An Examination of Visual Agnosia

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An Examination of Visual Agnosia

Imagine a researcher requesting you to copy a picture. It's a simple task. You move your instrument of illustration across a sheet of blank paper with ease, glancing from the given picture to your own sketch in progress. When you are finished you observe a satisfactory replica and feel a sense of accomplishment and proficiency with the similarity you have achieved between picture and sketch. Then the researcher queries whether you can tell him what you have drawn. You search the interconnected lines, the edges, and the shapes of your sketch but cannot answer what the picture represents. Finally, an explanation is given. You have just drawn a house- a simple triangle resting on top of a square. Your sense of accomplishment is quickly replaced with a feeling of despair.

Visual agnosia is a neurological disorder characterized by the inability to recognize familiar objects (Farah, 1990). Object recognition is the ability to place an object in a category of meaning. Most cases of visual agnosia are brought about through cerebral vascular accidents or traumatic brain injury typically inhibiting sufficient amounts of oxygen from reaching vital body tissues (Zoltan, 1996). There are a vast array of impaired abilities and deficits associated with individuals diagnosed with visual agnosia. These impairments vary considerably from individual to individual (Farah, 1990). Some patients cannot recognize pictures of things such as trees and birds, despite being able to describe such objects or recognize them through other senses such as sound and touch. Other patients demonstrate an inability to recognize faces of friends and family members (Goodale, 1995). The functional impairments experienced as a r...

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