title: Age-related spatiotemporal reorganization during response inhibition.
abstract: As a key high-level cognitive function in human beings, response inhibition is crucial for adaptive behavior. Previous neuroimaging studies have shown that older individuals exhibit greater neural activation than younger individuals during response inhibition tasks. This finding has been interpreted within a neural compensation framework, in which additional neural resources are recruited in response to age-related cognitive decline. Although this interpretation has received empirical support, the precise event-related temporal course of this age-related compensatory neural response remains unexplored. In the present study, we conducted source analysis on inhibition-related ERP components (i.e., N2 and P3) that were recorded while healthy younger and older adults participated in a visual Go/NoGo task. We found that older adults showed increased source current densities of the N2 and P3 components than younger adults, which support previous hemodynamic findings. Further, such age-related differences in neural activation were successfully separated between the N2 and P3 periods by source localization analysis. Interestingly, the increased activations in older adults were primarily localized to the right precentral and postcentral gyri during the N2 period, which shifted to the right dorsolateral prefrontal cortex and the right inferior frontal gyrus during the P3 period. Taken together, our results clearly illustrate the spatiotemporal dynamics of age-related functional brain reorganization, and further specify the exact temporal course at the millisecond scale by which age-related compensatory neural responses occur during response inhibition.
authors.affiliation: School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Center for Mind and Brain, University of California-Davis, Davis CA 95618, USA.
authors.forename: Xiangfei
authors.initials: X
authors.lastname: Hong
authors.affiliation: School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Sun
authors.affiliation: Center for Mind and Brain, University of California-Davis, Davis CA 95618, USA.
authors.forename: Jesse J
authors.initials: JJ
authors.lastname: Bengson
authors.affiliation: School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: stong@sjtu.edu.cn.
authors.forename: Shanbao
authors.initials: S
authors.lastname: Tong
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D002755:Choice Behavior / Q000502:physiology; D003463:Cues; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
keywords: Aging; Event-related potentials; Go/NoGo; Response inhibition; Source localization