title: Variance maps as a novel tool for localizing regions of interest in imaging studies of individual differences.
abstract: Cognitive neuroimaging studies of individual differences seek to reveal brain mechanisms of cognition by associating intersubject variability in brain activation with other variables of interest, such as sex, personality trait, or mood state. The choice of a priori regions of interest (ROIs) raises problems, because the selection criterion is typically consistent activation across prior studies, suggesting little intersubject variability. Here, we introduce a novel approach for selecting regions that are defined on the basis of their variance characteristics, rather than on the basis of their location or because of theoretical expectations. These regions of variance (ROVs) constitute the search space with which to assess how much of the observed variance can be ascribed to specific variables of interest. We compare the ROI and ROV approaches by applying each to the same data set and suggest that the conjunction of both methods may yield the greatest likelihood of capturing the rich relation between brain and behavior, while limiting the search space for statistical analyses and minimizing false positive errors.
authors.affiliation: Stony Brook University, Stony Brook, New York 11794-2500, USA.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Omura
authors.forename: Arthur
authors.initials: A
authors.lastname: Aron
authors.forename: Turhan
authors.initials: T
authors.lastname: Canli
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect / Q000502:physiology; D001921:Brain / Q000033:anatomy & histology* / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007206:Individuality; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D001523:Mental Disorders / Q000503:physiopathology; D010100:Oxygen / Q000097:blood; D010551:Personality / Q000502:physiology; D010552:Personality Assessment / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D013223:Statistics as Topic
chemical_list: D010100:Oxygen