title: Inefficiently increased anterior cingulate modulation of cortical systems during working memory in young offspring of schizophrenia patients.
abstract: BACKGROUND
  Children and adolescent offspring of schizophrenia patients are at increased risk for schizophrenia and are also characterized by impairments in brain structure and function. To date, few studies have investigated whether functional interactions between brain regions are intact or altered. Using an established verbal working memory paradigm with variable levels of memory load, we investigated the modulatory effect of activity in cognitive control regions of the brain (specifically the dorsal anterior cingulate cortex) on activity in core working memory regions, in particular the dorsal prefrontal cortex and the parietal lobe.
  
  
  METHODS
  Forty four subjects participated. An n-back task with two levels of working memory load (1- and 2-back) was employed during fMRI (4 T Bruker MedSpec system). Data were processed with SPM5 and the modulatory effects of the anterior cingulate were investigated using psycho-physiological interaction (PPI).
  
  
  RESULTS
  In spite of only subtle activation differences, and no significant differences in performance accuracy, a significant group x memory load interaction in the parietal lobe, indicated aberrantly increased modulatory inputs to this region under conditions of high working memory load in schizophrenia offspring.
  
  
  CONCLUSIONS
  Increased modulatory inputs from a central control region like the anterior cingulate presumably reflect relative inefficiency in intra-cortical interactions in the vulnerable brain. This inefficiency may reflect a developmentally mediated impairment in functional brain interactions in this important vulnerable population. It is highly plausible that the resultant effect of these altered interactions is an increased vulnerability to impaired brain development, and therefore to psychiatric disorders including schizophrenia.
authors.affiliation: Dept. of Psychiatry & Behavioral Neuroscience, Wayne State University SOM, MI 48201, USA.
authors.forename: Neil
authors.initials: N
authors.lastname: Bakshi
authors.forename: Patrick
authors.initials: P
authors.lastname: Pruitt
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Radwan
authors.forename: Matcheri S
authors.initials: MS
authors.lastname: Keshavan
authors.forename: Usha
authors.initials: U
authors.lastname: Rajan
authors.forename: Caroline
authors.initials: C
authors.lastname: Zajac-Benitez
authors.forename: Vaibhav A
authors.initials: VA
authors.lastname: Diwadkar
mesh_terms: D000293:Adolescent; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply*; D002648:Child; D016241:Child of Impaired Parents; D005260:Female; D006179:Gyrus Cinguli / Q000098:blood supply*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia; D055815:Young Adult
chemical_list: D010100:Oxygen