Subsequent to the preparation phase, the early perceptual processing of the target was not affected by the reward or difficulty manipulation, which is consistent earlier reports (Baines et al., 2011; Hughes et al., 2012) could not find an early reward impact in the target P1-N1 component in their cueing paradigms. The earliest manipulation effects in the current study were observed 200 ms after target onset. In particular, the P2 amplitude was largest for low-difficulty reward trials and for the N2 and the P3 component a main effect of reward was observed, with an enhanced positive wave for reward trials. These findings match with the results of several recent ERP studies investigating reward, suggesting that attention to or attentional capture by rewarding or affective stimuli was increased (e.g., Baines et al., 2011; Hajcak et al., 2010; Hughes et al., 2012; Krebs et al., 2013). The amplitude of the P3 in the present study was also larger in the low-difficulty condition compared to the high-difficulty condition, perhaps due to reward expectancy being higher in the low-difficulty trials (Goldstein et al., 2006; Gruber
