title: Perfusion shift from white to gray matter may account for processing speed deficits in schizophrenia.
abstract: Reduced speed of cerebral information processing is a cognitive deficit associated with schizophrenia. Normal information processing speed (PS) requires intact white matter (WM) physiology to support information transfer. In a cohort of 107 subjects (47/60 patients/controls), we demonstrate that PS deficits in schizophrenia patients are explained by reduced WM integrity, which is measured using diffusion tensor imaging, mediated by the mismatch in WM/gray matter blood perfusion, and measured using arterial spin labeling. Our findings are specific to PS, and testing this hypothesis for patient-control differences in working memory produces no explanation. We demonstrate that PS deficits in schizophrenia can be explained by neurophysiological alterations in cerebral WM. Whether the disproportionately low WM integrity in schizophrenia is due to illness or secondary due to this disorder deserves further examination.
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Susan N
authors.initials: SN
authors.lastname: Wright
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: L Elliot
authors.initials: LE
authors.lastname: Hong
authors.affiliation: Oxford Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford, Oxford, United Kingdom.
authors.forename: Anderson M
authors.initials: AM
authors.lastname: Winkler
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Joshua
authors.initials: J
authors.lastname: Chiappelli
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Katie
authors.initials: K
authors.lastname: Nugent
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Florian
authors.initials: F
authors.lastname: Muellerklein
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Xioming
authors.initials: X
authors.lastname: Du
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.|Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Department of Psychology, University of Maryland, Baltimore County, Maryland.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Rowland
authors.affiliation: Department of Neurology, University of California, Los Angeles, California.
authors.forename: Danny J J
authors.initials: DJ
authors.lastname: Wang
authors.affiliation: Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland.|Department of Physics, University of Maryland, Baltimore County, Maryland.
authors.forename: Peter
authors.initials: P
authors.lastname: Kochunov
mesh_terms: D000328:Adult; D000465:Algorithms; D002560:Cerebrovascular Circulation; D056324:Diffusion Tensor Imaging; D005260:Female; D066128:Gray Matter / Q000098:blood supply*; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D010477:Perfusion; D011597:Psychomotor Performance; D012559:Schizophrenia / Q000134:cerebrospinal fluid / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012907:Smoking / Q000523:psychology; D013113:Spin Labels; D066127:White Matter / Q000098:blood supply*
chemical_list: D013113:Spin Labels
keywords: DTI-FA; acute change; attention; cognition; nicotine; processing speed; white matter