Metaphor comprehension in brain-damaged patients: Focus on deficits in right-hemisphere-damaged patients

Abstract

A metaphor comprehension task was administered to 15 healthy adults (control group), 15 right-hemisphere-damaged patients without communication disorders (RHDgroup), 15 right-hemisphere-damaged patients with communication disorders (RHD+ group), and 15 left-hemisphere-damaged aphasic patients (aphasic group). We selected 30 similes. All of them were of low familiarity, requiring effort to understand their meaning (e.g. "Roads are like blood vessels."). With each question, the examiner read aloud the metaphor sentence, and the respondent was asked to choose a written statement that best represented its meaning from among four choices. In addition, all the subjects were asked to perform a metaphor description task (they were asked to explain the meaning of the same metaphors) and the Token Test (TT). The results showed that the scores of the metaphor comprehension task and TT in the RHD- group were not significantly different from those in the control group. On the other hand, the RHD+ group exhibited significantly poorer scores, especially on the metaphor comprehension task, than those in the control group. In the aphasic group, the scores of the metaphor comprehension task and TT were significantly poorer than those in the control group. Scores of the metaphor comprehension task and the metaphor description task were significantly correlated. Metaphor comprehension deficits in right-hemisphere-damaged patients may need to be discussed taking their communication disorders into consideration.