Autotopagnosia

From Psy3241

Autotopagnosia is a neuropsychological syndrome characterized by the inability to name or locate parts of one's own (or, in some cases, another person's) body. This peripersonal space disorder is usually associated with generalized brain damage or lesions of the left parietal lobe.

The symptoms of autotopagnosia are widely varied. For example, some individuals with the disorder can correctly identify parts of inanimate objects or animals, but are unable to locate the parts of a human body, whether it is their own or someone else’s. Others can effectively identify isolated parts of a human body (for instance, a picture of an arm by itself), but are unable to identify body parts when they are presented as a whole human body. Because of the symptoms are so highly varied across affected individuals, autotopagnosia (along with most other neuropsychological disorders) likely has more than one underlying cause.

There are several main hypotheses describing the underlying cognitive deficits that might cause the disorder:

• It is a language problem. More specifically, it is a category-specific comprehension deficit. Because the disorder is often associated with a lesion in the posterior left hemisphere (the part of the brain responsible for language), difficulty in describing body parts (or describing things in general) is likely to occur in affected individuals.
• It is a visuospatial problem. If the lesion causing the disorder is located in the (visuospatial) parietal lobe, the affected individual would probably have difficulty pointing to parts of an object.
• It is a body image problem. Since body image is mediated by systems in the left parietal lobe, a disruption of this region might lead to the inability to point to human body parts.

Reference:

Ogden, J. A. (2005). Fractured Minds: A Case Study Approach to Neuropsychology. Second Edition. New York: Oxford University Press.