Rajabioun Mehdi, Motie Nasrabadi Ali, Shamsollahi Mohammad Bagher, Coben Robert
Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
Department of Biomedical Engineering, Faculty of Engineering, Shahed University, Tehran 3319118651, Iran.
Biomed Tech (Berl). 2020 Jan 28;65(1):23-32. doi: 10.1515/bmt-2019-0062.
Brain connectivity estimation is a useful method to study brain functions and diagnose neuroscience disorders. Effective connectivity is a subdivision of brain connectivity which discusses the causal relationship between different parts of the brain. In this study, a dual Kalman-based method is used for effective connectivity estimation. Because of connectivity changes in autism, the method is applied to autistic signals for effective connectivity estimation. For method validation, the dual Kalman based method is compared with other connectivity estimation methods by estimation error and the dual Kalman-based method gives acceptable results with less estimation errors. Then, connectivities between active brain regions of autistic and normal children in the resting state are estimated and compared. In this simulation, the brain is divided into eight regions and the connectivity between regions and within them is calculated. It can be concluded from the results that in the resting state condition the effective connectivity of active regions is decreased between regions and is increased within each region in autistic children. In another result, by averaging the connectivity between the extracted active sources of each region, the connectivity between the left and right of the central part is more than that in other regions and the connectivity in the occipital part is less than that in others.
脑连接估计是研究脑功能和诊断神经科学疾病的一种有用方法。有效连接是脑连接的一个细分领域，它讨论大脑不同部分之间的因果关系。在本研究中，一种基于双卡尔曼的方法被用于有效连接估计。由于自闭症患者存在连接性变化，该方法被应用于自闭症信号以进行有效连接估计。为了验证方法，通过估计误差将基于双卡尔曼的方法与其他连接估计方法进行比较，基于双卡尔曼的方法给出了可接受的结果且估计误差较小。然后，对自闭症儿童和正常儿童在静息状态下活跃脑区之间的连接性进行估计和比较。在这个模拟中，大脑被划分为八个区域，并计算区域之间以及区域内部的连接性。从结果可以得出，在静息状态下，自闭症儿童区域间活跃区域的有效连接性降低，而每个区域内的有效连接性增加。另一个结果是，通过对每个区域提取的活跃源之间的连接性进行平均，中央部分左右两侧的连接性比其他区域更强，枕叶部分的连接性比其他区域更弱。
