full access to their learning at all times.
- Reduce visual clutter and crowding. Simultaneous visual information may disrupt visual attention. If the learning task includes the use of vision, make sure items are presented either one at a time or with the number of items that is the assessed threshold for the student. For example, no more than three or four at a time. Presentation is typically task-dependent.
- Leverage color and contrast. Use bright, bold colors to support visual attention. The incorporation of color should be strategic when adding it to learning materials. Color can draw visual attention to details on an object or photograph. Color-coding math problems can help reduce the visual search for important information and follow along in solving an equation. Make sure the color supports increased contrast to help the target pop and stand out. The point is to reduce visual search so maintaining visual attention is not so fatiguing.
- Intentional use of light. Use backlit devices or task lighting to support visual attention. For example, shine a flashlight on an item presented with other items to support initial focus. For some with CVI, a tablet offers backlighting to support the visual attention to two-dimensional pictures and images. Remember, some with CVI have light sensitivity, so too much light can be fatiguing.
- Consider the impact of motion. Sometimes, slow methodical movement of an object can support visual attention. But some with CVI visually avoid or miss fast-moving objects.
- Present materials in accessible visual fields. Does your child see best at left, right, or central? Place items on a slant board with a magnet or velcro board if your child has difficulty with their lower visual field. Raise items to eye level using a dark color plain box. Learning materials should be positioned in the most accessible visual field (right, left, upper, lower)—use assistive items (i.e., slant board, book stand, tablet stand).
- Allow the student to focus on one task at a time (i.e., writing, listening, or speaking). If they need to listen, expect them to only listen. If they need to visually attend to something, do not expect them to listen simultaneously. Offer a prompt, then stop talking and observe the student’s actions. Continue ongoing assessment and progress monitoring in this area.
Full access to learning (because vision is not reliable 24/7)
- Multisensory learning to ensure active engagement: Provide multiple opportunities and various sensory channels for students to learn about new concepts and show their learning. We have a wide range of design tools available to meet the individualized learning needs of each student with CVI—auditory, kinesthetic, tactile, and visual. Use real objects, manipulatives, experience stories, active learning approaches, story boxes, and hands-on activities.
- Direct and explicit instruction to develop rich concepts in all areas of learning. Many foundational skills for literacy and numeracy come from being able to visually attend to the surrounding environment (incidental learning). Educators and providers must provide direct instruction in all the skills and concepts needed to master a learning goal.
- Create a strong sensory foundation for concepts in the natural environment (people, objects, actions, and places) to ensure that communication symbols (tangible, auditory, visual) about these concepts are meaningful. Link sounds and tactile input to visual events. Use language to connect sensory experiences, help build connections, and label events, feelings, and situations.
- Autonomy, choice, and advocacy. Create systems that scaffold self-advocacy and support agency for the student. Provide choices for how they want to consume the information, apply their skills, and show what they want to know. Making space for choice and autonomy means having multiple supports and access points available. We have to evolve with the student, observe constantly, and collect data. We have to always reexamine the environment, instructional approach, and learning tasks and materials.
Find more examples from a guide to common CVI IEP accommodations in the CVI Now IEP Guide.
My son is better able to visually attend to something if he engages his tactile system first. His teachers have him do a tacitle warm-up before a visual task and he often needs to continue to hold something in his hands as he looks. But then after 5-8 minutes of looking he needs a break from using his vision.
Rachel, CVI parent
Following the science
Connecting current research of the brain, our visual system, and CVI to better understand the CVI visual behaviors.
- Visual attention is the “ability to prepare for, select, and maintain awareness of specific locations, objects, or attributes of the visual scene (or an imagined scene)” (Deyoe, 2002). This cognitive process allows us to “selectively process the vast amount of information we are confronted with every day. Since the capacities of the perceptual system are limited, focusing on a certain aspect of the visual field enables us to prioritize relevant information and ignore irrelevant information” (Lockhofen and Mulart, 2021).
- Visual attention can be reflexive (automatic, spontaneous) or through intentional effort (Deyoe, 2002). We use a combination of eye movements—saccades (moves rapidly across the scene) and fixations (gaze is still). Analysis of the scene is “performed during fixations” (Johnson, 2013). These fixations, or visual attentional control, can be “based on either stimulus factors, such as the salience of an object or region, or goal relevance, such as the match between an object and the target being searched for” (Vecera, 2014).
- The brain uses a circuit to filter out distracting sensory information to establish and maintain attention. The article, To Pay Attention, the Brain Uses Filters, Not a Spotlight, summarizes new research on attention:
- “The full circuit, they found, goes from the prefrontal cortex to a much deeper structure called the basal ganglia (often associated with motor control and a host of other functions), then to the thalamic reticular nucleus (TRN) (a thin layer of inhibitory neurons), and the thalamus, before finally going back up to higher cortical regions. So, for instance, as visual information passes from the eye to the visual thalamus, it can get intercepted almost immediately if it’s not relevant to the given task. The basal ganglia can step in and activate the visual TRN to screen out the extraneous stimuli, in keeping with the prefrontal cortex’s directive.”
- Posner Model of Attention: Selective attention is the ability to search and find, sustained attention is the ability to maintain focus, and divided/dual attention is the ability to simultaneously attend to multiple things or types of stimuli (e.g., look and listen, handiwork and talk/watch TV, etc.). Attention is a multilevel selection process. (Das, et al, 200; Bauer, 2022).
