Assessing Motivational Biases in Brain and Behavior: Event-Related Potential and Response Time Concomitants of the Approach-Avoidance Task

The Approach-Avoidance Task (AAT) is designed to 1) measure the implicit motivated action biases that are instantiated by emotional stimuli, and 2) assess the changes in such biases that drive psychiatric disorder. To establish AAT sensitivity to emotional action bias at a neural level, some work has measured event-related potential (ERP) correlates — however, a lack of research with unpleasant, pleasant, and neutral stimuli together and also a common focus on psychiatric disorder-matched (rather than generally evocative) content limits foundational conclusions that can be drawn. In current research, then, 38 subjects completed an AAT where normative (rather than idiosyncratic) unpleasant, pleasant, and neutral images were shown with a color border indicating if a joystick should be rapidly pushed or pulled to decrease or increase image size. Using generally arousing stimuli, response times (RTs) were found to be faster on unpleasant push compared to unpleasant pull trials, t(37)=2.4, p=.02, and 32-sensor electroencephalography (EEG) also revealed that amplitude of a stimulus-response conflict-related ERP – the N200 – was reduced on unpleasant compared to neutral push trials and un-pleasant push compared to unpleasant pull trials, t(32)=5.5, p<.001. In addition, preliminary exploration of individual differences suggested that relevant variables of dimensional trait anxiety, depression, and anxiety disorder treatment seeking status did not impact RT- or N200-indicated emotional biases. Together, then, findings are consistent with a neurobehavioral avoidance bias for unpleasant stimuli while also suggesting a need to further test whether selecting images for idiosyncratic relevance is critical to revealing individual variations in emotional bias.