Examining the frontal subcortical brain vulnerability hypothesis in children with neurofibromatosis type 1: Are T2-weighted hyperintensities related to executive dysfunction?

Neuropsychology. 2015 May;29(3):473-84. doi: 10.1037/neu0000151. Epub 2014 Nov 3.

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.

Method: 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.

Conclusion: 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.

MeSH terms

  • Brain / pathology*
  • Brain Mapping
  • Child
  • Cognition Disorders / etiology*
  • Cognition Disorders / pathology
  • Cognition Disorders / psychology
  • Executive Function / physiology*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Neurofibromatosis 1 / complications*
  • Neurofibromatosis 1 / pathology
  • Neurofibromatosis 1 / psychology
  • Neuropsychological Tests