There has been a lot of research into how self-control (defined as “restraint exercised over one’s own impulses, emotions and desires” Merriam-Webster, 2015) is affected by performing tasks that require self-control. One hypothesis with a large amount of experimental evidence to support it is the strength model of self-control (Baumeister, Bratslavsky, Muraven, & Tice, 1998; Baumeister, Vohs, & Tice, 2007). This holds that people’s self-control is a limited resource and that once used up, people will be less able to exert self-control later and will therefore be less likely to restrain themselves (Hagger, Wood, Stiff, & Chatzisarantis, 2010). This loss of your self-control resource is called “ego depletion”. Believing this then supposedly allows you to allocate you resources more efficiently and thus improve self-regulation (Vohs, Baumeister, & Schmeichel, 2012).

However there have been several studies that suggest ego depletion itself is not the cause of reduced self-control at a later time; it’s the person’s beliefs about whether their self-control resources is depleted or not that results in lapses of self-control (Job, Dweck, & Walton, 2010). So it’s not that your self-control resources is actually depleted; it’s that you believe they have and you will therefore be less likely to put in the effort required to maintain self-control. This is contrasted with those who believe in a nonlimited theory of willpower who do not experience a decrease in self-control across demanding tasks (Miller, Walton, Dweck, Job, Trzesniewski, & McClure, 2012).

A study by Job, Walton, Bernecker, & Dweck (2015) looked at the effect different beliefs about willpower had on everyday self-regulation (e.g.procrastination, consumption of unhealthy foods, poor time management, excess spending, and failure to control emotions). The participants had to say when they had experienced “self-regulation failures” in the past week. The data was therefore based on self-report, which comes with a host of problems (social desirability bias, lying), some time after the event occurred (so the participants may have forgotten). They were also  required to predict how many demands they would face in the coming week (academic tasks e.g. “tests to take”, and social stressors e.g. “experience of social exclusion”). Their natural self-control ability was also calculated (through a questionnaire).

They found no significant difference in anticipated demands between students with different theories about willpower. When students experienced/reported high demand, those with a limited resource-theory reported a greater number of self-regulation failures on procrastination. The other measures either didn’t reach significance or only just reached it (so I’m not going to focus on those). There was no significant difference between theories of willpower when demands were low. The possibility that students who endorsed the limited resource-theory were simply worse at self-regulating behaviour was controlled for and they still found a significant effect of different theories of willpower on self-regulatory failures (during high demand). This implies their beliefs about willpower affected their reported self-regulatory failures, as opposed to their natural ability to control themselves being the only causal factor.

The next step was examining whether beliefs about willpower affected an objective measure (in this case, GPA or grade point average for us non-Americans). Even when controlling for prior GPA, the students who agreed with the limited resource-theory scored lower on their GPA (though this variable only just reached significance). They also found that students who believed in the limited resource theory (and were on a course with a high work-load) scored significantly lower GPA’s than students who endorsed a nonlimited view of willpower on the same course (this last result was found even when the participant’s natural self-control was controlled for).

This is an interesting study as it suggests students who hold willpower is a limited resource are more likely to procrastinate and thus achieve a lower grade in their final tests. I feel running this as a longitudinal study and using better methods of recording self-regulatory failures would be a good next step.

References:
Baumeister, R.F.; Bratslavsky, E.; Muraven, M.; & Tice, D.M. (1998). Ego Depletion: Is the Active Self a Limited Resource? Journal of Personality and Social Psychology, 74 (5), 1252-1265.
Baumeister, R.F.; Vohs, K.D.; & Tice, D.M. (2007). The Strength Model of Self-Control. Current Directions in Psychological Science, 16 (6), 351-355.
Hagger, M.S.; Stiff, C.; & Chatzisarantis, N.L.D. (2010). Ego Depletion and the Strength Model of Self-Control: A Meta-Analysis. Psychological Bulletin, 136 (4), 495-525.
Job, V.; Dweck, C.S.; & Walton, G.M. (2010). Ego Depletion- Is It All In Your Head? Implicit Theories About Will-Power Affect Self-Regulation. Psychological Science, 21 (11), 1686-1693.
Job, V.; Walton, G.M.; Bernecker, K.; & Dweck, C.S. (2015). Implicit Theories About Willpower Predict Self-Regulation and Grades in Everyday Life. Journal of Personality and Social Psychology, 108 (4), 637-647.
Merriam-Webster. (2015). Self-control. Available at: http://www.merriam-webster.com/dictionary/self-control. Last accessed 07/04/2015.
Miller, E.M.; Walton, G.M.; Dweck, C.S.; Job, V.; Trzesniewski, K.H.; & McClure, S.M. (2012). Theories of Willpower Affect Sustained Learning. PLoS ONE, 7 (6), e38680, doi:10.1371/journal.pone.0038680.
Vohs, K.D.; Baumeister, R.F.; & Schmeichel, B.J. (2012). Motivation, personal beliefs, and limited resources all contribute to self-control. Journal of Experimental Social Psychology, 48 (4), 943-947. (function(i,s,o,g,r,a,m){i[‘GoogleAnalyticsObject’]=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,’script’,’//www.google-analytics.com/analytics.js’,’ga’); ga(‘create’, ‘UA-63654510-1’, ‘auto’); ga(‘send’, ‘pageview’);