Psychology 2043A/B Chapter Notes - Chapter 10: Visual Acuity, Optic Nerve, Visual Impairment

• School: Western University
• Department: Psychology
• Course: Psychology 2043A/B
• Professor: Ingrid L.Stefanovic

Document Summary

Unlike other disabilities, visual impairment has both legal and educational definitions. Based on visual acuity and field of vision. Visual acuity - abilities to clearly distinguish forms or discriminate among details. Most often measured using the snellen eye chart. 20/20 vision - does not mean perfect vision. At a distance of 20 feet, the eye can see what a normally seeing eye sees at that distance. As the bottom number increases, visual acuity decreases. Person who has 20/200 vision or less in the better eye with the use of a corrective lens is considered legally blind by the federal gov"t. Person with visual acuity no better than 20/70 in the better eye after correction is considered partially sighted. Person may also be considered legally blind if his/her field of vision is extremely restricted. If restricted to 20 degrees or less = legally blind. Definition under idea emphasizes the relationship between vision and learning (pg.