Make everything as simple as possible, but not simpler.
— Albert Einstein
When faced with either working on math problems to prepare for an upcoming test or texting with friends, why does one student (Mat) choose to work on the math problems, while another student (Tex) chooses to text with his friends? Kurzban et al.'s model provides a simple framework for these decisions: The expected utilities of the two activities as estimated by Mat and Tex differ. Mat chooses to study because he values doing the math problems more than texting. And Tex chooses to text because he associates higher value to texting than to studying. Moreover, according to the authors, if Tex were to work on math problems, he would experience fatigue because of the greater expected utility he assigns to texting, and this subjective experience is likely to disengage him from studying.
Despite the appeal of the simplicity of the Kurzban et al. framework, we argue that important information is lost in their simplification. One unifying theme in research on self-regulation and delay of gratification (e.g., Mischel et al. Reference Mischel, Ayduk, Berman, Casey, Jonides, Kross, Wilson, Zayas and Shoda2011; Zayas et al., in press), which is largely unaddressed by Kurzban et al., has implications for the factors that influence how people assign value to rewards and costs of various behavioral options. Why does Mat assign a higher utility to studying (vs. texting), compared to Tex? Below we summarize research that identifies key situational and psychological factors that affect how people represent rewards and costs in each behavioral option, and how these, in turn, naturally influence whether people persist on difficult tasks.
All situations are not equal: Situations involving immediate versus delayed outcomes
Does a person study now for a reward to-be-obtained in the future, or instead chat with friends on the phone? This situation reflects a typical delay of gratification dilemma, which involves forgoing an immediately available reward for the sake of a more desirable reward in the future. Surprisingly, Kurzban et al. provide little discussion of how inherent, structural differences in these competing situations affect how they are construed and ultimately which tasks individuals pursue. As we discuss next, situational and psychological factors likely influence the estimation of rewards and costs, and thus the activities to which one decides to allocate computational resources.
Immediate/concrete outcomes loom larger than distal/abstract outcomes
Differences in the temporal nature of the competing situations (delayed vs. immediate) affect a person's estimates of the costs and rewards. In situations discussed by Kurzban et al., the rewards of the current activity (doing math) are delayed but its costs are immediate. In contrast, in situations involving a tempting alternative (texting), the rewards are immediate but its costs are delayed. All things being equal, immediately available rewards weigh more than rewards accrued sometime in the future, and likewise, the costs in an immediate situation weigh more than costs in a delayed situation (e.g., Ainslie Reference Ainslie1975). Hence, differences in the temporal nature of the competing situations affect the expected utilities of the current and alternative activities, thereby favoring the allocation of resources toward situations in which the rewards are immediately available.
Reflexively responding to the immediate and reflectively conjuring the future
The competing situations (immediate vs. delayed) in a delay of gratification dilemma also differ in their inherent difficulty. First, the activities themselves differ on the effortful versus automatic dimension. In situations involving immediately available rewards, obtaining the rewards is typically achieved relatively effortlessly. Mindlessly texting simply requires engaging in more reflexive and automatic processes (e.g., Hofmann et al. Reference Hofmann, Friese and Strack2009). In contrast, in situations involving delayed rewards, obtaining the rewards is typically associated with greater effort. Working on math problems to earn good grades in the future presumably requires effortful and more reflective processes.
A second difference in the inherent difficulty of the two competing situations emerges in how the goals are represented. Whereas immediate outcomes are readily available and easily processed, delayed outcomes must be envisioned. Indeed, individuals must keep the delayed rewards in mind, albeit not necessarily consciously, to continue working toward the goal and simultaneously inhibit tempting, highly accessible alternative representations (e.g., Hofmann et al. Reference Hofmann, Schmeichel and Baddeley2012). The ability to control the content of working memory is a key ability in cognitive control and facilitates delay of gratification (Berman et al. Reference Berman, Yourganov, Askren, Ayduk, Casey, Gotlib, Kross, McIntosh, Strother, Wilson, Zayas, Mischel, Shoda and Jonides2013; Casey et al. Reference Casey, Somerville, Gotlib, Ayduk, Franklin, Askren, Jonides, Berman, Wilson, Teslovich, Glover, Zayas, Mischel and Shoda2011; Eigsti et al. Reference Eigsti, Zayas, Mischel, Shoda, Ayduk, Dadlani, Davidson, Lawrence Aber and Casey2006).
