Unilateral neglect and constructional apraxia in a right-handed artist with a left posterior lesion.

A rapidly growing tumor in the left posterior parietal lobe of a right-handed, 72 year old artist resulted in bilateral neglect and constructional apraxia that were greater on the right side of his painting than on the left. These changes indicate that a left posterior parietal lesion alters visuospatial perception and constructional ability on both sides of a painting with the contralateral hemispace more impaired than the ipsilateral hemispace. Primitivization of emotional expressions on human faces also occurred.