Qin Shaozheng, Cho Soohyun, Chen Tianwen, Rosenberg-Lee Miriam, Geary David C, Menon Vinod
Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California, USA.
1] Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California, USA. [2] Department of Psychology, Chung-Ang University, Seoul, South Korea.
Nat Neurosci. 2014 Sep;17(9):1263-9. doi: 10.1038/nn.3788. Epub 2014 Aug 17.
The importance of the hippocampal system for rapid learning and memory is well recognized, but its contributions to a cardinal feature of children's cognitive development-the transition from procedure-based to memory-based problem-solving strategies-are unknown. Here we show that the hippocampal system is pivotal to this strategic transition. Longitudinal functional magnetic resonance imaging (fMRI) in 7-9-year-old children revealed that the transition from use of counting to memory-based retrieval parallels increased hippocampal and decreased prefrontal-parietal engagement during arithmetic problem solving. Longitudinal improvements in retrieval-strategy use were predicted by increased hippocampal-neocortical functional connectivity. Beyond childhood, retrieval-strategy use continued to improve through adolescence into adulthood and was associated with decreased activation but more stable interproblem representations in the hippocampus. Our findings provide insights into the dynamic role of the hippocampus in the maturation of memory-based problem solving and establish a critical link between hippocampal-neocortical reorganization and children's cognitive development.
海马体系统对快速学习和记忆的重要性已得到充分认可，但其对儿童认知发展的一个基本特征——从基于程序的问题解决策略向基于记忆的问题解决策略的转变——的贡献尚不清楚。在此，我们表明海马体系统对这一策略转变至关重要。对7至9岁儿童进行的纵向功能磁共振成像（fMRI）显示，在解决算术问题时，从使用计数到基于记忆的检索的转变与海马体活动增加以及前额叶-顶叶活动减少同时出现。海马体-新皮质功能连接性增强预示着检索策略使用的纵向改善。在童年之后，检索策略的使用在青少年期直至成年期持续改善，并且与海马体中激活减少但问题间表征更稳定有关。我们的研究结果为海马体在基于记忆的问题解决成熟过程中的动态作用提供了见解，并在海马体-新皮质重组与儿童认知发展之间建立了关键联系。
