title: Lateralized resting-state functional connectivity in the task-positive and task-negative networks.
abstract: Studies on functional brain lateralization using functional magnetic resonance imaging (fMRI) have generally focused on lateralization of local brain regions. To explore the lateralization on the whole-brain level, lateralization of functional connectivity using resting-state fMRI (N=87, right handed) was analyzed and left- and right-lateralized networks were mapped. Four hundred two equally spaced regions of interest (ROI) covering the entire gray matter were divided into 358 task-positive and 44 task-negative ROIs. Lateralization of functional connectivity was analyzed separately for the task-positive and task-negative regions to prevent spuriously high lateralization indices caused by negative correlations between task-positive and task-negative regions. Lateralized functional connections were obtained using k-means clustering analysis. Within the task-positive network, the right-lateralized functional connections were between the occipital and inferior/middle frontal regions among other connections, whereas the left-lateralized functional connections were among fusiform gyrus and inferior frontal and inferior/superior parietal regions. Within the task-negative network, the left-lateralized connections were mainly between the precuneus and medial prefrontal regions. Specific brain regions exhibited different left- or right-lateralized connections with other regions, which suggest the importance of reporting lateralized connections over lateralized seed regions. The mean lateralization indices of the left- and right-lateralized connections were correlated, suggesting that the lateralization of connectivity may result from complementary processes between the lateralized networks. The potential functions of the lateralized networks were discussed.
authors.affiliation: 1 New Jersey Institute of Technology , Newark, New Jersey.
authors.forename: Xin
authors.initials: X
authors.lastname: Di
authors.forename: Eun H
authors.initials: EH
authors.lastname: Kim
authors.forename: Peii
authors.initials: P
authors.lastname: Chen
authors.forename: Bharat B
authors.initials: BB
authors.lastname: Biswal
mesh_terms: D001921:Brain / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D009415:Nerve Net / Q000166:cytology / Q000502:physiology*; D012146:Rest / Q000502:physiology*; D055815:Young Adult
keywords: functional connectivity; hemispheric asymmetry; lateralization; resting state