Thus, situations that differ in the immediacy (vs. delay) of the rewards and costs possess another inherent asymmetry: All things being equal, the computational costs in a situation involving delayed rewards are higher than those in which the rewards are immediately available.
Representations of future rewards affect expected utilities
Given the structural reasons why delaying gratification is difficult (as described above), not surprisingly considerable research has shown that being able to control mental representations of various behavioral options and associated outcomes is a key factor influencing whether one persists in working on a difficult task (for a review, see Zayas et al., in press). For example, being able to bring to mind goal-relevant representations, keep them active in working memory, and shield them from competing goals lessens tempting aspects of the situation and facilitates persistence on difficult tasks (Fujita Reference Fujita2011). In some situations, representing delayed goals may increase the salience of future rewards (in a sense it makes them more immediate), and increase motivation. However, in some cases, focusing on delayed rewards may be detrimental (see Metcalfe & Mischel Reference Metcalfe and Mischel1999).
Moreover, keeping a delayed reward in mind may even affect the mental effort of pursuing the current mental activity. When the value of the future reward (obtaining a good grade) increases relative to the value of the alternative option (texting), pursuing the current activity may require less effort and less executive functions to inhibit the tempting alternative (in a sense, temptations are no longer as salient and alluring; Ferguson Reference Ferguson2008).
In sum, why does Mat choose to study for his math test whereas Tex chooses to text with his friends instead? The fact that one values texting more than studying is fairly self-evident. The important question is why does one student value texting more than studying. To provide a comprehensive framework of self-regulation that accounts for these individual differences and situational factors, Kurzban et al.'s model should incorporate psychological processes that affect representations of costs and rewards.
Make everything as simple as possible, but not simpler.
— Albert EinsteinWhen faced with either working on math problems to prepare for an upcoming test or texting with friends, why does one student (Mat) choose to work on the math problems, while another student (Tex) chooses to text with his friends? Kurzban et al.'s model provides a simple framework for these decisions: The expected utilities of the two activities as estimated by Mat and Tex differ. Mat chooses to study because he values doing the math problems more than texting. And Tex chooses to text because he associates higher value to texting than to studying. Moreover, according to the authors, if Tex were to work on math problems, he would experience fatigue because of the greater expected utility he assigns to texting, and this subjective experience is likely to disengage him from studying.
Despite the appeal of the simplicity of the Kurzban et al. framework, we argue that important information is lost in their simplification. One unifying theme in research on self-regulation and delay of gratification (e.g., Mischel et al. Reference Mischel, Ayduk, Berman, Casey, Jonides, Kross, Wilson, Zayas and Shoda2011; Zayas et al., in press), which is largely unaddressed by Kurzban et al., has implications for the factors that influence how people assign value to rewards and costs of various behavioral options. Why does Mat assign a higher utility to studying (vs. texting), compared to Tex? Below we summarize research that identifies key situational and psychological factors that affect how people represent rewards and costs in each behavioral option, and how these, in turn, naturally influence whether people persist on difficult tasks.
All situations are not equal: Situations involving immediate versus delayed outcomes
Does a person study now for a reward to-be-obtained in the future, or instead chat with friends on the phone? This situation reflects a typical delay of gratification dilemma, which involves forgoing an immediately available reward for the sake of a more desirable reward in the future. Surprisingly, Kurzban et al. provide little discussion of how inherent, structural differences in these competing situations affect how they are construed and ultimately which tasks individuals pursue. As we discuss next, situational and psychological factors likely influence the estimation of rewards and costs, and thus the activities to which one decides to allocate computational resources.
