title: Examining the frontal subcortical brain vulnerability hypothesis in children with neurofibromatosis type 1: Are T2-weighted hyperintensities related to executive dysfunction?
abstract: OBJECTIVE
  It was hypothesized that neuropsychological impairments in children with neurofibromatosis type I (NF1) are associated with brain areas of increased T2-weighted signal intensity on MRI. Systematic and extensive examination of this hypothesis remains however scarce, particularly regarding executive dysfunction whereas hyperintensities are located preferentially in frontal-sub-cortical networks. In this study, we compared the executive functioning profile with characteristics of brain hyperintensities in children with NF1.
  
  
  METHODS
  A sample of 36 school-age children with NF1 (7-12 years) underwent a detailed examination of executive function, including performance-based tests and child's behavior rating in daily life. Executive function measures were compared with the characteristics of the T2-weighted hyperintensities on parallel MRI scans. The presence, number, and size of hyperintensities in the whole brain were considered as well as their main cerebral locations.
  
  
  RESULTS
  Executive dysfunction including traditional cognitive and ecological measures in children with NF1 is not significantly influenced by T2-weighted hyperintensities, in terms of presence or not, number, size, and location, whether in the whole brain or according to involved specific brain areas.
  
  
  CONCLUSIONS
  T2-weighted hyperintensities, as they are currently measured, cannot be used as a strong indicator of executive dysfunction in children with NF1. Based on the available NF1 cognitive impairment pathogenesis models, a critical discussion on anatomical-functional relationships between hyperintensities and neuropsychological profile is proposed, especially the executive dysfunction.
authors.affiliation: Psychology Laboratory, LUNAM, Angers University.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Roy
authors.affiliation: Neurofibromatosis Clinic, Nantes University Hospital.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Barbarot
authors.affiliation: Reference Center for Learning Disabilities, Nantes University Hospital.
authors.forename: Valérie
authors.initials: V
authors.lastname: Charbonnier
authors.affiliation: Neurofibromatosis Clinic, Nantes University Hospital.
authors.forename: Marie
authors.initials: M
authors.lastname: Gayet-Delacroix
authors.affiliation: Neurofibromatosis Clinic, Nantes University Hospital.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Stalder
authors.affiliation: Neurocognition and Psychology Laboratory, Savoie University.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Roulin
authors.affiliation: Psychology Laboratory, LUNAM, Angers University.
authors.forename: Didier
authors.initials: D
authors.lastname: Le Gall
mesh_terms: D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D002648:Child; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology / Q000523:psychology; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009456:Neurofibromatosis 1 / Q000150:complications* / Q000473:pathology / Q000523:psychology; D009483:Neuropsychological Tests