title: Altered executive function in the lead-exposed brain: A functional magnetic resonance imaging study.
abstract: BACKGROUND
  It is well known that lead exposure induces neurotoxic effects, which can result in dysfunction in a variety of cognitive capacities including executive function. However, few studies have used fMRI to examine the direct neural correlates of executive function in participants with past lead exposure. Therefore, this study aimed to investigate possible alterations in the neural correlates of executive function in the previously lead-exposed brain.
  
  
  METHODS
  Forty-three lead-exposed and 41 healthy participants were enrolled. During the fMRI scans, participants performed two modified versions of the Wisconsin Card Sorting Task (WCST) differing in cognitive demand, and a task that established a high-level baseline condition (HLB).
  
  
  RESULTS
  The neural activation of left dorsolateral prefrontal cortex was greater in healthy controls than in participants with lead exposure when contrasting the difficult version of the WCST with the HLB. Moreover, cortical activation was found to be inversely associated with blood lead concentration after controlling for covariates.
  
  
  CONCLUSIONS
  These data suggest that lead exposure can induce functional abnormalities in distributed cortical networks related to executive function, and that lead-induced neurotoxicity may be persistent rather than transient.
authors.affiliation: Department of Medical & Biological Engineering, Kyungpook National University, Daegu, South Korea.
authors.forename: Jeehye
authors.initials: J
authors.lastname: Seo
authors.affiliation: Korean Industrial Health Association, Seoul, South Korea.
authors.forename: Byung-Kook
authors.initials: BK
authors.lastname: Lee
authors.affiliation: Department of Medical & Biological Engineering, Kyungpook National University, Daegu, South Korea.
authors.forename: Seong-Uk
authors.initials: SU
authors.lastname: Jin
authors.affiliation: Department of Medical & Biological Engineering, Kyungpook National University, Daegu, South Korea.
authors.forename: Kyung Eun
authors.initials: KE
authors.lastname: Jang
authors.affiliation: Department of Medical & Biological Engineering, Kyungpook National University, Daegu, South Korea.
authors.forename: Jang Woo
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Psychiatry, School of Medicine, Keimyung University, Daegu, South Korea.
authors.forename: Yang-Tae
authors.initials: YT
authors.lastname: Kim
authors.affiliation: Department of Psychiatry, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, South Korea.
authors.forename: Sin-Jae
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Occupational and Environmental Medicine, Dongguk University College of Medicine, Dongguk University Ilsan Hospital, Goyang, South Korea.
authors.forename: Kyoung Sook
authors.initials: KS
authors.lastname: Jeong
authors.affiliation: Department of Occupational Health, Catholic University of Daegu, Daegu, South Korea.
authors.forename: Jungsun
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Neurology, Inje University Ilsan Paik Hospital, Goyang, South Korea.
authors.forename: Ahro
authors.initials: A
authors.lastname: Kim
authors.affiliation: Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, South Korea. Electronic address: yanghokm@nuri.net.
authors.forename: Yangho
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Medical & Biological Engineering, Kyungpook National University, Daegu, South Korea; Department of Radiology, Kyungpook National University School of Medicine, Daegu, South Korea; Department of Molecular Medicine, Kyungpook National University School of Medicine, Daegu, South Korea. Electronic address: ychang@knu.ac.kr.
authors.forename: Yongmin
authors.initials: Y
authors.lastname: Chang
mesh_terms: D001288:Attention / Q000187:drug effects; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000139:chemically induced*; D056344:Executive Function / Q000187:drug effects*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007854:Lead / Q000009:adverse effects* / Q000097:blood; D008279:Magnetic Resonance Imaging; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply* / Q000187:drug effects*; D012044:Regression Analysis
chemical_list: D007854:Lead; D010100:Oxygen
keywords: Executive function; Lead exposure; Wisconsin Card Sorting Task; fMRI