constructional apraxia /kənstruk″shənəl/ [L, construere, to build] , a form of apraxia characterized by the inability to copy drawings or to manipulate objects to form patterns or designs. It is caused by a right hemisphere lesion. The deficit is tested by asking the patient to copy two-dimensional geometric patterns, such as circles, squares, diamonds, and hexagons, and to copy three-dimensional structures constructed of 1-inch building blocks.
