The aim of this study was twofold: first, to examine the influence of decision reinvestment on decision-making performance using an option-generation task, and second to investigate its neurophysiological basis with heart rate variability. Forty-two male participants performed an option-generation task (i.e., where participants are required to generate their own options rather than being asked to decide from a set of options) under low- and high-pressure conditions. Results showed that the decision-making performance of low and high decision reinvesters was similar in the low-pressure condition, however in the high-pressure condition low reinvesters decided faster than their high reinvester counterparts. Moreover, we found that the pressure-induced reduction in parasympathetic activity was more pronounced in high reinvesters in comparison to low reinvesters. Findings are interpreted in light of the neurovisceral integration model, assuming a positive relationship between cognitive performance and parasympathetic activity. These findings offer a physiological insight into a psychological phenomenon and may also suggest a way to counteract the detrimental effects of decision reinvestment by utilizing interventions that target the parasympathetic activity, such as heart rate variability biofeedback.