Alcohol intoxication effects on visual perception: An fMRI study

Abstract

We examined the effects of two doses of alcohol (EtOH) on functional magnetic resonance imaging (fMRI) activation during a visual perception task. The Motor-Free Visual Perception Test-Revised (MVPT-R) provides measures of overall visual perceptual processing ability. It incorporates different cognitive elements including visual discrimination, spatial relationships, and mental rotation. We used the MVPT-R to study brain activation patterns in healthy controls (1) sober, and (2) at two doses of alcohol intoxication with event-related fMRI. The fMRI data were analyzed using a general linear model approach based upon a model of the time course and a hemodynamic response estimate. Additionally, a correlation analysis was performed to examine dose-dependent amplitude changes. With regard to alcohol-free task-related brain activation, we replicate our previous finding in which SPM group analysis revealed robust activation in visual and visual association areas, frontal eye field (FEF)/dorsolateral prefrontal cortex (DLPFC), and the supplemental motor area (SMA). Consistent with a previous study of EtOH and visual stimulation, EtOH resulted in a dose-dependent decrease in activation amplitude over much of the visual perception network and in a decrease in the maximum contrast-to-noise ratio (in the lingual gyrus). Despite only modest behavior changes (in the expected direction), significant dose-dependent activation increases were observed in insula, DLPFC, and precentral regions, whereas dose-dependent activation decreases were observed in anterior and posterior cingulate, precuneus, and middle frontal areas. Some areas (FEF/DLPFC/SMA) became more diffusely activated (i.e., increased in spatial extent) at the higher dose. Alcohol, thus, appears to have both global and local effects upon the neural correlates of the MVPT-R task, some of which are dose dependent.

Alcohol Intoxication Effects on Simulated Driving: Exploring Alcohol-Dose Effects on Brain Activation Using Functional MRI

“…Second, we expected to replicate our previous findings with regard to the driving-related components. Third, we expected a global dose-related decrease in fMRI signal (as we found in a previous analysis of a different task; Calhoun et al, 2004). Fourth, we expected to find component-specific EtOH-related disruptions in the temporal dynamics revealed by ICA, specifically in frontal regions and cerebellum.…”

“…in some regions as well as dose-related changes (both increases and decreases) in other regions (Calhoun et al, 2004), suggesting that the global EtOH effect may be a function of the task used.…”

Investigating the effects of low dose alcohol on neural timing using functional MRI

“…This neural structure is most commonly activated during periods of sustained visuospatial processing (22), maintaining concentration on a shifting target (23), and in reorienting one's own proprioception to a changing environment (24). In some precarious situations (e.g., adjusting to traffic lights while driving), an impairment of the functions just mentioned could result in dangerous outcomes due to diminished capabilities in the mental coordination of vision, timing, and motor tasks (25). The increased activation in the Post-Drink state may therefore reflect an increased demand for recruiting extra cognitive resources essential to repeat an equivalent task performance after alcohol consumption.…”

AMPA Receptor Potentiation can Prevent Ethanol-Induced Intoxication

“…Studies examining ethanol's effects using changes in cerebral heamodynamics as markers of brain activity have provided somewhat conflicting results. Human fMRI studies have shown reduced activity in visual regions in response to photic stimulation (Levin et al, 1998) and visual perception tests (Calhoun et al, 2004) following alcohol, whereas both global and localized increases in regional cerebral blood flow have been observed in humans (Newlin et al, 1982;Tiihonen et al, 1994) and rats (Lyons et al, 1998) after ethanol challenge. One intrinsic confound for such studies is that ethanol itself is vasoactive rendering it potentially difficult to separate its direct effects on the vasculature from neurogenic effects.…”