Brain structure and function in neurofibromatosis type 1: current concepts and future directions

Neurofibromatosis type 1 (NF1) is a common neurogenetic condition associated with cognitive dysfunction and learning disability. Over the past decade, important and consistent findings have emerged that provide insight into the neurobiological correlates of NF1. In this review, we examine the structural and functional neuroimaging literature in individuals with NF1 and discuss findings that have emerged. Collectively, the studies reviewed here highlight structural and functional brain abnormalities as a feature of NF1 and that these abnormalities contribute to the cognitive impairments that are commonly seen. The most compelling structural finding has been an increase in total brain volume with additional areas of interest including the corpus callosum, cerebral asymmetries and differences in grey and white matter. Although the application of functional neuroimaging techniques in NF1 is in its infancy, early evidence suggests alterations in brain organisation for language and visuospatial function as well as thalamic hypometabolism. Suggestions for future research are discussed, including the importance of addressing specific hypotheses in well-defined subsamples of children with NF1 using appropriate control groups. Identifying the underlying neuropathology of NF1 will be of increased importance as targeted interventions begin to emerge.