title: The impact of parent socio-economic status on executive functioning and cortical morphology in individuals with schizophrenia and healthy controls.
abstract: BACKGROUND
  Relatively lower executive functioning is characteristic of individuals with schizophrenia. As low socio-economic status (SES) early in life (i.e. parent SES) has been linked with lower executive skills in healthy children, we hypothesized that parental SES (pSES) would be more strongly related to executive functioning in individuals with schizophrenia than in controls and have a greater impact on prefrontal cortical morphology.
  
  
  METHODS
  Healthy controls (n = 125) and individuals with schizophrenia (n = 102) completed tests assessing executive functioning and intelligence. The groups were matched on pSES, which was evaluated with the Hollingshead-Redlich scale. A principal components analysis (PCA) was conducted on 10 variables from six executive tests, yielding three specific components (fluency, planning and response inhibition). Voxel-based morphometry (VBM) was used to evaluate effects of pSES on gray matter (GM) concentration.
  
  
  RESULTS
  Lower pSES was associated with lower scores across the three executive functioning components, and a significant group by pSES interaction was observed such that low pSES, in particular, affected individuals with schizophrenia. These effects remained significant when intellectual ability, education and self-SES (sSES) were added as covariates. VBM revealed that lower pSES was associated with reduced GM volume in several anterior brain regions, especially the superior frontal gyrus, in patients but not in controls.
  
  
  CONCLUSIONS
  These findings suggest that individuals with schizophrenia may be particularly vulnerable to the adverse impact of low pSES, in terms of both lower executive skills and reduced anterior GM volumes.
authors.affiliation: Department of Psychology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Yeo
authors.affiliation: Department of Psychology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: D
authors.initials: D
authors.lastname: Martinez
authors.affiliation: Department of Psychology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: J
authors.initials: J
authors.lastname: Pommy
authors.affiliation: Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ehrlich
authors.affiliation: Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Schulz
authors.affiliation: Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
authors.forename: B-C
authors.initials: BC
authors.lastname: Ho
authors.affiliation: The Mind Research Network, Albuquerque, NM, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Bustillo
authors.affiliation: The Mind Research Network, Albuquerque, NM, USA.
authors.forename: V D
authors.initials: VD
authors.lastname: Calhoun
mesh_terms: D000328:Adult; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010290:Parents; D017397:Prefrontal Cortex / Q000473:pathology*; D012559:Schizophrenia / Q000473:pathology / Q000503:physiopathology*; D012923:Social Class