title: Learning Effective Connectivity Network Structure from fMRI Data Based on Artificial Immune Algorithm.
abstract: Many approaches have been designed to extract brain effective connectivity from functional magnetic resonance imaging (fMRI) data. However, few of them can effectively identify the connectivity network structure due to different defects. In this paper, a new algorithm is developed to infer the effective connectivity between different brain regions by combining artificial immune algorithm (AIA) with the Bayes net method, named as AIAEC. In the proposed algorithm, a brain effective connectivity network is mapped onto an antibody, and four immune operators are employed to perform the optimization process of antibodies, including clonal selection operator, crossover operator, mutation operator and suppression operator, and finally gets an antibody with the highest K2 score as the solution. AIAEC is then tested on Smith's simulated datasets, and the effect of the different factors on AIAEC is evaluated, including the node number, session length, as well as the other potential confounding factors of the blood oxygen level dependent (BOLD) signal. It was revealed that, as contrast to other existing methods, AIAEC got the best performance on the majority of the datasets. It was also found that AIAEC could attain a relative better solution under the influence of many factors, although AIAEC was differently affected by the aforementioned factors. AIAEC is thus demonstrated to be an effective method for detecting the brain effective connectivity.
authors.affiliation: Beijing Municipal Key Laboratory of Multimedia and Intelligent Software, College of Computer Science and Technology, Beijing University of Technology, Beijing, China.
authors.forename: Junzhong
authors.initials: J
authors.lastname: Ji
authors.affiliation: Beijing Municipal Key Laboratory of Multimedia and Intelligent Software, College of Computer Science and Technology, Beijing University of Technology, Beijing, China.
authors.forename: Jinduo
authors.initials: J
authors.lastname: Liu
authors.affiliation: Beijing Key Lab of MRI and Brain Informatics, Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China.
authors.forename: Peipeng
authors.initials: P
authors.lastname: Liang
authors.affiliation: Department of Computer Science and Engineering, University at Buffalo, The State University of New York, Buffalo, United States of America.
authors.forename: Aidong
authors.initials: A
authors.lastname: Zhang
mesh_terms: D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology; D063132:Connectome; D006801:Humans; D008279:Magnetic Resonance Imaging; D018448:Models, Immunological; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D011859:Radiography