Department of Neurology, University of California Irvine, USA.
Department of Anatomy & Neurobiology, University of California Irvine, USA.
Neuroimage. 2018 Jul 15;175:402-412. doi: 10.1016/j.neuroimage.2018.04.013. Epub 2018 Apr 9.
Adolescence is a complex period of concurrent mental and physical development that facilitates adult functioning at multiple levels. Despite the growing number of neuroimaging studies of cognitive development in adolescence focusing on regional activation patterns, there remains a paucity of information about the functional interactions across these participating regions that are critical for cognitive functioning, including memory. The current study used structural equation modeling (SEM) to determine how interactions among brain regions critical for memory change over the course of adolescence. We obtained functional MRI in 77 individuals aged 8-16 years old, divided into younger (ages 8-10) and older (ages > 11) cohorts, using an incidental encoding memory task to activate hippocampus formation and associated brain networks, as well as behavioral data on memory function. SEM was performed on the imaging data for four groups (younger girls, younger boys, older girls, and older boys) that were subsequently compared using a stacked model approach. Significant differences were seen between the models for these groups. Younger boys had a predominantly posterior distribution of connections originating in primary visual regions and terminating on multi-modal processing regions. In older boys, there was a relatively greater anterior connection distribution, with increased effective connectivity within association and multi-modal processing regions. Connection patterns in younger girls were similar to those of older boys, with a generally anterior-posterior distributed network among sensory, multi-modal, and limbic regions. In contrast, connections in older girls were widely distributed but relatively weaker. Memory performance increased with age, without a significant difference between the sexes. These findings suggest a progressive reorganization among brain regions, with a commensurate increase in efficiency of cognitive functioning, from younger to older individuals in both girls and boys, providing insight into the age- and gender-specific processes at play during this critical transition period.
青春期是一个身心同步发展的复杂时期，为成年后的多个层面的功能奠定基础。尽管越来越多的神经影像学研究关注青少年认知发展的区域激活模式，但对于这些参与区域之间对于认知功能至关重要的功能相互作用，包括记忆，仍缺乏信息。本研究使用结构方程模型（SEM）来确定在青春期过程中，对于记忆至关重要的大脑区域之间的相互作用如何变化。我们对 77 名年龄在 8-16 岁的个体进行了功能磁共振成像，将他们分为年龄较小（8-10 岁）和年龄较大（年龄大于 11 岁）的两组，使用偶然编码记忆任务来激活海马体形成和相关的大脑网络，以及记忆功能的行为数据。我们对四个组（年龄较小的女孩、年龄较小的男孩、年龄较大的女孩和年龄较大的男孩）的影像数据进行了 SEM 分析，然后使用堆叠模型方法对这些组进行了比较。这些模型之间存在显著差异。年龄较小的男孩的连接主要来自初级视觉区域，并终止于多模态处理区域，其分布主要在后侧。年龄较大的男孩的连接分布相对靠前，在关联和多模态处理区域内的有效连接增加。年龄较小的女孩的连接模式与年龄较大的男孩相似，在感觉、多模态和边缘区域之间存在一个大致从前到后的网络。相比之下，年龄较大的女孩的连接分布广泛但相对较弱。记忆表现随年龄增长而提高，且性别之间无显著差异。这些发现表明，在女孩和男孩中，从年龄较小的个体到年龄较大的个体，大脑区域之间存在着一种逐渐的重组，认知功能的效率也相应提高，为理解这一关键过渡时期发挥作用的年龄和性别特定过程提供了线索。
