Vision has often been depicted as a ‘pyramid’, with core functions and systems arriving early in development (the ‘base’) and other more advanced behaviours and skills arriving afterwards, partly as a function of earlier development. The graphic representation is designed to illustrate not only the process of development and how the staged nature of human growth occurs vis-à-vis vision, but it also provides a rough guide to approaching therapy.
Some have depicted vision as an emergent process, and this is well described here: A-model-of-Vision Paul Harris. Clearly human neural development, mirrored by behavioural evolution, would support this notion. Others have taken this quite a bit further, to where ‘vision is the center of the universe’, an extreme that I would not easily support even though this graphic is useful in showing vision as a globally integrative and evolving sensory process. PDF: vision-is-center_Lowery-Venn-diagram
Many have elaborated this visual representation of visual development as a pyramid, and I have long wanted to have a try at it. It is impossible to include all elements in one graphic, and so it is necessarily a work in progress.
Keep watching as I will be posting more information about the upcoming book, as well as more on the Pyramid.
PDF: The Visual Developmental ‘Pyramid’
PS – As this graphic is likely to change from time to time, I will endeavour to keep this post updated as the main source of the latest version.
Of course, any deficits or developmental delays in mechanical and/or neurological will present in early coordination / poor adaptation of the eyes causing stress and fatigue eventually triggering attempts to correct deficits and if that fails “adaptation exhaustion” will foster monocular adaptations ignoring one or other eye neurologically or actually physically becoming reliant on dominance of one or other eye presenting in an eye-turn of the so called, lazy eye when coordination fails.
In adults often an occupational visual health risk for display screen user operators suffering vision stress, binocular eye-strain sustaining convergence for prolonged periods on sub-optimally colour contrast calibrated screen interface in poorly or over brightly artificially lit environments.
Screen Fatigue or worse Computer Vision Syndrome, leading to myopic progression and asthenopia disease is only partly mitigated by 2018 WCAG 2.1 minimum Colour Contrast Validation accepting ISO 45001 “Work Exposure Limits” yet to be applied to DSE operators who have yet to benefit from “induction training” enabling them to make personal custom “Reasonable Adjustments” or “Accommodations” (2010 Equality Act) to prevent or mitigate vision stress debilitating convergence and accommodation after one to four hours on-screen without sufficient visual breaks or a “Right to Disconnect” outside of working hours.
We’ll agree to disagree on the extent of risk w/screen time. I tend to steer towards mitigation and facilitation, in which case people can operate for as long as they need for work purposes. Obviously, nutrition, sleep, exercise and ‘green before screen’ are all relevant and should be emphasized. Stress and inadequate lighting continue to be a problem in industrial settings, and yes, these can contribute to myopic progression given current evidence. Thanks for the comment. Dr. B