Vision Disorder of Focus
A view showing the distribution of processed information in the brain. Vision information is passed along for more information to be determined, such as the location of the visual stimuli and a definition of the visual stimuli.
A view of the eyes and brains, showing the neuropathways of vision. More specialized structures are presented that all play a role in processing visual stimuli.
This image shows the very basic neuropathway that electrical signals travel due to visual stimuli. Light energy enters through the eye, is changed into electrical energy and sent along the optic nerve into the visual cortex.
Vision in Presbyopia
Presbyopia is a progressive condition affecting individuals later in life (typically in their 40s) which causes individuals lose the ability to focus on close objects, (Park & Kim, 2014). Far away objects, such as street signs when driving or images on posters, are still as clear as ever, but small print in books and on computer screens is not as easy to view as previously. Since it is a progressive, gradual condition, one may notice the onset slowly if they did not have vision problems before. Corrective lenses can help this condition.
Perception and Gestalt Principles
When processing visual information, our brains must make sense of what we are seeing as much as seeing the stimuli itself. If we only saw green all over the ground and blue in the sky, operating within our environment would be very confusing, if not impossible. Gestalt postulated principles that deal with how we organize images we see:
· Good continuation – How points connect from point “A” to point “B”
· Good Figure/Simplicity/Pragnanz – Patterns are viewed as simple as possible
· Similarity – The Grouping of similar things
· Proximity – Things arranged close together appear to be grouped
· Common Fate – Objects appear to be grouped together when moving in the same direction
· Common Region (Similar to Proximity) – Objects that are in the same space appear to be grouped together
· Uniform Connectedness – Items sharing similar characteristics (color, shape, etc.) are seen as a single unit
Goldstein, E. B. (2010). Sensation and Perception. Belmont: Wadsworth, Cengage Learning.
Park, J. H., & Kim, M. J. (2014). Surgical Treatment of Presbyopia. Journal of the Korean Medical Association, 520-524.