The end of the year brings with it the intimidating prospect of setting new resolutions for 2013. New Year’s resolutions often come up in conversation when I tell people that I study goal pursuit, and their reports are usually fraught with negative emotions ranging from frustration to terror. A surprising number of people I talk to report giving up on making resolutions entirely because of past failures. These common experiences always bring me back to one of my main research questions: Why is successfully sticking to new goals so hard?
A long answer to that question could fill several books*, but there is a short answer that is almost as satisfying. Resolutions by definition involve doing something new or different, which requires moving against the path of least resistance, behaviorally speaking, and humans seem to have a limited capacity to do that. In the parlance of academic psychology, “self-regulation”, the set of motivational and cognitive skills that allow us to act in the service of long-term goals like the ones we set around New Year’s instead of short-term temptations, is powerful but fatigues rapidly with use. When we set out on a new path toward our resolutions, we can travel only so far before we need to take a break, at which point we risk stumbling back into our old routes.
Now here’s where things get really interesting. For the last decade or so, psychologists thought they knew that the cause of the limits on self-regulation was blood glucose. The prevailing model was that self-regulation relied upon brain regions that consumed large amounts of energy (in the form of glucose), and that these regions became depleted when blood glucose levels ran low. But several recent studies have provided evidence that directly contradicts that theory. For example, rinsing one’s mouth with a sweet, glucose-rich drink—without swallowing any of it—repairs self-regulatory function. Even simply believing that a task is depleting (or not) can make it so, irrespective of the actual effort it requires. It seems that the limited resource underlying our ability to move against the path of least resistance is not physiological but rather psychological in nature.
The collapse of the glucose explanation resulted in an explanatory vacuum. Nobody knows why we have a limited ability to pursue long-term goals (or at least why our capacity becomes limited when we think it will), but psychologists have come up with some very cool hypotheses. One is that the deterioration of self-regulation over time evolved as an automatic internal signal of the opportunity costs of focusing on any one hard goal, presumably to the detriment of others. Another is that exerting self-regulation feels like work, so after a while we feel like we’ve earned a break and are therefore “licensed” to redirect our attention and motivation away from our goals and toward more immediate gratifications. Two recurrent themes among the new theories are that subjective perceptions of how much effort was put forth—rather than actual expenditures—are what cause lapses in self-regulation, and that this subjective feeling of effort serves as an mental “regulometer” that helps guide decisions about which goals to work on and which to let slip.
Only a handful of studies have used neuroimaging to understand why self-regulation falters with repeated use, and one particular experiment has uncovered a couple of provocative pieces of data. First, participants who engaged in self-regulation in the first half of the study (compared to those who did not) had more amygdala activation in response to unpleasant stimuli in the second half. On a neural level, these participants became more sensitive to negative stimuli following self-regulation. Second, whereas control participants (who did not expend effort in the first half of the study) showed the normal correlation between amygdala and prefrontal brain regions typically associated with self-regulation, participants who engaged in self-regulation in the first half showed no relationship at all between these two regions. In other words, working hard toward a goal initially causes a subsequent reduction in the usual coupling between regulation and emotion reactivity systems, in this case resulting in increased amygdala activity. This result is consistent with some of the new models I mentioned earlier. Rather than being depleted to the point of exhaustion, it is as though people who had previously used self-regulation simply decided not to use it a little while later, perhaps on an implicit level.
We’re still a long way from a complete understanding of how this all works and why, but for now there is reason to be optimistic if you’ve made a New Year’s resolution. The self-regulation it’ll take for you to achieve your goal might be limited, but not by some inflexible physiological rule. The capacity for self-regulation is always there, you just need to remember to make the choice to use it.