Gray Matter Alterations in Adults with Attention-Deficit/Hyperactivity Disorder Identified by Voxel Based Morphometry

Abstract

Background Gray and white matter volume deficits have been reported in many structural magnetic resonance imaging (MRI) studies of children with attention-deficit/hyperactivity disorder (ADHD); however, there is a paucity of structural MRI studies of adults with ADHD. This study used voxel based morphometry and applied an a priori region of interest approach based on our previous work, as well as from well-developed neuroanatomical theories of ADHD. Methods Seventy-four adults with DSM-IV ADHD and 54 healthy control subjects comparable on age, sex, race, handedness, IQ, reading achievement, frequency of learning disabilities, and whole brain volume had an MRI on a 1.5T Siemens scanner. A priori region of interest hypotheses focused on reduced volumes in ADHD in dorsolateral prefrontal cortex, anterior cingulate cortex, caudate, putamen, inferior parietal lobule, and cerebellum. Analyses were carried out by FSL-VBM 1.1. Results Relative to control subjects, ADHD adults had significantly smaller gray matter volumes in parts of six of these regions at p ≤ .01, whereas parts of the dorsolateral prefrontal cortex and inferior parietal lobule were significantly larger in ADHD at this threshold. However, a number of other regions were smaller and larger in ADHD (especially fronto-orbital cortex) at this threshold. Only the caudate remained significantly smaller at the family-wise error rate. Conclusions Adults with ADHD have subtle volume reductions in the caudate and possibly other brain regions involved in attention and executive control supporting frontostriatal models of ADHD. Modest group brain volume differences are discussed in the context of the nature of the samples studied and voxel based morphometry methodology.

Significant grey matter changes in a region of the orbitofrontal cortex in healthy participants predicts emotional dysregulation

“…These findings are in line with a well-powered study of ADHD that had controlled for affective dysfunctions (Seidman et al, 2011). In that study an increased volume of lObfc bilaterally and rACC was observed in ADHD patients compared with controls, in conjunction with the expected decreased volume in non-emotional attentional systems including dlPFC and cACC that has previously been welldescribed for ADHD patients.…”

“…There seems to be a link between structure and function in clinical states such as ADHD and BPD. For example, in ADHD, smaller GMV in dlPFC and cACC has been observed (Seidman et al, 2011), and these structures are less activated during attentional tasks in this group (Dickstein et al, 2006). Likewise, in BPD, smaller GMV has been observed in lObfc and rACC (Soloff et al, 2008(Soloff et al, , 2012 and these regions are less activated in emotional regulation for this group of patients (Wingenfeld et al, 2009;Schulze et al, 2011).…”

Grey matter volume differences associated with gender in children with attention-deficit/hyperactivity disorder: A voxel-based morphometry study

“…Here, the lack of significant finding in the basal ganglia may also be related to the characteristics of our ADHD sample, which included boys with no psychiatric comorbidity, no learning disorder and a mean IQ of 105.7. Indeed, high-functioning samples presumably exhibit more subtle brain alterations that may be difficult to detect at a corrected statistical thresholding (Seidman et al, 2011).…”

The effect of methylphenidate intake on brain structure in adults with ADHD in a placebo-controlled randomized trial

“…For region-of-interest-based (ROI) analyses we used ROIs from the cross-sectional study 33 based on an earlier study by Seidman and colleagues. 36 Because the GLM-flex toolbox does not allow small-volume correction for multiple comparisons within an ROI, we extracted all voxels from the ROIs and corrected for multiple comparisons using false discovery rate (FDR) correction across all voxels of the corresponding ROI. Figure 1 illustrates the selection process for the baseline sample.…”