A new digital assessment tool supported by California for early identification of children prone to becoming dyslexic helps highlight efforts by Illinois optometrist Deborah Zelinsky OD to secure government funding for mandatory eye-ear integration testing even before children enter school.

The new evaluation tool, developed by the University of California San Francisco and announced this year (2022), would provide a validated, web-based option for determining learning weaknesses in children long before they enter third or fourth grade when dyslexia-related issues become much more obvious. The State of California has reportedly been considering the program for significant budgetary support and introduction into the state’s public schools in 2023.

“What the University of California has created demonstrates how, with the right federal and state support, we can find ways to intervene earlier in helping children whose visual processing skills are slow to develop of fail to fully develop,” says Dr. Zelinsky, founder and executive research director of the Northbrook, Illinois-based Mind-Eye Institute. “Early intervention would help significantly reduce the number of children who are now categorized as ‘learning deficient’ and placed in special-education classes.”

Dr. Zelinsky contends that some learning problems, like dyslexia and attention deficit hyperactivity disorder, are oftentimes the result of visual processing challenges due to a lack of coordination among a person’s sensory systems. Sensory mismatches affect processing of motor control, often making reaction times slower in children. “Most states have laws that mandate evaluation of a child’s eyesight and hearing separately, but such testing does not determine how well the two sensory systems work together,” says Dr. Zelinsky, who has research interest in dyslexia. 

Like eye-hand coordination, synchronization of sight and sound does not fully develop in a child until about age 7 or 8.  Oftentimes, learning expectations of children at earlier age levels surpass their developmental stage. Similarly, a child’s struggles to learn reading after age 8 can be symptomatic of under-developed visual-hearing linkage, says Dr. Zelinsky. 

Years ago, reading was not heavily emphasized until the third grade, when children had a more solid eye-ear connection. Now, even preschoolers are being taught how to recognize sight words (visual development) and how to sound out words (auditory development). If the child has not linked the two systems, he or she will likely either be a poor speller or be unable to sound out words easily, Dr. Zelinsky states.

Difficulties in spelling or pronouncing words, processing, and comprehending written text, inability to hear differences or similarities in sound, and trouble reading aloud are among  hallmark manifestations of dyslexia, “but these symptoms are far from being the whole story,” Dr. Zelinsky states.

An article appearing in a 2018 edition of PLOS ONE (10.1371/journal.pone.0208923) indicates audiovisual processing difficulties are what contribute to dyslexia. “Dyslexia may be a visual processing disorder at its core, although more research is needed to better understand what brain processes are implicated,” Dr. Zelinsky says in commenting on the research.

Visual processing involves a complex network of communication signals between the central nervous system, which includes the brain and spinal cord, and the eye’s retina and optic nerve. Indeed, the retina is composed of brain tissue and acts as a primary portal for information to the brain. Environmental signals in the form of light pass through the retina and are converted into electrical signals that propagate through neurons and interact with critical brain structures. 

Retinal signals interact not just with the visual cortex (for eyesight) but affect other, significant regions of the brain as well, like the hypothalamus and brainstem. The implication is that stimulation of the retina can impact regulation of basic physical, physiological, and even psychological processes, including motor control, posture, emotions, and perception. Perception is based on individual experiences and sensory integration and is a key factor in decision-making.

The Mind-Eye Institute is world-renowned for its understanding of visual processing and for unique approaches to helping patients whose visual processing either has been disrupted by traumatic brain injury, concussion, stroke, and neurological disorders, or has never fully developed, resulting in learning problems.

“Using highly individualized, therapeutic brain glasses, lenses, prisms, and filters, we can stimulate the retina by controlling the amount, intensity and angle of light that is dispersed on it. In that way, we are often able to maximize visual processing capabilities, create a stable balance between hearing and eyesight localization, and enhance patient perception of the surrounding environment to improve communication,” Dr. Zelinsky explains.

She points to a November 2021 study in The Journal of Neuroscience (10.1523/JNEUROSCI.1232-21.2021) where investigators suggest dyslexia is a visual processing disorder that affects more than reading. Children with dyslexia “differ in their behavioral responses to visual information, particularly when required to pool dynamic signals over space and time…We investigated which processing stages are affected in children with dyslexia when performing visual motion processing tasks…[and determined these individuals] tend to be slower to extract sensory evidence from global motion displays,” the scientists write. [Our] findings “further our understanding of atypical perceptual decision-making processes in dyslexia.”

An article published in 2020 in PLOS Biology (10.1371/journal.pbio.3000833) indicates that stimulation of the brain in the auditory cortex region can improve “phonological processing and reading accuracy” in patients with dyslexia. The scientists applied transcranial alternating current as their method of stimulation. However, the findings corroborate the successful work of the Mind-Eye Institute in stimulating the retina, using light, to effect changes in the brain and reduce learning deficiencies, including dyslexia.

Meanwhile, scientists, who authored a study appearing in Current Biology (https://doi.org/10.1016/j.cub.2009.08.014), report findings that developmental dyslexia is a different type of disorder in Chinese individuals. “Unlike English, written Chinese maps visually intricate graphic forms (characters) onto meanings; pronunciation of Chinese characters must be rote memorized. This suggests that, in Chinese, a fine-grained visuospatial analysis must be performed to activate characters' phonology and meaning; consequently, disordered phonological processing may commonly co-exist with abnormal visuospatial processing in Chinese dyslexia,” the researchers write.

Dr. Zelinsky concludes that “every study advancing our knowledge of learning disorders takes us one step closer to their eventual resolution. As a researcher and clinician, my ultimate goal is to one day find an approach or technique that will eradicate dyslexia completely.”