Transient inaccuracy in reaching caused by a posterior parietal lobe lesion

A transient disturbance of manual reaching in both hemispaces associated with a small contralateral posterior perietal lobe (area 7) lesion is described. This defect was increased when the patient tried to reach without viewing of the affected arm. Inaccurate reaching is a distinct syndrome from visuomotor or optic ataxia, and is interpreted as a failure in guiding the arm towards specific sites of the space.