ABSTRACT
Recent analyses of goal-directed action have not only pointed to the importance of the learning processes through which actions and their consequences are encoded, but have also emphasized the performance factors that in uence choice between actions and action initiation more generally (Dickinson and Balleine 2002; Hasselmo 2005; Balleine and Ostlund 2007). It is important to understand why this is the case. Although the value of acting-or not acting-can often appear to be obvious enough from an adaptive perspective, in fact the information that can be derived from the action-outcome association is not suf cient to determine a course of action; knowing that an action results in a particular outcome does not entail whether that action should be performed or not. Although it might appear adaptive to perform food-related actions more frequently when food deprived and less frequently when replete, this need not necessarily occur and often doesn’t, something well documented in cases of eating disorders (Davis et al. 2004; Morrison and Berthoud 2007). In fact, what determines whether a speci c action will be both selected and subsequently initiated is not just the identity but also the evaluation of the outcome associated with the selected action.
