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Strabismus
The developmental optometrist sees strabismus very differently from an ophthalmologist. Typically, strabismus is treated surgically by ophthalmologists, a “hardware” approach, whereas The Center for Visual Management views strabismus as a neural “software” disorder. Our treatment method is non-surgical and driven by the brain’s plasticity to change.
Strabismus is not a problem with the eyeball itself, but rather a neural dysfunction for which strabismus is a symptom. It is an adaptation precipitated by the conflict in the central nervous system (CNS). When there is a lack of synchronization between what we perceive and our concept of the world, the response of the visual cortex is to diminish perception in an effort to facilitate conception. This leads to a loss of three-dimensional space and eventually a tunneling of our visual world.
Motion Sickness/ Vertigo
Neuroscientific literature has identified that the visual system has two visual pathways referred to as "M" and "P". The "M" pathway, or our ambient vision, is concerned with movement and depth perception. The "P" pathway, which is referred to as focal vision, is concerned with form and color. The "M" pathway is generally considered to be crucially involved in motion processing. Individuals who are unable to resolve field differences in binocular rivalry of the "M" pathways present different levels of motion sickness.
The effects of yoked prism lenses on the "M" pathways reduce the frequency of eye movements resolving the field differences in binocular rivalry. This affects the feedback cycles that influence visual and vestibular processing. While vestibular input can alter visual processing (in motion sickness, the way in which a disturbance of the vestibular system in the inner ear causes disturbances in visual perception), the reverse is also true: changes in the visual system can influence the vestibular system. At The Center for Visual Management, we have found that directive yoked prisms can reduce abnornal saccadic eye movements, which in turn stabilizes the vestibular system and eliminate the symptoms associated with motion sickness and vertigo.
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Autistic Spectrum Disorders
While impaired vision is not the only neurological problem spectrum children exhibit, the dominant role of the visual system in learning and development makes impairment of this visual system particularly deleterious. The child with autism cannot use his or her visual system efficiently, and must depend on more rudimentary senses of touch, smell or taste.
Autistic children display many of the symptoms associated with vestibular involvement. It permeates most of the literature in other disciplines. Although many autistic children cannot verbally describe how they feel, it becomes quite apparent from their actions and in performance of vision and movements. Although their visual system often cannot be measured or verbalized in the same manner as other sighted individuals there is a way to observe and change their performance. At The Center for Visual Management, the Kaplan Non-Verbal Battery, which involves pre and post tests, utilizes ambient prism lenses to evaluate their ability to change posture, attention and disposition.
The concept that vision is learned plays a significant role in modifying autistic behavior. What one learns from experience, one can change by experience. In the visual management of autism, performance enhancing lenses combined with a developmentally designed sequence of movement procedures allows the autistic child to experience a revised interaction with their world. The child moves through stages of awareness, attention, and automicity of information processing. The neural system responds by regrouping their synapses. Can we say then that the child is no longer autistic? Not quite, although he or she experiences a higher level of performance, improved behavior, and many gain language with reduced symptoms that define the label.
Tunnel Vision/Depth Perception
Ambient vision is the processing of local motion cues into global motion percepts. Global motion computation is not trivial because real world scenes contain multiple overlapping objects which can be moving in different directions. When the task becomes overwhelming for the brain to manage one adaptation is “tunneled" vision.
"Tunnel vision” is the brain's survival approach to reduce its space/world to what it can control. Tunneled vision, or compressed vision is when the field of vision is constricted to a relatively small field. Focusing only on what one see’s in this “tunnel” people with compressed vision view the world in two-dimensions and present dysfunction in judging distance and/or motion. In some cases the world appears to be falling apart on them.
Individuals with tunnel vision appear asymptomatic. They block out what they cannot control. Their personality is marked by tenacity, highly organized, and singlehandedness. In many cases this is their inherent perceptual style, meaning it may begin in infancy and childhood. In other cases, individuals who have a "global"
perceptual style that is dysfunctional may overcompensate and function in a tunnel. These individuals are highly symptomatic, displaying problems in organization, emotion, and asthenopic symptoms, such as stress, headaches, fatigue, and stomach problems. A visual management approach to the former is an eccentric expansion of their tunnel, allowing them more information to process in far less time. The latter approach is through global integration of space world and figure/ground organization.
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