Behavioral and neural correlates of increased self-control in the absence of increased willpower

People often exert willpower to choose a more valuable delayed reward over a less valuable immediate reward, but using willpower is taxing and frequently fails. In this research, we demonstrate the ability to enhance self-control (i.e., forgoing smaller immediate rewards in favor of larger delayed rewards) without exerting additional willpower. Using behavioral and neuroimaging data, we show that a reframing of rewards (i) reduced the subjective value of smaller immediate rewards relative to larger delayed rewards, (ii) increased the likelihood of choosing the larger delayed rewards when choosing between two real monetary rewards, (iii) reduced the brain reward responses to immediate rewards in the dorsal and ventral striatum, and (iv) reduced brain activity in the dorsolateral prefrontal cortex (a correlate of willpower) when participants chose the same larger later rewards across the two choice frames. We conclude that reframing can promote self-control while avoiding the need for additional willpower expenditure.Self-control is highly desirable and correlates with beneficial outcomes such as financial stability (1, 2), academic achievement (3, 4), social success (5, 6), and healthy living (1, 7). Many cognitive and behavioral strategies may be used to achieve self-control (8). We contrast two broad self-control strategies that affect how people respond to an immediately available, tempting reward. First, people may attempt to directly modulate their behavior through effortful willpower exertion, to select delayed rewards despite the presence of distracters or temptations. Alternatively, the perception of temptations may be altered so as to promote self-control. Exerting willpower is taxing and hence often of limited efficacy (9). By contrast, changing how outcomes are perceived and valued has the benefit of more automatically shaping behavior and may prove a superior target for interventions and long-term behavioral change.Recent findings support the plausibility of independently assessing changes in reward valuation and changes in willpower exertion because brain systems underlying reward valuation are distinct from those associated with willpower exertion (10, 11). More specifically, studies of intertemporal choice link valuation processes to the ventromedial prefrontal cortex and striatum (10, 12–14), whereas willpower exertion is associated with the dorsolateral prefrontal cortex (dlPFC) (10, 11, 15). However, no study has demonstrated that self-control can be engaged in a way that influences monetary choice behavior in an intertemporal choice context without the exertion of additional willpower.Our goal was to demonstrate that the ability to make far-sighted choices may be enhanced without requiring the use of additional willpower, by altering how rewards are perceived and valued. We triangulated the process of altering reward perception and valuation by obtaining data through self-report (subjective reward valuation), behavioral measures (monetary choices), and neuroimaging (neural activity underlying reward valuation versus willpower exertion). In doing so, we capitalized on the hidden-zero effect, a subtle cognitive framing manipulation (16) that increases selection of larger delayed monetary rewards over smaller immediate monetary rewards.In our paradigm, instead of presenting choices in a traditional hidden-zero format (e.g., “Would you prefer [A] $5 today OR [B] $10 in a month?”), choices are presented in an explicit-zero format, which references the nonreward consequences of each choice (e.g., “Would you prefer [A] $5 today and $0 in a month OR [B] $0 today and $10 in a month?”). Including future outcomes in all choice options has been argued to reduce the attentional bias toward immediate rewards that contributes to impulsive behavior (17).Of course, this change in attention may influence reward evaluation (by making the delayed reward more valued relative to the immediate one), or it may prompt greater effortful exertion of willpower. In terms of the latter possibility, willpower has been argued to arise from conflict in the decision process (11), and increased attention to future rewards (or nonrewards) may enhance conflict with a desire for immediate gratification. In this case, an effortful process might be triggered. We tested these two alternatives for the basis of the hidden-zero effect. In study 1, we examined the effect of the explicit-zero framing on participants’ subjective valuation of immediate and delayed rewards and linked this effect to monetary choice. In study 2, we used functional magnetic resonance imaging (fMRI) to identify the neural effects of reframing on reward valuation, monetary choice behavior, and willpower exertion.