MedicalResearch.com Interview with: Ksenija Marinkovic and Lauren Beaton Psychology Department - College of Sciences Spatio-Temporal Brain Imaging Lab Center for Clinical and Cognitive Neuroscience San Diego State University San Diego CA MedicalResearch.com: What is the background for this study? What are the main findings? Response: In general, we subjectively perceive our actions to be under our deliberate and voluntary control. However, our results are consistent with other accruing evidence suggesting that a large portion of our behavior is automatic and not accessible to conscious experience. The automatic processing primarily underlies predictable daily routines when we seem to be on an “auto-pilot”. In contrast, situations that are ambiguous or that evoke incompatible response tendencies engage cognitive control which allows conscious override of the preplanned actions and results in flexible behavior. Our study used a multimodal imaging approach that combines perfect time sensitivity of magnetoencephalography (MEG) with structural magnetic resonance imaging (MRI) to investigate spatio-temporal stages of the seamless interplay between automatic and controlled processing. MEG is a highly sensitive method that records magnetic fields generated by the brain’s neural activity in real time. Young, healthy, participants performed a version of the Eriksen Flanker task, which presents two colored squares on either side of a centrally presented target square that appears after a short delay. Participants are instructed to press a button corresponding to the color of the target square in the middle and to pay no attention to the flankers. Although participants know that the flankers are irrelevant, they are unable to disregard them deliberately. Instead, flankers trigger an automatic preparation to respond. This is particularly apparent on mismatch trials on which the flanker color is misleading and it activates the wrong hand. Target appearance overrides the initial automatic response as the response plan is switched to the other hand to make a correct response. This process reflects recruitment of cognitive control or the decision-making capacity which includes a range of functions such monitoring contextual demands, selecting the correct response, and suppressing an automatic but irrelevant action. Our multimodal MEG imaging method has allowed us to track the neural response as the brain prepares an incorrect response to flankers and then “switches” motor preparation between hemispheres. This approach makes it possible to investigate the interplay between automatic and controlled processing and dissect decision making as it unfolds. The addition of a moderate dose of alcohol dysregulates this frontal network involved in motor decision making, which decreases accuracy when response conflict is present and lowers neural activity reflecting cognitive control. Related to this overall decrease, and of clinical importance, is the reduced ability to employ cognitive control to refrain from drinking excessively. However, the underlying patterns of response-switching were preserved under alcohol, suggesting that alcohol primarily induces deficits upstream during decision making and not during executing motor commands.