Whereas the above studies thus tried to dissociate influences of reward and attention largely during target discrimination processes, the possible dissociations of attention and reward-prospect during task preparation have received little attention so far. Yet, effective preparatory brain mechanisms can be crucial for successful task performance. Moreover, it has been suggested that the dopaminergic system plays an important role in improving task performance mostly in pro-active/preparatory contexts (Braver et al., 2007). Importantly, the dopaminergic response that is typically related to reward anticipation is usually assumed to be only elicited by extrinsic factors (but see Salamone and Correa, 2012). However, in a recent paper by our group (Boehler et al., 2011) this idea was challenged. In this fMRI study, a visual discrimination task was performed in which a cue informed participants of the task demands (high or low) for the upcoming trial. Despite the absence of reward or any other immediate extrinsic motivator, the dopaminergic midbrain showed enhanced activity for high compared to low task demands. Thus, anticipation of attentionally demanding tasks, independent of any extrinsic factor, can invoke neural processes
