Blindness

Structural Brain Changes Due to Blindness

Nicole Richardson - Baker College

There are half a million individuals that are blind in the United States (Breedlove & Watson, 2013). According to the American Foundation for the Blind (AFB) (n.d.), blindness is "... A wide array of conditions ranging from a limited ability to see objects with special aids to the absence of light perception. Most people who are blind have some light perception." (p. 1) "Almost all blindness in the United States is the result of eye disease. Less than 3 percent is the result of injuries." (AFB, n.d., p. 1)

Knowing these basic facts about blindness is only part of caring for an individual who has a visual impairment. Another key part is understanding what changes occur in the brain as a result of blindness.



(Science Daily, 2009.)

According to the Science Daily, (2009) "Now scientists from the UCLA Department of Neurology have confirmed that blindness causes structural changes in the brain, indicating that the brain may reorganize itself functionally in order to adapt to a loss in sensory input." (p. 1) However, this does not mean that those who are blind have a keener senses (AFB, n.d.). According to the AFB (n.d.) "People who are blind or visually impaired are not endowed with a sharper sense of touch, hearing, taste, or smell. To compensate for their loss of vision, many learn to listen more carefully, or remember without taking notes, or increase directional acumen to compensate for their lack of functional vision." (p. 1) Therefore, we should not assume that those who are visually impaired are incapable of living productive lives, as they are able to function as those who have their sight, just through adapted senses.


In addition to these adaptations with their senses occurring "...researchers found significant enlargement in areas of the brain not responsible for vision. For example, the frontal lobes, which are involved with, among other things, working memory, were found to be abnormally enlarged, perhaps offering an anatomical foundation for some of blind individuals' enhanced skills." (Science Daily, 2009, p. 1) Just as with those who are not blind, plasticity is also occurring in the blind, meaning there is changing occurring and new neurons that are being produced in the brain. Both visually impaired and those who do not have an impairment utilize the visual cortex and the occipital-temporal cortex areas. The differences seen in these brain areas are in relation to processing information (Phillips, 2002). "Sighted people often encode visual information for this purpose, but blind people would encode touch information instead." (Phillips, 2002, p. 1)

(brainu.org)

In addition to this information the following link will provide a very informative and detailed video on visual impairment:

http://www.bloomberg.com/news/videos/b/358f1134-9560-4888-940e-1a3a987a3417

References

American Foundation for the Blind (n.d.) Learning about Blindness. Retrieved from: http://www.afb.org/info/living-with-vision-loss/for-job-seekers/for-employers/visual-impairment-and-your-current-workforce/learning-about-blindness/12345

Breedlove, S.M., & Watson, N.V. (2013). Biological Psychology: An Introduction to Behavioral, Cognitive, and Clinical Neuroscience (7th Ed.). Sunderland, MA: Sinauer Associates, Inc.


Phillips, M.L. (2002, May 20). Visual Cortex Activity in the Blind. Retrieved from: https://faculty.washington.edu/chudler/brail.html

Science Daily, (2009, November 19). Science causes structural brain changes, implying brain can re-organize itself to adapt. Retrieved from: http://www.sciencedaily.com/releases/2009/11/091118143259.htm