Eyes Serve as ‘Point of Entry’ for Assessing Brain Function

“The eye can be used as point of entry for assessment of brain function,” Deborah Zelinsky, OD, founder of the Northbrook, Illinois-based Mind-Eye Institute, told an international group of scientists, meeting in Los Angeles in mid-July. For that reason, “optometrists can often detect early disease processes by evaluating how the eye’s pupil responds to changes in light.”

Because the retina is composed of brain tissue and functions as part of the body’s central nervous system, “all body processes connect with the eye, including the endocrine, neurologic, psychiatric, respiratory, musculoskeletal, and gastrointestinal systems,” she indicated during a panel presentation. “Light entering the eye affects brain activity, which influences activities in the body’s organs. Indeed, retinal processing is involved with multiple systems that affect the quality of a person’s life.”

Retinal processing is one part of visual processing. Visual processing refers to that almost-instantaneous ability of the brain to take in multiple sensory signals (from eyesight, hearing, smell, taste, and touch) at all levels – unconscious, subconscious, conscious; meld them with one’s internal sensory signals; and then process the information to end up with a response. Before the responses occur, there are reflexes at an unconscious level, influencing the responses.

Dr. Zelinsky was speaking at the 17th and 18th World Congresses of the Society for Brain Mapping and Therapeutics (SBMT), an organization for which she serves as a board member. As head of the organization’s optometry/ophthalmology subcommittee, she invited more than 50 different individuals to present in 12 different sessions during the four-day period of the conference.

Each day of the conference had a theme, ranging from new research in optometry and ophthalmology to the future role of eye care in overall health. Speakers varied from strictly visual researchers representing the Bascom Palmer Eye Institute and movement specialists using Anat Baniel’s NeuroMovement method to actual stroke “thrivers” – not “victims” — as noted in Claudia Mason’s recounting of vertebral artery dissection.

Because of lingering COVID-19 pandemic issues, many researchers, including Dr. Zelinsky, chose to join the conference virtually. Dr. Zelinsky’s participation, however, proved especially unique. While seated in her suburban Chicago office, she remotely wheeled a robot, armed on top with an electronic tablet, inside the Mind-Eye Institute’s conference booth and throughout the program hall, virtually visiting other exhibits and interacting with scientists who were present on site. Her use of high-end technology was even mentioned in a Los Angeles Times article about the return of conventions after the loosening of COVID-related restrictions.

Throughout her presentations, Dr. Zelinsky reiterated a key theme: retinal processing plays a critical role in the integration of various senses, including eye-ear coordination, as well as the regulation of physiological processes, which in turn influence motor control, biochemical activity, and perception.

“The retina not only transmits environmental signals through eyesight at a conscious level but also from luminance (external light) and movement that disperses across the retina at a subconscious level. Concurrently, the retina receives feedback signals from the body. This continual process of feeding forward sensory signals to the brain from the environment and then receiving feedback signals from various brain structures makes the retina a two-way portal for influencing and monitoring thought processes and body functions, including posture, movement and motor reflexes,” Dr. Zelinsky stated.

She described the retina as a structure containing approximately 126 million light-sensitive receptors. “Input from the receptors moves through a sophisticated filtering system, which compresses the information into about 1.2 million exiting signals. This compression occurs by having information filter through five different classes of neurons over a span of a half millimeter of thickness. These signals leave the optic nerve and branch off into many brain pathways. In fact, the retina connects with numerous systems other than eyesight, including structures in the brain’s cortex, cerebellum, and limbic system, as well as midbrain and brainstem.”

Throughout her 35 years of optometry work, Dr. Zelinsky has devoted herself to neuro-optometric rehabilitation and the development of new methods for assessing brain function, with emphasis on the often-untested linkage between eye and ears. Her patented research in retinal processing and in novel uses of retinal stimulation has been described in publications and courses worldwide. She currently works with the Blind Service Association in Chicago to enhance visual skills, such as visualization and subconscious awareness, that remain in those who have lost the ability to see details.

Variation in the amount, intensity, and angle of light as it passes through the retina triggers “different reactions and responses that activate various types of eye movements and reflexes,” she said. Underlying brain injury or disease is oftentimes implicated when a patient’s retinal processing, including pupil response, is dysfunctional.

Dr. Zelinsky and her Mind-Eye Institute team have achieved significant clinical successes and worldwide recognition in using therapeutic eyeglasses (Brainwear®), lenses, and other optometric interventions to help patients redevelop visual processing skills during recovery from brain injuries, neurological disorders, including stroke, as well as in building new processing skills in patients labeled as having “learning differences.”

She told scientists during the SBMT conference that “optometrists can have a positive impact on perceptual impairments by enhancing assessment of a patient’s peripheral eyesight, testing eye-ear connections, and prescribing therapeutic glasses that modify light entering the eyes to enhance comfort and reduce symptoms. People with brain injuries or learning problems need additional testing above and beyond central eyesight evaluation.”

Deborah Zelinsky, O.D.
Founder, Executive Research Director
Mind-Eye Institute