title: Quantification of the power changes in BOLD signals using Welch spectrum method during different single-hand motor imageries.
abstract: Motor imagery is an experimental paradigm implemented in cognitive neuroscience and cognitive psychology. To investigate the asymmetry of the strength of cortical functional activity due to different single-hand motor imageries, functional magnetic resonance imaging (fMRI) data from right handed normal subjects were recorded and analyzed during both left-hand and right-hand motor imagery processes. Then the average power of blood oxygenation level-dependent (BOLD) signals in temporal domain was calculated using the developed tool that combines Welch power spectrum and the integral of power spectrum approach of BOLD signal changes during motor imagery. Power change analysis results indicated that cortical activity exhibited a stronger power in the precentral gyrus and medial frontal gyrus with left-hand motor imagery tasks compared with that from right-hand motor imagery tasks. These observations suggest that right handed normal subjects mobilize more cortical nerve cells for left-hand motor imagery. Our findings also suggest that the approach based on power differences of BOLD signals is a suitable quantitative analysis tool for quantification of asymmetry of brain activity intensity during motor imagery tasks.
authors.affiliation: School of Electrical Engineering and Information, Sichuan University, Chengdu 610065, China; Bioimaging Core, Faculty of Health Sciences, University of Macau, Macau SAR, China. Electronic address: zhangjiang_@hotmail.com.
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Bioimaging Core, Faculty of Health Sciences, University of Macau, Macau SAR, China. Electronic address: zhenyuan@umac.mo.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: School of Foreign Studies, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.affiliation: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.affiliation: School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors.forename: Huafu
authors.initials: H
authors.lastname: Chen
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D003071:Cognition; D005625:Frontal Lobe / Q000473:pathology*; D006225:Hand / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009044:Motor Cortex / Q000502:physiology; D009048:Motor Skills; D009068:Movement / Q000502:physiology; D009488:Neurosciences; D010100:Oxygen / Q000097:blood*; D012984:Software; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Cerebral cortical asymmetry; Functional magnetic resonance imaging (fMRI); Motor imagery; Welch power spectrum