autotopagnosia

n. Inability to name, recognize, or point on command to parts of the body. Patients have significant difficulty in localizing and naming body parts, not only of their body, but also of the examiner's body, a doll's, or a representation of the human body. A discrepancy between the ability to point to and name external objects and body parts is observed. Rarely, this defect is found without any other aphasic manifestation.

Patients seem to understand the name of the body part, but they fail in finding where specific body parts are located. Sometimes, they present an approximate answer: that is, they look for the eyes in the head, not in the trunk. Occasionally, they fail in finding the body part but can point to it correctly if it is named by another person.

Different hypotheses have been proponed to explain this syndrome: (1) there is a language defect restricted to the conceptualization of the body parts, (2) there is an impairment in the spatial representation of the body, (3) considering that sometimes patients also have difficulties in pointing to and naming parts of objects, it has been suggested that there is a global defect in the perceptual integration of elements in a whole.

Autotopagnosia is usually correlated with left hemisphere lesions, particularly posterior parietal damage, but has been also observed in cases of extensive bilateral lesions. Autotopagnosia is frequently associated with signs of the Gerstmann syndrome, or angular gyrus syndrome (acalculia, agraphia, disorders in right-left orientation, and finger agnosia)  

-AA