Deficits in spoken discourse comprehension are common after left hemisphere (LH) and right hemisphere (RH) stroke. Thus, it is important to identify factors that facilitate comprehension and enhance communication between stroke survivors and their care partners. Emotional prosody and facial expression cues can facilitate comprehension, but this may depend on an intact RH. To determine if such cues are facilitatory to LH and RH stroke survivors, we compared discourse comprehension between the groups across 3 conditions. We hypothesized that RH participants would not benefit as much from these cues as LH participants due to concomitant impairments in recognition of prosody and facial expression. We assessed 72 stroke survivors within 3 months of unilateral ischemic stroke, including 40 LH (15 female; aged 62±13 yrs) and 32 RH (17 female; aged 68±10 yrs), and 29 healthy controls (19 female; aged 72±15 yrs). Participants listened to a series of recorded spoken descriptions of scenarios and selected 1 picture from 4 to match each scenario. Targets and foils were balanced across spatial positions. Each description was presented in 3 conditions: read with neutral prosody (Trial 1), read with emotional prosody (Trial 2), and read with emotional prosody + facial expressions (Trial 3, audio + video). If 100% accuracy was achieved on a trial, the next trial was not presented. We used a Kruskal-Wallace test and paired samples t -tests for analyses and corrected for multiple comparisons. Accuracy differed significantly between groups on Trial 1, H (2) = 26.68, p < .001. Controls achieved higher accuracy than LH ( p < .01) and RH participants ( p < .01). LH and RH participants did not differ, p = .51. LH participants achieved significant gains in accuracy from Trial 1 to 2 ( t (32) = 4.16, p = .001) and from Trial 1 to 3 ( t (32) = 5.49, p < .001), but not from Trial 2 to 3 ( t (32) = 1.79, p = .08). RH participants did not achieve significant gains in accuracy from Trial 1 to 2 ( t (23) = 1.59, p = .13), Trial 2 to 3 ( t (23) = 0, p = 1.0), or Trial 1 to 3 ( t (23) = 1.21, p = .24). To conclude, emotional prosody and facial expressions significantly improved discourse comprehension for LH but not for RH stroke survivors. Different/additional strategies to improve discourse comprehension after RH stroke are needed.
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