Introduction
CORTEX
Decision-making is governed by multiple systems, including the fundamental Pavlovian and instrumental systems. The Pavlovian system involves a pre-preprogrammed behavioral tendency known as Pavlovian bias (i.e., approaching reward-predictive stimuli and avoiding punishment-predictive stimuli) [The neural mechanisms that underlie Pavlovian bias are not fully understood, but some previous research has suggested that the prefrontal cortex plays a pivotal role in overcoming Pavlovian bias [We speculated that the dorsolateral prefrontal cortex (dlPFC) might be a key region involved in controlling Pavlovian bias. The dlPFC has been implicated in higher-level cognitive control and goal-directed actions [In the present study, we evaluated the presence of a causal relationship between the dlPFC and Pavlovian bias using non-invasive brain stimulation (i.e., transcranial direct current stimulation [tDCS]). Using tDCS was based on several previous studies of modulating decision-making biases. For example, the competition between the model-based and the model-free systems [Overall, we investigated whether anodal tDCS on dlPFC would suppress the Pavlovian bias (sham-controlled); we sought to identify the causal neural mechanism underlying such bias. We applied anodal tDCS over the right dlPFC [