Abstract WP449: Right Hemisphere Dysfunction is more Accurately Detected by Prosody Impairment than by Hemispatial Neglect

Abstract

Introduction It is well known that right hemisphere ischemic stroke often results in hemispatial neglect. Recent studies have also shown that right hemisphere stroke may cause impairment in processing emotional prosody (tone of voice) as well. We tested the hypothesis that stroke patients are more accurately distinguished from neurologically intact controls by tests of emotional prosody comprehension than by tests of hemispatial neglect. Methods We tested a series of 29 patients (mean age - 55 years old and mean education - 14 years)within 48 hours of onset of first right hemisphere ischemic stroke and 23 hospitalized age- and education- matched controls with MRI, a prosody comprehension battery and a battery of hemispatial neglect tests (line cancellation, copying a scene, gap detection, line bisection) . Emotion categorization tasks assessed recognition of 6 emotion categories (happy, sad, angry, surprise, disinterest, neutral) from prosodic cues in 2 conditions with varying verbal demands (neutral sentences and monosyllables). We used Receiver Operating Characteristic curves to identify the scores that most accurately classified stroke patients versus controls, using summary scores for Prosody and Neglect based on all of subtests for each. Results The Prosody Score was more effective than the Neglect Score in distinguishing stroke patients from controls, as measured by a Receiver Operating Characteristic (AUC for Prosody Score = 0.86). An overall error rate of > 27% on the prosody comprehension battery had a sensitivity of 89.74% and specificity of 68.18% (correctly classifying 82.0% of participants as patients vs controls). In contrast, the AUC for Neglect Summary Score was 0.55. At most, the Neglect Score could classify 55.8% of patients vs. controls. Of 25 patients who made >27% errors on Prosody Comprehension, 22 (88%) made 0% errors on the Neglect battery. Conclusion Prosody impairment may be a better indicator of right cortical dysfunction than hemispatial neglect in acute stroke and may therefore be a better measure of effectiveness of interventions to salvage cortical function, such as reperfusion therapies.