Tomasi Dardo, Volkow Nora
National Institutes of Health.
National Institute on Drug Abuse National Institutes of Health.
Res Sq. 2025 May 13:rs.3.rs-6495742. doi: 10.21203/rs.3.rs-6495742/v1.
Interhemispheric asymmetry is a core feature of human brain organization, yet its functional relevance across cognitive domains remains incompletely understood. Using data from 989 participants in the Human Connectome Project, we examined patterns of functional asymmetry and their relationship to task performance across seven domains-motor, language, social cognition, relational processing, working memory, gambling, and emotion. An fMRI-derived asymmetry index was computed across 17 task contrasts and mapped onto the cortical surface. Both fMRI signal amplitude and asymmetry were positively associated with task accuracy across multiple networks and cognitive domains. These associations were strongest in language, frontoparietal, and dorsal attention networks during high-demand tasks, such as story comprehension, relational processing, and working memory. Partial least squares regression revealed that while amplitude was the more robust predictor of task accuracy, asymmetry contributed unique, complementary variance. These findings suggest that greater neural activation and stronger hemispheric differentiation jointly support better cognitive performance. Together, our results underscore the behavioral relevance of both fMRI signal amplitude and lateralization, offering new insights into the functional architecture and efficiency of the human brain.
半球间不对称是人类大脑组织的一个核心特征，然而其在各个认知领域的功能相关性仍未被完全理解。利用人类连接组计划中989名参与者的数据，我们研究了功能不对称模式及其与七个领域（运动、语言、社会认知、关系处理、工作记忆、赌博和情感）任务表现的关系。通过17种任务对比计算出基于功能磁共振成像的不对称指数，并将其映射到皮质表面。功能磁共振成像信号幅度和不对称性在多个网络和认知领域都与任务准确性呈正相关。在诸如故事理解、关系处理和工作记忆等高要求任务中，这些关联在语言、额顶叶和背侧注意网络中最为强烈。偏最小二乘回归显示，虽然幅度是任务准确性更强有力的预测指标，但不对称性也贡献了独特的、互补的方差。这些发现表明，更强的神经激活和更强的半球分化共同支持更好的认知表现。总之，我们的结果强调了功能磁共振成像信号幅度和偏侧化在行为上的相关性，为人类大脑的功能结构和效率提供了新的见解。
