title: Decoupling of reaction time-related default mode network activity with cognitive demand.
abstract: Reaction Time (RT) is associated with increased amplitude of the Blood Oxygen-Level Dependent (BOLD) response in task positive regions. Few studies have focused on whether opposing RT-related suppression of task activity also occurs. The current study used two Go/No-go tasks with different cognitive demands to examine regions that showed greater BOLD suppression for longer RT trials. These RT-related suppression effects occurred within the DMN and were task-specific, localizing to separate regions for the two tasks. In the task requiring working memory, RT-related de-coupling of the DMN occurred. This was reflected by opposing RT-BOLD effects for different DMN regions, as well as by reduced positive RT-related Psycho-Physiological Interaction (PPI) connectivity within the DMN and a lack of negative RT-related PPI connectivity between DMN and task positive regions. The results suggest that RT-related DMN suppression is task-specific. RT-related de-coupling of the DMN with more complex task demands may contribute to lapses of attention and performance decrements that occur during cognitively-demanding tasks.
authors.affiliation: Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY, 11030, USA. adbarber@gmail.com.
authors.forename: Anita D
authors.initials: AD
authors.lastname: Barber
authors.affiliation: Johns Hopkins School of Public Health, 615 North Wolfe Street, Baltimore, MD, 21205, USA.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Caffo
authors.affiliation: Kennedy Krieger Institute, 707 N. Broadway, Baltimore, MD, 21205, USA.|Johns Hopkins School of Medicine, 733 N. Broadway, Baltimore, MD, 21205, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Pekar
authors.affiliation: Kennedy Krieger Institute, 707 N. Broadway, Baltimore, MD, 21205, USA.|Johns Hopkins School of Medicine, 733 N. Broadway, Baltimore, MD, 21205, USA.
authors.forename: Stewart H
authors.initials: SH
authors.lastname: Mostofsky
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000502:physiology; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology*; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Anti-correlation; Attention; Default mode network; Reaction times