Verbal memory and semantic clustering in right brain-damaged patients.

Twenty-four right brain-damaged patients without ostensive signs of intellectual impairment or disturbances of verbal comprehension, and 20 normal control subjects were given two lists of words, one (the Rey's Auditory) in which 15 words were semantically unrelated and a second in which 15 two-syllable words belonged to one of three categories. The results demonstrated no difference between the two subject groups, either in the immediate or the delayed recall sections of the Rey's test. The immediate recall section of the semantic verbal memory task, on the contrary, showed significantly poor performance by the right brain-damaged patients. These results suggest an impairment of semantic clustering processes after right hemisphere damage.