Most work on behavior in the fields of Psychology, Economics and Neuroscience claims that people tend to use as little cognitive effort as they can get away with. However, research shows that rewards can be used to boost the amount of cognitive effort used. Currently, theories say that when deciding on the amount of cognitive effort one invests in an activity, this choice is partially based on the reward outweighing the cognitive toil. From a perspective of individual differences, the authors looked into the question of if a person’s ability of executive function is predictive of the degree to which a reward can offset the effort put into to changing tasks. This paradigm of changing tasks was measured with a Stroop test, thus listing further amounts of cognitive endeavors. The results are in line with cost-benefit hypotheses, showing that when executive function was at lower levels, rewards in the form of money were more likely to make the person work harder cognitively. These participants were not up for putting in much cognitive effort, as determined using Need for Cognition. On the other hand, participants with higher levels of executive function, with more innate inclinations to work hard cognitively, were more unmoved by the enticement of a reward. The results of this study point towards the idea that a person’s cost-benefit give and take is curbed by how much they have to give cognitively.