title: The Paradoxical Relationship between White Matter, Psychopathology and Cognition in Schizophrenia: A Diffusion Tensor and Proton Spectroscopic Imaging Study.
abstract: White matter disruption has been repeatedly documented in schizophrenia consistent with microstructural disorganization (reduced fractional anisotropy (FA)) and axonal dysfunction (reduced N-acetylaspartate NAAc). However, the clinical significance of these abnormalities is poorly understood. Diffusion tensor and proton spectroscopic imaging where used to assess FA, axial diffusivity and radial diffusivity (RD), and supra-ventricular white matter NAAc, respectively, in 64 schizophrenia and 64 healthy subjects. Schizophrenia patients had reduced FA across several regions, with additional regions where FA correlated positively with positive symptoms severity. These regions included genu, body and splenium of corpus callosum, anterior and superior corona radiata, superior longitudinal and inferior fronto-occipital fasciculi, and internal capsule. The FA/symptoms relationships corresponded with opposite correlations between RD and positive symptoms. The schizophrenia group (SP group) had progressively reduced NAAc with age, and NAAc correlated negatively with positive symptoms. Cognition correlated positively with both FA and NAAc in controls, whereas in the SP group it had a negative correlation with NAAc and no significant relationship with FA. Antipsychotic dose did not account for the results. Correlates of psychosis, cognitive and negative symptoms can be found in white matter. The significant correlations between positive symptoms in schizophrenia and diffusion and NAAc measures suggest decreased axonal density with increased glial cells and higher myelination in this subpopulation. A separate set of abnormal relationships between cognition and FA/RD, as well as with NAAc, converge to suggest that in schizophrenia, white matter microstructure supports the two core illness domains: psychosis and cognitive/negative symptoms.
authors: The Mind Research Network, University of New Mexico, Albuquerque, NM, USA.
authors: Arvind
authors: A
authors: Caprihan
authors: Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA.
authors: Thomas
authors: T
authors: Jones
authors: Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA.
authors: Hongji
authors: H
authors: Chen
authors: Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA.
authors: Nicholas
authors: N
authors: Lemke
authors: Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA.
authors: Christopher
authors: C
authors: Abbott
authors: Department of Mathematics and Statistics, University of New Mexico, Albuquerque, NM, USA.
authors: Clifford
authors: C
authors: Qualls
authors: 1] Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA [2] Department of Neurosciences, University of New Mexico, Albuquerque, NM, USA [3] New Mexico VA Health Care System, Albuquerque, NM, USA.
authors: Jose
authors: J
authors: Canive
authors: The Mind Research Network, University of New Mexico, Albuquerque, NM, USA.
authors: Charles
authors: C
authors: Gasparovic
authors: 1] Department of Psychiatry, University of New Mexico, Albuquerque, NM, USA [2] Department of Neurosciences, University of New Mexico, Albuquerque, NM, USA.
authors: Juan R
authors: JR
authors: Bustillo
mesh_terms: D000328:Adult; D000368:Aged; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D003072:Cognition Disorders / Q000209:etiology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011522:Protons; D011569:Psychiatric Status Rating Scales; D011599:Psychopathology; D012559:Schizophrenia / Q000150:complications / Q000473:pathology*; D012565:Schizophrenic Psychology; D019265:Spectroscopy, Near-Infrared; D013223:Statistics as Topic; D066127:White Matter / Q000378:metabolism* / Q000473:pathology*; D055815:Young Adult
chemical_list: D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate