Deficits in Visuospatial/Visuoconstructional Skills and Motor Praxis
Visuospatial and visuoperceptual skills play a role in every day functioning; however, they are typically automatic. We process information visually and make identifications and analyze complex visual stimuli and are largely unaware of the visuoperceptual process involved or complexities of the stimuli that were analyzed. As an example, assume that you have purchased a new car and now suddenly that make and model seems to be everywhere. You suddenly notice the different colors in which the car comes, the different trim packages, and optional equipment (i.e., roof racks, spoiler, etc.). Soon you find yourself distinguishing among similar year models based on detail changes such as tail light configuration or color-matching door hardware. You can also identify this car from multiple angles (front, side, rear, corner, etc.) These complex stimuli are typically automatically perceived, poorly verbally labeled, yet precisely and accurately analyzed and identified. The centers in the brain that process such information are ever vigilant to visual and visuospatial stimuli and organized to simultaneously and sequentially take that information and transform it into usable, salient information or associated knowledge. All this occurs in a split second and typically below our level of awareness. While this process can certainly be consciously controlled, typically in novel learning or acquisition stages, our nature is to use repetition, familiarity or repeated recurrence to allow for more automatic processing and save the conscious and effortful processing capacities for the novel or necessary tasks at hand.
If this process is impaired, many types of deficits occur, from failure to process basic elements in the visual stimuli (i.e., color, lines, orientation) to more complex and integrative features such as object identification, faces or familiar scenes. These deficits can include phenomena such as visual neglect and hemi-inattention or more dramatic visual agnosias or prosopagnosia. This impairment may include what is referred to as disconnection syndromes in which centers of basic visual sensory functions are dissociated or disconnected from association cortex areas that allow for synthesis or analysis necessary to recognize the sensory stimuli as a specific object.
KeywordsVisual Field Primary Visual Cortex Fusiform Face Area Cortical Blindness Parietal Lesion
References and Suggested Further Reading
- Benton, A. L., Hannay, H. J., & Varney, N. R. (1975). Visual perception of line direction in patients with unilateral brain disease. Neurology, 25, 907–910. Reprinted in L. Costa & O. Spreen (Eds.) (1985). Studies in neuropsychology. Selected papers of Author Benton. New York: Oxford University Press.PubMedCrossRefGoogle Scholar
- Heilman, K., & Valenstein, E. (2003). Clinical neuropsychology. New York: Oxford University Press.Google Scholar
- Hooper, H. E. (1983). Hooper visual organization test manual. Los Angeles: Western Psychological Services.Google Scholar
- Kolb, B., & Whishaw, I. (2009). Fundamentals of human neuropsychology (5th ed.). New York: W.H. Freeman.Google Scholar
- Lezak, M., Howieson, D., & Loring, D. (2004). Neuropsychological Assessment, (4th ed.) Oxford, New York.Google Scholar
- Loring, D. W., & Meador, K. J. (2003). The Medical College of Georgia (MCG) Complex Figures: Four forms for follow-up. In J. Knight & E. Kaplan (Eds.), Rey-Osterrieth handbook. Odessa: Psychological Assessment Resources.Google Scholar
- Taylor, L. B. (1979). Psychological assessment of neurosurgical patients. In T. Rasmussen & R. Marino (Eds.), Functional neurosurgery. New York: Raven.Google Scholar