- Damage to the parietal or occipital lobes can cause difficulty with visuospatial attention, sustained attention, selective attention, and visual search, which allows us to focus and filter the visual information world around us, and only focus on the important stimuli.
- Children with impaired visual attention present a “characteristic symptom complex,” which includes “difficulty seeing something pointed out in the distance, disability identifying a well-known person in a group, problems finding an item of clothing in a pile, and inability to find a chosen toy in a toy box without separating all the toys out.” (Das, et al., 2007)
- Visuospatial neglect, or visual inattention, is the difficulty detecting or acting upon visual stimuli on one side of space. This is different from visual field loss in that full visual fields are available, but the brain does not give the attention needed to be aware of visual stimuli in a specific visual area. The person with CVI may behave as if half of the space on one side does not exist. For example, if there is damage or interruption to the right posterior parietal lobe, there may be visual neglect or inattention to the left-hand side. Increased clutter and visual stimuli density can make visual neglect more severe (Nijboer and Stigchel, 2019).
- Damage to the dorsal visual stream can cause difficulties with spatial perception, visual attention, perception of movement, visually-guided reach, accurately and safely walking around obstacles, and distinguishing between multiple objects when presented with an array. Dorsal stream dysfunction contributes to difficulty with visual attention in the presence of competing stimuli: leads to distress in crowded and noisy locations, inability to find an object in clutter or a friend in a group (Chokron, Klara, & Dutton, 2021).
- Serial processing is scrutinizing one piece of information at a time when there is more sensory information to take in, while parallel processing is being able to process many elements of a visual scene at the same time. Serial processing is a less efficient form of visual search. Dr. Lotfi Merabet discusses that with an increased visual load, individuals with CVI have to grind it out (serial processing), as opposed to having that instantaneous capture of information we see with a really efficient visual system. When additional sensory input is added to an already overloaded and overtaxed visual system, things will start to shut down.
- Simultanagnosia is the inability to perceive a whole scene, environment, or picture; the inability to perceive more than one item at a time. Individuals with CVI might focus on one small part of a scene and miss another (larger) part entirely. Learn more about simultanagnosia. Damage to the parietal or occipital lobes can cause difficulty processing simultaneous visual information and difficulty shifting gaze between elements of a scene.
More resources to explore:
- Atkinson, J (2017). Visual Brain Development: A review of “Dorsal Stream Vulnerability”—motion, mathematics, amblyopia, actions, and attention. Journal of Vision, 17(3):26. doi: https://doi.org/10.1167/17.3.26.
- Braddick, O. and Atkinson, J. (2011). Development of human visual function. Vision Research, 51 (13), 1588-1609. https://doi.org/10.1016/j.visres.2011.02.018
- Banich, M.T. and Compton, R. J. (2018). Cognitive Neuroscience. Cambridge, United Kingdom: University Printing House.
- Bennett, C. R., Bauer, C. M., Bailin, E. S., & Merabet, L. B. (2020). Neuroplasticity in cerebral visual impairment (CVI): Assessing functional vision and the neurophysiological correlates of dorsal stream dysfunction. Neuroscience and biobehavioral reviews, 108, 171–181. https://doi.org/10.1016/j.neubiorev.2019.10.011
- Chokron, S. & Dutton, G. N. (2016). Impact of cerebral visual impairments on motor skills: Implications for developmental coordination disorders. Frontiers in Psychology 7(1471), 1-15.
- Chokron, S., Klara, K., & Gordon D. (2021). Cortical Visual Impairments and Learning Disabilities. Frontiers in Human Neuroscience 15, 573.
- Das, M. Bennett, D. M., & Dutton, G. N. (2007).Visual attention as an important visual function: an outline of manifestations, diagnosis and management of impaired visual attention. British Journal of Opthalmology 91, 1556-1560.
- Dutton, G. & Lueck, A. (2015). Vision and the Brain: Understanding Cerebral Visual Impairment in Children. New York, New York: American Foundation for the Blind Press.
- Deyoe, E. (2002). Occipital Lobe, Editor(s): V.S. Ramachandran, Encyclopedia of the Human Brain, Academic Press, Pages 677-715.
- Johnson, M.H. (2013). Chapter 11 – Theories in Developmental Cognitive Neuroscience, Editor(s): John L.R. Rubenstein, Pasko Rakic, Neural Circuit Development and Function in the Brain, Academic Press, Pages 191-205.
- Lockhofen, Denise and Mulert, Christopher. Neurochemistry of Visual Attention. Frontiers in Neuroscience, vol 15, 2021, https://www.frontiersin.org/articles/10.3389/fnins.2021.643597
- Prieler, T., Wood, C., & Thomson, J. M. (2018). Developing a visual attention assessment for children at school entry. Frontiers in Psychology 9(2496), 1-14
- Roman-Lantzy, C. (2018). Cortical Visual Impairment: An Approach to Assessment and Intervention. 2nd ed., New York, NY: AFB Press.
- Vecera, Joshua D. Cosman, Daniel B. Vatterott, Zachary J.J. Roper. (2014). Chapter Eight – The Control of Visual Attention: Toward a Unified Account, Editor(s): Brian H. Ross, Psychology of Learning and Motivation, Academic Press, Volume 60, Pages 303-347.
- Zihl, J., & Dutton, G. N. (2015). Cerebral Visual Impairment in Children: Visuoperceptive and visuocognitive disorders. Wien: Springer.