The general trend observed across studies indicates that adults with a variety of psychopathologies, neurological disorders, and typical age-related deficits exhibit abnormal PFC GM morphometry including volume, surface area, cortical thickness and folding, as well as fractional anisotropy (FA) measured via diffusion tensor imaging (DTI), which has been related to white matter integrity, compared to healthy controls ( Antonova et al. Of these studies, the vast majority has interrogated GM morphometry/EF relationships in cognitively impaired, clinical and aging populations, leaving the nature of these relationships in healthy young adults widely unexplored. Studies examining the associations between grey matter (GM) morphometry and EF have yielded variable results, suggesting highly complex, dynamic relationships between multiple morphometric measures and EF, which are modulated by age and clinical status. An abundance of lesion studies and those employing functional MRI implicates the pre-frontal cortex (PFC) as the main neuroanatomical region involved in EF ( Alvarez and Emory 2006 Jurado and Rosselli 2007 Miller and Cohen 2001 Stuss and Alexander 2000), though the relationship between individual differences in regional PFC morphometry and executive function remains underspecified. Despite the vital role of EF and its ubiquity in behavioral control, there exists an incomplete understanding of the psychological constructs and neural mechanisms supporting EF. These results suggest that the neural mechanisms supporting distinct aspects of EF may differentially rely on distinct regions of the PFC, and at least in healthy young adults, are influenced by regional morphometry of the PFC and the FA of major white matter tracts that connect the PFC with posterior cortical and subcortical regions.Įxecutive function (EF) is widely characterized as higher-order cognitive processes enabling one to flexibly control goal-oriented behavior.
Increased white matter FA in fiber tracts that connect the vmPFC and vlPFC with posterior regions of the brain also predicted better common EF and shifting-specific performance, respectively.
Despite capturing different components of GM morphometry, voxel- and surface-based findings were highly related, exhibiting regionally overlapping relationships with EF. Reductions in both GM volume (VBM) and cortical folding (SBM) in the ventromedial PFC (vmPFC), ventrolateral PFC (vlPFC), and dorsolateral PFC (dlPFC) predicted better common EF, shifting-specific, and updating-specific performance, respectively. Using optimized voxel-based morphometry (VBM), surface-based morphometry (SBM), and fractional anisotropy (FA) we determined the association between regional PFC grey matter (GM) morphometry and white matter tract diffusivity with performance on tasks that tap different aspects of EF as drawn from Miyake et al.’s three-factor model of EF. Although the relationship between structural differences within the prefrontal cortex (PFC) and executive function (EF) has been widely explored in cognitively impaired populations, little is known about this relationship in healthy young adults.
0 kommentar(er)
