ON CROSSED APRAXIA - DESCRIPTION OF A RIGHT-HANDED APRAXIC PATIENT WITH RIGHT SUPPLEMENTARY MOTOR AREA DAMAGE

GP, a right-handed woman, without evidence of familial left-handedness , showed clearcut bilateral ideo-motor apraxia and oro-facial apraxia after a vascular lesion of the right hemisphere, encroaching upon the fronto-mesial region. She scored normally in most other cognitive test s, including language, but showed signs of callosal disconnection, lef t anarchic hand and mild unilateral spatial neglect. This cognitive pr ofile points to the possibility of praxis being localized to the right hemisphere in this right-handed patient. We argue in favour of indivi dual variability of praxis dominance, and maintain that this dominance might be completely right-sided in some subjects. Moreover the anatom ical locus of GP's lesion points to the possible role that the frontal lobes (and more specifically the Supplementary Motor Area) play in th e genesis of apraxia.