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

Abstract

To examine human brain function related to the perception of short time intervals before and after ingesting a low dosage of alcohol (0.25 g/kg). The experiment used a novel paradigm that required participants to view a virtual traffic-light (TL) stimulus while estimating the length of a short time interval (Timing task) and counting several flashes (Counting task). The influence of alcohol was evaluated by measuring behavioral performance in terms of accuracy and reaction time as well as simultaneously measuring changes in the blood oxygenation level-dependent (BOLD) signal using functional MRI. Our results indicated that, for both the Pre-Drink and Post-Drink conditions, the left cerebellum, right inferior parietal lobe, right insula, and medial frontal gyrus, revealed greater BOLD signal increases for Timing than for Counting. In the Pre-Drink state, the Timing task demonstrated increased BOLD signal changes relative to the Counting task in the bilateral prefrontal cortex, left insula, right SMA, and in the left ventrolateral thalamus. Most notably, the right superior parietal lobe (BA 5/7) showed a BOLD signal increase in the Post-Drink state for both the Counting and Timing tasks, thus possibly suggesting the recruitment of additional resources to sustain accurate neural timing. Understanding the harmful impact of short-term alcohol administration on tasks that heavily rely on accurate temporal processing will hopefully contribute to the long-term prevention of its unfortunate and deleterious consequences.