Recognition of affective prosody in autism spectrum conditions: A systematic review and meta-analysis

Affective prosody recognition is an important area of research in autism spectrum conditions where difficulties in social cognition have been frequently observed. To probe into the mixed results reported in the literature, we conducted a systematic review with meta-analysis and examined potential factors that could explain the inconsistent results. Our literature search included six electronic databases for studies that compared the affective prosody recognition performance in individuals with autism spectrum condition with typically developing participants, which yielded 23 papers eligible for quantitative synthesis. Using a random-effects model, we obtained a moderate-to-large pooled effect (Hedges’ g = −0.63) for the overall affective prosody recognition performance of autism spectrum condition participants, which, however, reduced substantially (to −0.26) and became non-significant after the correction for publication bias. The number of answer codes was found to be a significant moderator for the effect estimate, whereas the number of speakers was not. Moreover, the magnitude of the pooled effect estimate varied across emotions. The findings suggested moderate differences in affective prosody recognition ability between autism spectrum condition and typically developing individuals, which reduced to marginal difficulties for autism spectrum condition when the impact of publication bias was taken into account. Diversity in the number of answer codes could have differential effects on affective prosody recognition performance in autism spectrum condition, which varied across emotions. The present review and meta-analysis demonstrated the insufficiency of research on affective prosody recognition in autism spectrum condition, highlighting a need for further exploration of the contributors and underlying mechanisms for specific affective prosody recognition difficulties. Lay abstract Differences in understanding others’ emotions and attitudes through features in speech (e.g. intonation) have been observed in individuals with autism spectrum conditions, which contribute greatly to their social communication challenges. However, some studies reported that individuals with autism spectrum condition performed comparably to typically developing individuals on affective prosody recognition. Here, we provide a comprehensive review with statistical analysis of 23 existing studies on this topic to examine potential factors that could explain the discrepancies. Compared with typically developing individuals, autism spectrum condition participants generally appeared to encounter more difficulties in affective prosody recognition. But this finding was likely due to the tendency of the existing research to overly focus on deficits in autism. The affective prosody recognition performance in individuals with autism spectrum condition was closely related to the number of answer options offered to them. Moreover, the degree of difficulty in affective prosody recognition encountered by individuals with autism spectrum condition varied across emotions. The findings of this systematic review highlighted the need for further research on affective prosody recognition in autism (e.g. studies that include tonal language speakers and autism spectrum condition individuals with lower cognitive or verbal abilities).