Change in brain asymmetry reflects level of acute alcohol intoxication and impacts on inhibitory control

Abstract

Alcohol is one of the most commonly used substances and frequently abused, yet little is known about the neural underpinnings driving variability in inhibitory control performance after ingesting alcohol. This study was a single-blind, placebo-controlled, randomized design with participants (N = 48 healthy, social drinkers) completing three study visits. At each visit participants received one of three alcohol doses; namely, a placebo dose [equivalent Blood Alcohol Concentration (BAC) = 0.00%], a low dose of alcohol (target BAC = 0.04%), or a moderate dose of alcohol (target BAC = 0.08%). To measure inhibitory control, participants completed a Go/No-go task paradigm twice during each study visit, once immediately before dosing and once after, while their brain activity was measured with time-domain functional near-infrared spectroscopy (TD-fNIRS). BAC and subjective effects of alcohol were also assessed. We report decreased behavioral performance for the moderate dose of alcohol, but not the low or placebo doses. We observed right lateralized inhibitory prefrontal activity during go-no-go blocks, consistent with prior literature. Using standard and novel metrics of lateralization, we were able to significantly differentiate between all doses. Lastly, we demonstrate that these metrics are not only related to behavioral performance during inhibitory control, but also provide complementary information to the legal gold standard of intoxication (i.e. BAC).

Time-Domain Diffuse Optical Tomography for Precision Neuroscience

“…We previously published on the characterization and validation of our prototype system, Kernel Flow1 ( 14 ). While the prototype system was used in several scientific studies ( 13, 15, 16 ), it had some limitations: there were gaps in spatial coverage over the head; pre-recorded instrument response functions (IRFs) were not sufficiently stable in time to ensure accuracy of absolute metrics; detectors had limited sensitivity; and the system had high power requirements. As such, we had confined our prior analyses to those performed in channel space and did not fully explore Flow1’s whole-head DOT capabilities.…”