Recognition of auditory sequences by aphasic, right-hemisphere-damages and non-brain-damaged subjects

Non-brain-damaged, nonaphasic right-hemisphere-damaged and aphasic left-hemisphere-damaged subjects performed in a task in which they reported whether pairs of sequences of one, two or four pure tones were the "same" or "different" in pitch. Brain-damaged subjects performed less well than non-brain-damaged subjects. Subjects with right hemisphere damage performed progressively less well as the number of tones within tone sequences increased, but non-brain-damaged and aphasic subjects more accurately reported four-tone than two-tone sequences. The results suggested that the deficits in temporal sequencing by aphasic subjects previously reported in the literature do not result from output disorders, and that subjects with hemisphere lesions exhibit deficits that are consistent with deficits in the ability to process melodic materials.