BACKGROUND Multiple sclerosis (MS) affects over 2.5 million individuals worldwide, yet much of the disease course is unknown. Hemispheric vulnerability in MS may elucidate part of this process but has not yet been studied. The current study assessed neuropsychological functioning as it relates to hemispheric vulnerability in MS. METHODS Verbal IQ, as measured by verbal comprehension index (VCI), nonverbal IQ, as measured by perceptual reasoning index (PRI) and memory acquisition were compared in right-handed (dextral) and non-right-handed (non-dextral) persons with MS (PwMS). RESULTS Linear mixed-effects modeling indicated a significant main effect of handedness, F(1, 195.35) = 3.95, p = .048, for a composite measure of VCI, PRI, and memory acquisition, with better performance for dextral PwMS. In examining differences for specific neuropsychological measures, the largest effect size between dextral and non-dextral participants was seen in PRI (d = 0.643), F(1,341) = 12.163, p = .001. No significant interaction effect between handedness and IQ was found, F(3, 525.60) = 0.75, p = .523. CONCLUSIONS Dextral PwMS perform better than non-dextral PwMS when assessing neuropsychological performance for memory and IQ combined. Results are suggestive of increased vulnerability in the left brain to the pathological process of MS.

中文翻译：

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多发性硬化症中的惯用手和认知：大脑半球脆弱性的潜在适应症。

背景技术多发性硬化症(MS) 影响全世界超过250 万人，但大部分疾病过程是未知的。MS 中的半球脆弱性可能阐明了这一过程的一部分，但尚未进行研究。目前的研究评估了神经心理功能，因为它与 MS 的半球脆弱性有关。方法 通过语言理解指数 (VCI) 测量的语言智商、通过知觉推理指数 (PRI) 测量的非语言智商和记忆获取在右手（右旋）和非右手（非右旋）的人中进行比较与 MS (PwMS)。结果 线性混合效应模型表明，对于 VCI、PRI 和记忆采集的综合测量，左手习惯具有显着的主效应，F(1, 195.35) = 3.95, p = .048，右旋 PwMS 具有更好的性能。在检查特定神经心理学测量的差异时，在 PRI (d = 0.643)、F(1,341) = 12.163、p = .001 中观察到右旋参与者和非右旋参与者之间的最大效应量。未发现惯用手和智商之间存在显着的交互作用，F(3, 525.60) = 0.75, p = .523。结论 右旋 PwMS 在评估记忆和智商的神经心理表现时比非右旋 PwMS 表现更好。结果表明左脑对 MS 病理过程的易感性增加。结论 右旋 PwMS 在评估记忆和智商的神经心理表现时比非右旋 PwMS 表现更好。结果表明左脑对 MS 病理过程的易感性增加。结论 右旋 PwMS 在评估记忆和智商的神经心理表现时比非右旋 PwMS 表现更好。结果表明左脑对 MS 病理过程的易感性增加。