Diffusion-weighted magnetic resonance imaging at 3.0 Tesla in alcohol intoxication.
ABSTRACT Acute alcohol intake has pronounced effects on brain function. However, the exact mechanism of action is unclear. Diffusion Magnetic Resonance Imaging (dwMRI) can detect subtle changes in microstructural neural states. Here we tested if dwMRI can detect such changes during alcohol intoxication. We used high-field dwMRI in four healthy subjects at different blood alcohol concentration (0.0 g/L, 0.3 g/L, 0.6 g/L and 1.0 g/L). Although neuropsychological performances declined markedly, no changes in diffusion parameters emerged. First, this finding argues against alcohol-induced diffuse changes of microstructural state and in favour of more specific, possibly receptor-mediated actions of alcohol on brain function. Second, processes involving neurotransmitters that are primarily linked to cognitive function might not be viewable with high-field diffusion MRI.
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ABSTRACT: Alcohol has been shown to affect performance on tasks associated with executive functioning. However, studies in this area have generally been limited to a single dose or gender or have used small sample sizes. The purpose of this study was to provide a more nuanced and systematic examination of alcohol's effects on commonly used tests of executive functioning at multiple dosages in both men and women. Research volunteers (91 women and 94 men) were randomly assigned to one of four drink conditions (alcohol doses associated with target blood alcohol concentrations of .000%, .050%, .075%, and .100%). Participants then completed three tasks comprising two domains of executive functioning: two set shifting tasks, the Trail Making Test and a computerized version of the Wisconsin Card Sorting Task, and a response inhibition task, the GoStop Impulsivity Paradigm. Impaired performance on set shifting tasks was found at the .100% and .075% dosages, but alcohol intoxication did not impair performance on the GoStop. No gender effects emerged. Thus, alcohol negatively affects set shifting at moderately high levels of intoxication in both men and women, likely attributable to alcohol's interference with prefrontal cortex function. Although it is well established that alcohol negatively affects response inhibition as measured by auditory stop-signal tasks, alcohol does not appear to exert a negative effect on response inhibition as measured by the GoStop, a visual stop-signal task.Experimental and Clinical Psychopharmacology 10/2010; 18(5):409-17. · 2.55 Impact Factor
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ABSTRACT: We assessed the suitability of six applied tests of cognitive functioning to provide a single marker for dose-related alcohol intoxication. Numerous studies have demonstrated that alcohol has a deleterious effect on specific areas of cognitive processing but few have compared the effects of alcohol across a wide range of different cognitive processes. Adult participants (N = 56, 32 males, 24 females aged 18-45 years) were randomized to control or alcohol treatments within a mixed design experiment involving multiple-dosages at approximately one hour intervals (attained mean blood alcohol concentrations (BACs) of 0.00, 0.048, 0.082 and 0.10%), employing a battery of six psychometric tests; the Useful Field of View test (UFOV; processing speed together with directed attention); the Self-Ordered Pointing Task (SOPT; working memory); Inspection Time (IT; speed of processing independent from motor responding); the Traveling Salesperson Problem (TSP; strategic optimization); the Sustained Attention to Response Task (SART; vigilance, response inhibition and psychomotor function); and the Trail-Making Test (TMT; cognitive flexibility and psychomotor function). Results demonstrated that impairment is not uniform across different domains of cognitive processing and that both the size of the alcohol effect and the magnitude of effect change across different dose levels are quantitatively different for different cognitive processes. Only IT met the criteria for a marker for wide-spread application: reliable dose-related decline in a basic process as a function of rising BAC level and easy to use non-invasive task properties.PLoS ONE 01/2012; 7(11):e50977. · 3.73 Impact Factor