Tract-based spatial statistics (TBSS) of diffusion tensor imaging data in alcohol dependence: Abnormalities of the motivational neurocircuitry

Abstract

Previous diffusion tensor imaging (DTI) studies indicated microstructural disruption of white matter in alcohol dependence. To investigate the microstructure of primary neurocircuitry involved in alcohol use disorders, the present study used Tract-Based Spatial Statistics (TBSS) of DTI measures as well as probabilistic tractography. Eleven recovering alcoholics in their first week of abstinence from alcohol were compared with ten light drinking controls; diffusion measures were correlated with measures of neurocognition and drinking severity. Regions characterized by low fractional anisotropy and high mean diffusivity included cortico-striatal fibers and those in frontal white matter and limbic pathways. Greater diffusion abnormalities in sections of commissural fibers (interhemispheric connections) were associated with stronger drinking severity, and lower fractional anisotropy measures in frontal and limbic fiber tracts correlated with lower visuospatial memory performance. These study findings provide direct evidence of compromised integrity of the motivational brain circuitry in alcohol use disorders. These abnormalities in fiber connections could be partially responsible for deficiencies in executive functions, behavioral regulation, and impulse control commonly described in alcohol dependence.

Abnormal White Matter Integrity in Chronic Users of Codeine-Containing Cough Syrups: A Tract-Based Spatial Statistics Study

“…Loss of WM integrity in the corona radiata has been consistently observed in cocaine, 31 methamphetamine, 32 and alcohol dependence. 33 These findings are consistent with those of previous results. The significant negative correlation between the FA value of the right superior corona radiata and the BIS total score supports the conclusions of previous functional studies linking the parietal lobe to impulse control.…”

Intertemporal choice behavior is constrained by brain structure in healthy participants and pathological gamblers

“…Joutsa et al (2011) point out that similar changes have also been seen in substance abuse disorders (e.g., Lim et al 2008;Xu et al 2010). Further, the superior longitudinal fascicle (Lim et al 2008;Ashtari et al 2009;Jacobus et al 2009;Pfefferbaum et al 2009;Yeh et al 2009;Lane et al 2010;Xu et al 2010), the inferior longitudinal fascicle (Jacobus et al 2009;Yeh et al 2009) and the inferior fronto-occipital fascicle (Yeh et al 2009) have been seen in previous DTI studies pointing to a general susceptibility to addictions for subjects presenting with a reduced FA in these tracts. Studies in behavioral addictions such as the current one are particularly relevant, as the white matter changes in this case cannot exclusively be explained by direct effects of substances on white matter.…”

Diffusion Magnetic Resonance Imaging: From Isotropic Diffusion-Weighted Imaging to Diffusion Tensor Imaging and Beyond

“…The interpretations of DTI parameters are: 1) fractional anisotropy (FA) that describe the degree of anisotropy of a diffusion process, with values from 0 (isotropic) to 1 (anisotropic) 24) ; 2) mean diffusivity (MD); 3) radial diffusivity (RD); and 4) axial diffusivity (AD) 4) . FA reflects the axonal density, axonal integrity, and fiber tract complexity 25) . Reduced FA was found in many diseases, that is attributed to degradation of myelin sheaths and axonal membranes, or reduced density of axonal fibers 4) 25) .…”

“…Reduced FA was found in many diseases, that is attributed to degradation of myelin sheaths and axonal membranes, or reduced density of axonal fibers 4) 25) . MD, which is the mean-squared displacement of water molecules restricted by organelles and membranes, reflects cellular density and extracellular volume and relates to the volume fraction of the interstitial space 25) . Moreover, RD will increase in demyelination, edema will increase the MD, and cell proliferation will decrease the MD 4) .…”