Abstract Twenty-four aphasic subjects with left hemisphere brain damage, fifteen subjects with right hemisphere brain damage and twenty control subjects with no brain damage participated in visual temporal and auditory spatial sequencing tasks. In the visual temporal task, four colored lights were flashed in various sequences, and subjects reported the order of the lights by operating colored pushbuttons. In the auditory spatial task, bursts of noise were delivered in various sequences to four speakers placed in an arc around the subject, and subjects reported the order of the sounds by operating push-buttons under each of the speakers. Both groups of brain damaged subjects performed less well on both tasks than the group of normal subjects, and both groups of brain damaged subjects performed less well on the auditory temporal task than the visual spatial task. Further investigations to specify the functions served by the two hemispheres are proposed.