Department of Cardiology, Boston Children's Hospital, Massachusetts, USA.
Am J Med Genet A. 2013 Sep;161A(9):2250-7. doi: 10.1002/ajmg.a.36075. Epub 2013 Aug 5.
Genetic syndromes resulting from molecular alterations of the RAS-MAPK signaling cascade have become the focus of heightened interest among behavioral scientists due to discoveries that proteins within this pathway play an important role in memory formation and consolidation. Individuals with Noonan syndrome (NS), caused by germline mutations in the RAS-MAPK pathway, exhibit wide variability in cognitive and memory skills. The current study aimed to characterize memory deficits that occur in some affected individuals as a key step toward understanding the neurocognitive effects of dysregulated Ras signaling. Learning and memory skills were assessed among 29 children and adolescents with NS using the Wide Range Assessment of Memory and Learning, Second Edition. Performance across subdomains (verbal memory, visual memory and working memory) was compared, as well as the effect of response type (free recall vs. recognition). For immediate memory, children with NS performed significantly better on verbal memory tasks than on visual memory or working memory tasks. For delayed memory, verbal free recall tasks that depend heavily on prefrontal-hippocampal networks were more challenging than recognition tasks that rely on more distributed temporal cortical regions. Additionally, verbal information presented in context was more easily retained than that presented in a rote format. The current study contributes to our knowledge of the effects of dysregulated RAS-MAPK signaling on the brain and behavior. Continued research on neurocognitive skills in NS has the potential to generate a novel conceptualization of how learning disabilities can arise from altered molecular processes within a specific biological pathway.
由于发现该途径中的蛋白质在记忆形成和巩固中起着重要作用,因此导致 RAS-MAPK 信号级联分子改变的遗传综合征已成为行为科学家关注的焦点。由于种系突变导致 RAS-MAPK 途径的努南综合征(NS)个体,其认知和记忆技能存在广泛的可变性。本研究旨在描述一些受影响个体中发生的记忆缺陷,作为理解失调 Ras 信号传导的神经认知影响的关键步骤。使用广泛的记忆和学习评估,第二版评估了 29 名患有 NS 的儿童和青少年的学习和记忆技能。比较了子域(言语记忆,视觉记忆和工作记忆)的表现,以及反应类型(自由回忆与识别)的影响。对于即时记忆,患有 NS 的儿童在言语记忆任务上的表现明显优于视觉记忆或工作记忆任务。对于延迟记忆,严重依赖前额叶 - 海马网络的言语自由回忆任务比依赖更分布式颞皮质区域的识别任务更具挑战性。此外,以语境呈现的言语信息比以机械格式呈现的信息更容易保留。本研究有助于我们了解失调的 RAS-MAPK 信号对大脑和行为的影响。继续对 NS 神经认知技能的研究有可能从特定生物途径内改变的分子过程产生学习障碍如何产生的新概念化。