Reward Influence on the Heart: Cardiovascular Response as a Function of Incentive Value at Five Levels of Task Demand

This study examined cardiovascular effects of incentive value in men and women confronted with cognitive challenges that were more and less difficult to meet. Participants performed computer memory tasks varying in difficulty from low to high, with instructions that they could earn chances toward a $100 prize or $10 prize by attaining a 90% success rate. Analysis of cardiovascular responses assessed during work revealed an interaction between difficulty and incentive value for heart rate. Participants' heart rate responses were proportional to task difficulty and unaffected by incentive value in all conditions except for the most difficult one. Where difficulty was greatest, $100 participants showed relatively high heart rate responsiveness, whereas $10 participants showed low heart rate responsiveness. This heart rate finding corroborates and extends cardiovascular results from previous experiments, and lends further support to the view that cardiovascular responses will be proportional to incentive value only under some task conditions.