title: The relationship between performance and fMRI signal during working memory in patients with schizophrenia, unaffected co-twins, and control subjects.
abstract: While behavioral research shows working memory impairments in schizophrenics and their relatives, functional neuroimaging studies of patients and healthy controls show conflicting findings of hypo- and hyperactivation, possibly indicating different relationships between physiological activity and performance. In a between-subjects regression analysis of fMRI activation and performance, low performance was associated with relatively lower activation in patients than controls, while higher performance was associated with higher activation in patients than controls in DLPFC and parietal cortex, but not occipital cortex, with unaffected twins of schizophrenics being intermediate between the groups. Accordingly, this supports the idea that both hyper and hypoactivation may be possible along a continuum of behavioral performance in a way consistent with a neural inefficiency model. Further, this study offers preliminary evidence that the relationship between behavior and physiology in schizophrenia may be heritable.
authors.affiliation: Department of Psychology, UCLA, Los Angeles, CA 90095-1563, USA.
authors.forename: Katherine H
authors.initials: KH
authors.lastname: Karlsgodt
authors.forename: David C
authors.initials: DC
authors.lastname: Glahn
authors.forename: Theo G M
authors.initials: TG
authors.lastname: van Erp
authors.forename: Sebastian
authors.initials: S
authors.lastname: Therman
authors.forename: Matti
authors.initials: M
authors.lastname: Huttunen
authors.forename: Marko
authors.initials: M
authors.lastname: Manninen
authors.forename: Jaakko
authors.initials: J
authors.lastname: Kaprio
authors.forename: Mark S
authors.initials: MS
authors.lastname: Cohen
authors.forename: Jouko
authors.initials: J
authors.lastname: Lönnqvist
authors.forename: Tyrone D
authors.initials: TD
authors.lastname: Cannon
mesh_terms: D000368:Aged; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D003118:Color Perception / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology; D004200:Diseases in Twins / Q000235:genetics* / Q000503:physiopathology*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005387:Finland; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009778:Occipital Lobe / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000503:physiopathology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012559:Schizophrenia / Q000235:genetics* / Q000503:physiopathology*
chemical_list: D010100:Oxygen