ABSTRACT
INTRODUCTION: Idioms are commonly used in everyday language to convey emotions figuratively. The ability to comprehend and use idioms that incorporate emotional elements is crucial for effective communication in daily life, particularly among people with aphasia (PwA). Despite the interest in understanding the process of emotion idiom comprehension in PwA, limited information is available in the literature. Therefore, this study aimed to investigate the process of emotion idiom comprehension in people with Wernice's aphasia (PwWA) and compare it with that of neurotypical individuals. METHODS: Sixty idioms were selected based on their syntactic and semantic features, and participants evaluated their imageability. Sixteen idioms were chosen for the study and two types of tasks were prepared: written idiom-picture matching and written idiom-written text matching. These tasks were administered to two groups: 11 PwWA and 11 neurotypical individuals. The results were analysed in terms of task performance, response type, syntactic and semantic features, and emotional content. RESULTS: The emotion idiom comprehension scores of PwWA group were significantly lower than those of the neurotypical participants. PwWA had greater difficulty with the written idiom-picture matching task and tended to rely on the literal meanings of the idioms. There were differences in the semantic features between the two groups. Among the emotional idioms, PwWA showed significant differences in the types of emotions they were able to comprehend. CONCLUSIONS: The findings of this study suggest that regardless of the syntactic content of idioms, PwWA's ability to comprehend emotion idioms is impaired, and they tend to interpret them more literally. This study provides a useful method for assessing emotional idiom comprehension in PwA.
ABSTRACT
Previous neuropsychological data have equivocal suggestions concerning hemispheric involvement during idiom comprehension. The possible contribution of idioms transparency to the lateralization of figurative language comprehension has not been investigated using an interference technique. To analyse the cortical lateralization of idiom transparency processing, we employed inhibitory repetitive transcranial magnetic stimulation (rTMS) to the left and right dorsolateral prefrontal cortex (DLPFC) during the processing of opaque idioms, transparent idioms, and non-idiomatic literal phrases. Based on the Coarse Semantic Coding theory, we predicted a greater right hemisphere involvement when processing opaque than transparent idioms. Eighteen young healthy participants underwent rTMS pulses at 1 Hz frequency, 110% of motor threshold intensity for 15 min (900 pulses) in two sessions at one-week intervals. In a semantic decision task, participants judged the relatedness of an idiom and a target word. The target word was figuratively or literally related to the idiom, or unrelated. The study also included non-idiomatic sentences. We found that left DLPFC functions are more critical for comprehension of opaque rather than transparent idioms when referring to the figurative associations of the idioms. Opaque idioms, in the context of their figurative meaning, rely more heavily on left hemisphere resources. This finding suggests that opaque idioms are seemingly processed as one unit. Taken together, we believe that the transparency of idiomatic expressions may play an important role in modulating hemispheric functions involved in figurative language processing.
