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Rolling Ridesharing Van Tests My Visual Processing At Different Levels

Updated Exams Needed to Assess Each

My reactions to a recent near accident as I was trying to enter a vehicle later prompted me to reflect on how our brains respond to the world at so many levels and why the multiple tests we conduct at the Mind-Eye Institute are critical to determining each patient’s unique visual processing deficiencies and needs.

I was with a group of four entering a ridesharing vehicle. Two people were already seated, one was waiting behind me, and I was literally stepping into the van when the driver started to pull away. My immediate action was to scream and grab the door tighter – simply hold on as best I could. It was an unconscious, instantaneous, reflexive response. Sensory processing then kicked in at a subconscious level as I became more aware of my environment – seeing and feeling the van moving. Finally, my perception – and understanding — of the incident rose to consciousness, and I was able to start yelling to the driver, “Stop!” Luckily, no one was hurt, and the primal (non-conscious) screams were loud enough to cause the driver to hit the brake.

Of course, all these levels of perception – from reflex to awareness of the environment to consciousness – occurred within microseconds. As the renowned cognitive neuroscientist A.R. Luria pointed out in his many publications, the brain functions simultaneously on multiple signaling circuits at different speeds.

Research has demonstrated the retina is a piece of brain tissue, which is part of our body’s central nervous system. It not only sends the brain 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 through informational brain pathways. This continual process of feeding forward sensory signals to the brain from the environment and 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, motion, and, of course, motor reflexes, such as my screaming and tight gripping of the moving vehicle’s door.

Each of our eyes contains 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 signals. This compression occurs by having information filter through five different classes of neurons over a span of a half millimeter of thickness. (Typically, there needs be only one neuron carrying information – even over long distances.) 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.

But back to the rolling ridesharing vehicle.

My retinal processing brought me from unconscious reflex through subconscious awareness of what was happening around me to conscious initiative — yelling coherently at the driver to stop the vehicle. A very normal series of reactions. Indeed, in scientific terms, visual processing refers to that almost-instantaneous ability of the brain to take in external 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.

The ability to visualize and process what we see – and hear — enables us to understand. We make decisions and projections on the basis of this understanding. It was at a reflex level that my body realized the ridesharing van was moving and took the necessary action, tightening my grasp on the vehicle’s door and causing me to scream at a primal level. The more coherent shouting directed at the driver came later, after conscious processing occurred.

Unfortunately, patients who have sustained a traumatic brain injury, concussion, or stroke; suffer from a neurodegenerative disease; or struggle with learning disorders oftentimes exhibit processing deficits that affect their ability to respond normally to the world around them. Their senses, especially eyesight and hearing, are not in synchronization; they have difficulty visualizing auditory space. Where is that sound coming from?

The Mind-Eye Institute applies new scientific discoveries to test patients’ retinal processing capabilities at various levels and prescribes for comfort. We accomplish this by working to resynchronize perception of eyesight and hearing and developing new informational pathways in the brain through manipulation of light on the retina. Our tools include lenses, filters, and prisms highly individualized to address each patient’s needs.

Admittedly, I have just presented a whole lot of science flowing from one life episode that most people would likely have long forgotten by now. But I did so, realizing that the processing of moving targets is so necessary in today’s modern society with its mobile phone screens, movie and video-game special effects, highly trafficked streets, and required scanning of rolling information on computer displays and GPS systems.

Properly functioning peripheral eyesight is necessary for normal visual processing to occur.

The time is now to adopt advanced scientific practices that can help make life better for thousands of patients — whether or not ridesharing vans are part of your future!

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