title: Hyperdeactivation of the Default Mode Network in People With Schizophrenia When Focusing Attention in Space.
abstract: When studying selective attention in people with schizophrenia (PSZ), a counterintuitive but replicated finding has been that PSZ display larger performance benefits than healthy control subjects (HCS) by cues that predicts the location of a target stimulus relative to non-predictive cues. Possible explanations are that PSZ hyperfocus attention in response to predictive cues, or that an inability to maintain a broad attentional window impairs performance when the cue is non-predictive. Over-recruitment of regions involved in top-down focusing of spatial attention in response to predictive cues would support the former possibility, and an inappropriate recruitment of these regions in response to non-predictive cues the latter. We probed regions of the dorsal attention network while PSZ (N = 20) and HCS (N = 20) performed a visuospatial attention task. A central cue either predicted at which of 4 peripheral locations a target signal would appear, or it gave no information about the target location. As observed previously, PSZ displayed a larger reaction time difference between predictive and non-predictive cue trials than HCS. Activity in frontoparietal and occipital regions was greater for predictive than non-predictive cues. This effect was almost identical between PSZ and HCS. There was no sign of over-recruitment when the cue was predictive, or of inappropriate recruitment when the cue was non-predictive. However, PSZ differed from HCS in their cue-dependent deactivation of the default mode network. Unexpectedly, PSZ displayed significantly greater deactivation than HCS in predictive cue trials, which may reflect a tendency to expend more processing resources when focusing attention in space.
authors.affiliation: Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD; bhahn@mprc.umaryland.edu.
authors.forename: Britta
authors.initials: B
authors.lastname: Hahn
authors.affiliation: Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD;
authors.forename: Alexander N
authors.initials: AN
authors.lastname: Harvey
authors.affiliation: Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD;
authors.forename: James M
authors.initials: JM
authors.lastname: Gold
authors.affiliation: Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD;
authors.forename: Bernard A
authors.initials: BA
authors.lastname: Fischer
authors.affiliation: Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD;
authors.forename: William R
authors.initials: WR
authors.lastname: Keller
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse-Intramural Research Program, Baltimore, MD.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Ross
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse-Intramural Research Program, Baltimore, MD.
authors.forename: Elliot A
authors.initials: EA
authors.lastname: Stein
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D003463:Cues; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology*; D013028:Space Perception / Q000502:physiology*; D055815:Young Adult
keywords: default network; fMRI; top-down