ABSTRACT
We investigated the neural signatures of expert decision making in the context of police training in a virtual reality-based shoot/don't shoot scenario. Police officers can use stopping force against a perpetrator, which may require using a firearm and each decision made by an officer to discharge their firearm or not has substantial implications. Therefore it is important to understand the cognitive and underlying neurophysiological processes that lead to such a decision. We used virtual reality-based simulations to elicit ecologically valid behaviour from Authorised Firearms Officers (AFOs) in the UK and matched novices in a Shoot/Don't Shoot task and recorded electroencephalography concurrently. We found that AFOs had consistently faster response times than novices, suggesting our task was sensitive to their expertise. To investigate differences in decision making processes under varying levels of threat and expertise, we analysed electrophysiological signals originating from the anterior cingulate cortex. In line with similar response inhibition tasks, we found greater increases in pre-response theta power when participants inhibited the response to shoot when under no threat as compared to shooting. Most importantly, we showed that when preparing against threat, theta power increase was greater for experts than novices, suggesting that differences in performance between experts and novices are due to their greater orientation towards threat. Additionally, shorter beta-rebounds suggest that experts were "ready for action" sooner. More generally, we demonstrate that investigation of expert decision making should incorporate naturalistic stimuli and an appropriate control group to enhance validity.Significance statement This study aims to unravel the complexities of how expertise affects neural processes during uncertain scenarios by investigating police decision making. We present our variant on shoot/don't shoot tasks which was co-developed with police instructors to allow graded levels of force to elicit realistic responses. We show that experts exhibit superior performance in this virtual reality-based task and that this is associated with greater modulation of frontal midline theta activity prior to a decision. Understanding the intricacies of police decision making-especially concerning the use of firearms-is vital to inform policy effectively. Further, the naturalistic imaging methods employed here hold broader significance for neuroscientists aiming to investigate real world behaviour.
