Vision Disorder of Focus

Vision Overview

A person's ability to see is determined by a number of organs in the human body. First, the receptor organ (the eye itself) receives visual stimuli in the form of light reflected off of an object. The eye itself has a number of muscles used to focus on objects around a person through expansion and contraction. The light energy absorbed by the eye is transformed in to electrical energy that can be utilized by the brain in a process called transduction, (Goldstein, 2010). This energy then travels a path through the neurons in the brain to be recognized. The brain is the processing organ, but the specific areas that deal with visual information are the occipital lobes and the frontal lobes (Goldstein, 2010). Here, the electrical signals are processed and able to be perceived by the person.

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, 2010)


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.