Reading and listening comprehension in Cantonese-speaking people with right hemisphere versus left hemisphere brain damage

The problem in language comprehension in people with right hemisphere damage (RHD) is more equivocal than people with left hemisphere damage. This study explores the reading and listening comprehension of Cantonese-speaking individuals with RHD, left hemisphere damage, and neurotypical healthy controls using the Cantonese Computerized Revised Token Test (CRTT-Cantonese) adapted from the English CRTT. Eighteen native Cantonese-speaking individuals with RHD, 32 individuals with left hemisphere damage and aphasia (PWA), and 42 healthy controls participated in this study. All the participants completed the Cantonese Aphasia Battery, Hong Kong Oxford Cognitive Screen, the listening comprehension version of CRTT-Cantonese (CRTT-L-Cantonese), and the reading comprehension version of CRTT-Cantonese (CRTT-R-_WF-Cantonese) across different sessions. Linear mixed-effect analysis revealed significant differences among the groups in CRTT-Cantonese tests. However, there were no significant difference between CRTT-L-Cantonese and CRTT-R-_WF-Cantonese within the PWA, RHD and healthy control groups. Tukey post-hoc pairwise comparisons showed that PWA scored significantly lower than RHD and healthy control groups (p < 0.0001) in both CRTT-L-Cantonese and CRTT-R-_WF-Cantonese, and the RHD group scored significantly lower than healthy control group only on the CRTT-R-_WF-Cantonese. The results demonstrate that the CRTT-L-Cantonese and CRTT-R-_WF-Cantonese differentiate language comprehension abilities among PWA, RHD and healthy control groups. Although the current findings did not show any diversion between reading and listening comprehension in RHD group, this group showed poorer performance in reading comprehension when compared to healthy controls. The latter findings may support the view that the right hemisphere contributes to reading comprehension in Chinese.