Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, Montréal, QC, Canada.
Neuropsychologia. 2010 Nov;48(13):3802-14. doi: 10.1016/j.neuropsychologia.2010.09.003. Epub 2010 Sep 15.
This study investigated interhemispheric transfer in ten normal, four anterior-, and four totally-split-brain individuals, through measures of manual asynchrony and bimanually-recorded crossed-uncrossed difference (CUD). The CUD relied on the difference between crossed and uncrossed responses whereas the asynchrony measure relied on the reaction time difference between the two responding hands. Manipulations of sensory and attentional factors were assessed for both measures. We found a normal CUD (3.8 ms) along with an exacerbated and more variable asynchrony for partial split-brain individuals (40.8 ms) compared to normal individuals (CUD: 0.4 ms, asynchrony: 13.8 ms). In turn, the CUD of total split-brain individuals (20.4 ms) was larger than that of partial split-brain and normal individuals. Also, the asynchrony of total split-brain individuals (57.6 ms) was larger and more variable than that of normal individuals, and more variable than that of partial split-brain individuals. We interpret these results as behavioural evidence of independent mechanisms underlying the CUD and bimanual synchronization, as well as evidence of the joint involvement of both the anterior and the posterior portions of the corpus callosum in bimanual coordination.
本研究通过手动失谐和双手记录的交叉非交叉差异（CUD）测量，调查了 10 名正常、4 名前脑和 4 名全脑裂个体的大脑半球间转移。CUD 依赖于交叉和非交叉反应之间的差异，而失谐测量依赖于两个反应手之间的反应时间差异。两种测量方法都评估了感觉和注意力因素的操纵。与正常个体（CUD：0.4ms，失谐：13.8ms）相比，部分脑裂个体（CUD：3.8ms，失谐：40.8ms）的正常 CUD 较高，失谐也较大且更具变异性。相比之下，全脑裂个体的 CUD（20.4ms）大于部分脑裂和正常个体的 CUD。此外，全脑裂个体的失谐（57.6ms）较大且更具变异性，也比部分脑裂个体的失谐更具变异性。我们将这些结果解释为 CUD 和双手同步的独立机制的行为证据，以及胼胝体前后部分在双手协调中共同参与的证据。
