Department of Neurology, Washington University, Saint Louis, Missouri, United States of America.
Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.
PLoS One. 2019 Mar 7;14(3):e0213010. doi: 10.1371/journal.pone.0213010. eCollection 2019.
Working memory performance is a key indicator of cognitive and developmental status. While recent evidence indicates that stabilizing neural gain supports the stabilization of working memory during adolescence, the computational mechanisms linking neural stabilization to behavior are poorly understood. We develop a mechanistic account of behavior during the memory-guided saccade task based on a stochastic accumulator framework. Results indicate that a specific balance of independent gain signals affecting working memory representations and oculomotor response thresholds can account for a peculiar U-shaped feature of the speed-accuracy relationship. Additionally, aspects of behavioral variability and mean behavioral performance, as well as subtle shifts in the shape of the speed-accuracy relationship across development, can be accounted for by the stabilization of these two sources of variability. Thus, the stabilization of neural variability can, in part, account for developmental improvements in behavioral variability as well as some improvement in mean behavioral performance.
工作记忆表现是认知和发展状况的关键指标。虽然最近的证据表明,稳定的神经增益支持青少年时期工作记忆的稳定,但将神经稳定与行为联系起来的计算机制仍知之甚少。我们基于随机累积器框架,提出了一种记忆引导眼跳任务期间行为的机制解释。结果表明,影响工作记忆表示和眼动反应阈值的独立增益信号的特定平衡,可以解释速度准确性关系中特有的 U 型特征。此外,行为变异性和平均行为表现的各个方面,以及随着发展而在速度准确性关系形状上的微妙变化,都可以通过这两个变异性来源的稳定来解释。因此,神经变异性的稳定可以在一定程度上解释行为变异性的发展改善,以及平均行为表现的一些改善。