[Arithmetic intuition in an acalculic].

At age 54, a patient presented Wernicke's aphasia and a Gerstmann's syndrome with right hemianopia. CT scan showed a low density area in the left hemisphere in the posterior parts of T1 and T2 and parts of T3, extending into the gyrus angularis and gyrus supramarginalis. Wernicke's aphasia, digital agnosia and confusion between left and right hand improved six months later, but agraphia remained total and calculation disorders, both for mental and written calculation, were still very severe. Operation processes were retained. A dramatic improvement of performances could be obtained with written multiple choice questions.