Aprosodia Following Focal Brain Damage: What's and What's Left?

Purpose: Hemispheric specialization for the comprehension and expression of lin-guistic and emotional prosody is typically attributed to the right hemisphere. This study used techniques adapted from meta-analysis to critically examine the strength of existing evidence for hemispheric lateralization of prosody following brain damage. Method: Twenty-one databases were searched for articles published from 1970 to 2020 addressing differences in prosody performance between groups defined by right hemisphere damage and left hemisphere damage. Hedges's g effect sizes were calculated for all possible prosody comparisons. Primary analyses summarize effects for four types: linguistic production, linguistic comprehension, emotion comprehension, and emotion production. Within each primary analysis, Hedges's g values were averaged across comparisons (usually from a single article) based on the same sample of individuals. Secondary analyses explore more specific classifications of comparisons. Results: Out of the 113 articles investigating comprehension and production of emotional and linguistic prosody, 62 were deemed appropriate for data extrac-tion, but only 21 met inclusion criteria, passed quality reviews, and provided sufficient information for analysis. Evidence from this review illustrates the hetero-geneity of research methods and results from studies that have investigated aprosodia. This review provides inconsistent support for selective contribution of the two cerebral hemispheres to prosody comprehension and production; however, the strongest finding suggests that right hemisphere lesions disrupt emotional prosody comprehension more than left hemisphere lesions. Conclusion: This review highlights the impoverished nature of the existing liter-ature; offers suggestions for future research; and highlights relevant clinical implications for the prognostication, evaluation, and treatment of aprosodia. Supplemental Material: https://doi.org/10.23641/asha.20334987