Facultat de Psicologia, Universitat de Barcelona, Institut de Neurociències, Institute of Complex Systems (UBICS), Barcelona, Spain.
Facultad de Psicología, Universidad Michoacana de San Nicolás de Hidalgo, Francisco, Michoacán, México.
PLoS One. 2018 Nov 29;13(11):e0208247. doi: 10.1371/journal.pone.0208247. eCollection 2018.
Type 1 diabetes mellitus (T1D) affects the entire cellular network of the organism. Some patients develop cognitive disturbances due to the disease, but several authors have suggested that the brain develops compensatory mechanisms to minimize or prevent neuropsychological decline. The present study aimed to assess the effective connectivity underlying visuospatial working memory performance in young adults diagnosed with T1D using neuroimaging techniques (fMRI).
Fifteen T1D right-handed, young adults with sustained metabolic clinical stability and a control group matched by age, sex, and educational level voluntarily participated. All participants performed 2 visuospatial working memory tasks using a block design within an MRI scanner. Regions of interest and their signal values were obtained. Effective connectivity-by means of structural equations models-was evaluated for each group and task through maximum likelihood estimation, and the model with the best fit was chosen in each case.
Compared to the control group, the patient group showed a significant reduction in brain activity in the two estimated networks (one for each group and task). The models of effective connectivity showed greater brain connectivity in healthy individuals, as well as a more complex network. T1D patients showed a pattern of connectivity mainly involving the cerebellum and the red nucleus. In contrast, the control group showed a connectivity network predominantly involving brain areas that are typically activated while individuals are performing working memory tasks.
Our results suggest a specific effective connectivity between the cerebellum and the red nucleus in T1D patients during working memory tasks, probably reflecting a compensatory mechanism to fulfill task demands.
1 型糖尿病（T1D）影响机体的整个细胞网络。一些患者由于疾病而出现认知障碍，但有几位作者提出，大脑会发展出补偿机制，以最小化或预防神经心理衰退。本研究旨在使用神经影像学技术（fMRI）评估年轻的 T1D 患者在进行视空间工作记忆任务时的有效连接。
15 名 T1D 右利手年轻成年人，其代谢临床稳定持续，且与年龄、性别和教育水平相匹配的对照组自愿参与。所有参与者在 MRI 扫描仪内使用块设计执行 2 项视空间工作记忆任务。获得感兴趣区域及其信号值。通过最大似然估计，对每个组和任务进行有效连接的结构方程模型评估，并在每种情况下选择最佳拟合模型。
与对照组相比，患者组在两个估计网络（每个组和任务一个）中的大脑活动显著减少。有效连接模型显示，健康个体的大脑连接性更强，网络更复杂。T1D 患者的连接模式主要涉及小脑和红核。相比之下，对照组显示出的连接网络主要涉及在执行工作记忆任务时通常被激活的大脑区域。
我们的研究结果表明，在进行工作记忆任务时，T1D 患者的小脑和红核之间存在特定的有效连接，这可能反映了一种补偿机制，以满足任务需求。
