Article révisé par les pairs
Résumé : In their daily decisions, humans and animals are often confronted with the conflicting choice of opting either for a rewarding familiar option (i.e., exploitation) or for a novel, uncertain option that may, however, yield a better reward in the near future (i.e., exploration). Despite extensive research, the cognitive mechanisms that subtend the manner in which humans solve this exploration-exploitation dilemma are still poorly understood. In this study, we challenge the popular assumption that exploitation is a global default strategy that must be suppressed by means of cognitive control mechanisms so as to enable exploratory strategies. To do so, we asked participants to engage in a challenging working memory task while performing repeated choices in a gambling task. Results showed that manipulating cognitive control resources exclusively hindered participants' ability to explore the environment in a directed, intentional manner. Moreover, under certain scenarios, adopting exploitative strategies was also dependent on the availability of cognitive control resources. Additional analyses using a recent computational model of information integration suggests that increasing cognitive load specifically interferes with the ability to combine reward and information in order to inform choices. Our results shed light on the cognitive mechanisms that underpin the resolution of the dilemma and provide a formal foundation through which to explore pathologies of goal-directed behavior.