Neuropsychology and Functional Neuroimaging, Universitat Jaume I, Castelllón de La Plana, Spain.
Department of Psychology, University of York, York, UK.
Brain Struct Funct. 2024 Sep;229(7):1577-1590. doi: 10.1007/s00429-024-02822-3. Epub 2024 Jun 22.
The causal and statistical hypotheses diverge in determining whether the lateralization of language function in one cerebral hemisphere entails the lateralization of visuospatial function in the opposite hemisphere. Additionally, it remains unclear if the atypical segregation of these functions could influence cognitive performance. This study addresses these questions by examining the hemispheric lateralization of visuospatial attention during a line bisection judgement (landmark) task in three groups of healthy non-right-handed individuals with different language production segregations: left (typical), ambilateral (atypical), and right (atypical). Consistent with the causal hypothesis, results indicate that the groups with left and right language lateralization primarily utilize the opposite hemisphere for visuospatial attention. The ambilateral group, however, displays a pattern compatible with an independent segregation, supporting the statistical hypothesis. Behavioral analyses reveal that atypical lateralization of visuospatial attention (non-right) can lead to either better or worse performance during the landmark task, depending on the specific pattern. Bilateral organization is associated with reduced overall accuracy, whereas the left segregation results in improved performance during the most challenging trials. These findings suggest the existence of diverse pathways to lateralization, akin to either the causal or statistical hypothesis, which can result in cognitive advantages or disadvantages.
在确定大脑左半球的语言功能偏侧化是否意味着对侧半球的视空间功能偏侧化时，因果假说和统计假说存在分歧。此外，这些功能的非典型分离是否会影响认知表现仍不清楚。本研究通过检查三组不同语言产生分离的健康非右利手个体在直线二等分判断（地标）任务中的视空间注意的大脑半球偏侧化来解决这些问题：左（典型）、双侧（非典型）和右（非典型）。与因果假说一致，结果表明，具有左、右语言偏侧化的组主要利用对侧半球进行视空间注意。然而，双侧组显示出与独立分离一致的模式，支持统计假说。行为分析表明，视空间注意的非典型偏侧化（非右）可能导致地标任务的表现更好或更差，具体取决于特定模式。双侧组织与整体准确性降低相关，而左侧分离导致在最具挑战性的试验中表现提高。这些发现表明存在多种偏侧化途径，类似于因果或统计假说，这可能导致认知优势或劣势。