Immediate/concrete outcomes loom larger than distal/abstract outcomes
Differences in the temporal nature of the competing situations (delayed vs. immediate) affect a person's estimates of the costs and rewards. In situations discussed by Kurzban et al., the rewards of the current activity (doing math) are delayed but its costs are immediate. In contrast, in situations involving a tempting alternative (texting), the rewards are immediate but its costs are delayed. All things being equal, immediately available rewards weigh more than rewards accrued sometime in the future, and likewise, the costs in an immediate situation weigh more than costs in a delayed situation (e.g., Ainslie Reference Ainslie1975). Hence, differences in the temporal nature of the competing situations affect the expected utilities of the current and alternative activities, thereby favoring the allocation of resources toward situations in which the rewards are immediately available.
Reflexively responding to the immediate and reflectively conjuring the future
The competing situations (immediate vs. delayed) in a delay of gratification dilemma also differ in their inherent difficulty. First, the activities themselves differ on the effortful versus automatic dimension. In situations involving immediately available rewards, obtaining the rewards is typically achieved relatively effortlessly. Mindlessly texting simply requires engaging in more reflexive and automatic processes (e.g., Hofmann et al. Reference Hofmann, Friese and Strack2009). In contrast, in situations involving delayed rewards, obtaining the rewards is typically associated with greater effort. Working on math problems to earn good grades in the future presumably requires effortful and more reflective processes.
A second difference in the inherent difficulty of the two competing situations emerges in how the goals are represented. Whereas immediate outcomes are readily available and easily processed, delayed outcomes must be envisioned. Indeed, individuals must keep the delayed rewards in mind, albeit not necessarily consciously, to continue working toward the goal and simultaneously inhibit tempting, highly accessible alternative representations (e.g., Hofmann et al. Reference Hofmann, Schmeichel and Baddeley2012). The ability to control the content of working memory is a key ability in cognitive control and facilitates delay of gratification (Berman et al. Reference Berman, Yourganov, Askren, Ayduk, Casey, Gotlib, Kross, McIntosh, Strother, Wilson, Zayas, Mischel, Shoda and Jonides2013; Casey et al. Reference Casey, Somerville, Gotlib, Ayduk, Franklin, Askren, Jonides, Berman, Wilson, Teslovich, Glover, Zayas, Mischel and Shoda2011; Eigsti et al. Reference Eigsti, Zayas, Mischel, Shoda, Ayduk, Dadlani, Davidson, Lawrence Aber and Casey2006).
Thus, situations that differ in the immediacy (vs. delay) of the rewards and costs possess another inherent asymmetry: All things being equal, the computational costs in a situation involving delayed rewards are higher than those in which the rewards are immediately available.
Representations of future rewards affect expected utilities
Given the structural reasons why delaying gratification is difficult (as described above), not surprisingly considerable research has shown that being able to control mental representations of various behavioral options and associated outcomes is a key factor influencing whether one persists in working on a difficult task (for a review, see Zayas et al., in press). For example, being able to bring to mind goal-relevant representations, keep them active in working memory, and shield them from competing goals lessens tempting aspects of the situation and facilitates persistence on difficult tasks (Fujita Reference Fujita2011). In some situations, representing delayed goals may increase the salience of future rewards (in a sense it makes them more immediate), and increase motivation. However, in some cases, focusing on delayed rewards may be detrimental (see Metcalfe & Mischel Reference Metcalfe and Mischel1999).
Moreover, keeping a delayed reward in mind may even affect the mental effort of pursuing the current mental activity. When the value of the future reward (obtaining a good grade) increases relative to the value of the alternative option (texting), pursuing the current activity may require less effort and less executive functions to inhibit the tempting alternative (in a sense, temptations are no longer as salient and alluring; Ferguson Reference Ferguson2008).
In sum, why does Mat choose to study for his math test whereas Tex chooses to text with his friends instead? The fact that one values texting more than studying is fairly self-evident. The important question is why does one student value texting more than studying. To provide a comprehensive framework of self-regulation that accounts for these individual differences and situational factors, Kurzban et al.'s model should incorporate psychological processes that affect representations of costs and rewards.