title: Explore the Functional Connectivity between Brain Regions during a Chemistry Working Memory Task.
abstract: Previous studies have rarely examined how temporal dynamic patterns, event-related coherence, and phase-locking are related to each other. This study assessed reaction-time-sorted spectral perturbation and event-related spectral perturbation in order to examine the temporal dynamic patterns in the frontal midline (F), central parietal (CP), and occipital (O) regions during a chemistry working memory task at theta, alpha, and beta frequencies. Furthermore, the functional connectivity between F-CP, CP-O, and F-O were assessed by component event-related coherence (ERCoh) and component phase-locking (PL) at different frequency bands. In addition, this study examined whether the temporal dynamic patterns are consistent with the functional connectivity patterns across different frequencies and time courses. Component ERCoh/PL measured the interactions between different independent components decomposed from the scalp EEG, mixtures of time courses of activities arising from different brain, and artifactual sources. The results indicate that the O and CP regions' temporal dynamic patterns are similar to each other. Furthermore, pronounced component ERCoh/PL patterns were found to exist between the O and CP regions across each stimulus and probe presentation, in both theta and alpha frequencies. The consistent theta component ERCoh/PL between the F and O regions was found at the first stimulus and after probe presentation. These findings demonstrate that temporal dynamic patterns at different regions are in accordance with the functional connectivity patterns. Such coordinated and robust EEG temporal dynamics and component ERCoh/PL patterns suggest that these brain regions' neurons work together both to induce similar event-related spectral perturbation and to synchronize or desynchronize simultaneously in order to swiftly accomplish a particular goal. The possible mechanisms for such distinct component phase-locking and coherence patterns were also further discussed.
authors.affiliation: Institute of Education, National Chiao-Tung University, Hsinchu, Taiwan.
authors.forename: Wen-Chi
authors.initials: WC
authors.lastname: Chou
authors.affiliation: Biomedical Engineering Research Center and Graduate Institute of Clinical and Medical Science, China Medical University, Taichung, Taiwan; Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California, San Diego, San Diego, CA, United States of America.
authors.forename: Jeng-Ren
authors.initials: JR
authors.lastname: Duann
authors.affiliation: Institute of Education, National Chiao-Tung University, Hsinchu, Taiwan.
authors.forename: Hsiao-Ching
authors.initials: HC
authors.lastname: She
authors.affiliation: Institute of Education, National Chiao-Tung University, Hsinchu, Taiwan.
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Huang
authors.affiliation: Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California, San Diego, San Diego, CA, United States of America.
authors.forename: Tzyy-Ping
authors.initials: TP
authors.lastname: Jung
mesh_terms: D000293:Adolescent; D000513:Alpha Rhythm / Q000502:physiology; D001611:Beta Rhythm / Q000502:physiology; D001931:Brain Mapping; D002621:Chemistry / Q000193:education; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D009778:Occipital Lobe / Q000033:anatomy & histology / Q000502:physiology*; D010296:Parietal Lobe / Q000033:anatomy & histology / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013647:Task Performance and Analysis; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology*; D013826:Theta Rhythm / Q000502:physiology; D055815:Young Adult