Picture this: it’s the day after New Year’s and you’ve sworn off sweets. You tell everyone that this year is different; you have self-control! And then, two days later, you’re invited to a friend’s birthday party. Not only does she have chocolate fondue, but a whole dessert table loaded with all sorts of sugary goodness! And just like that, you’ve lost all restraint. Wiping smears of chocolate off your face, you are filled with regret and confusion. You were so sure of yourself just a few days ago. What happened? The answer lies within the body’s dopamine system. 

There are two parts of your brain that produce dopamine: the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNc) (Haber, 2014). 

Dopamine is the brain’s way of indicating that you really want something, with the object of desire being referred to as the motivational value. When you encounter things like food, sex, or drugs, the VTA and SNc release dopamine to compel you to pursue it, even if the desire is not healthy or vital to your survival.

Researchers in the field of learning and memory have been tasked with predicting real-life self control from brain activity. Many studies in this field take place in highly controlled lab settings, which begs the question: is any of this ecologically valid? To answer this question, Klaus-Martin Kronke and his colleagues, specializing in neuroscience at the Technical University Dresden in Germany (2019), combined functional MRI readings and smartphone-based assessments to assess how biology factors into self-control. The study was done as part of corresponding author Dr. Thomas Goschke’s lab researching cognitive control and volition (Volition and Cognitive Control, n.d.).

During the quantitative lab portion of the study, participants were shown scenarios that evoked conflict between anticipated short or long-term consequences, such as drinking alcohol or preparing for an exam. Participants were then asked to rate the consequences of these choices on a scale from very positive to very negative. For the qualitative self-control portion of the study, participants filled out questionnaires on their smartphone asking if they had experienced a desire in the past hour, and how strong that desire was. They also indicated whether this desire was in conflict with an overarching goal of theirs (think back to the New Year’s resolution scenario from the beginning of this article). Finally, they were asked if they gave into their desire. 

Results showed that those who had a tendency to make impulsive decisions and lack self-control, both in and out of the lab, were correlated with less neural signaling in the ventromedial prefrontal cortex in response to anticipated long-term consequences. The ventromedial prefrontal cortex is connected to and receives input from the VTA and SNc. 

The implications of this research extend past chocolate. The temptation to smoke, gamble, and other impulses, the thrill that these activities can cause, in the moment, makes you disregard serious long-term consequences, such as lung cancer and financial insecurity.

Next time you find yourself feeling conflicted between sticking to your New Year’s resolutions and giving into your desires, blame those pesky dopamine neurotransmitters.

References

[1] CRC 940: Volition and Cognitive Control. TU Dresden. (2022, February 1). Retrieved July 7, 2022, from https://tu-dresden.de/bereichsuebergreifendes/sfb940

[2] Haber SN. The place of dopamine in the cortico-basal ganglia circuit. Neuroscience. 2014 Dec 12;282:248-57. doi: 10.1016/j.neuroscience.2014.10.008. Epub 2014 Oct 19. PMID: 25445194; PMCID: PMC5484174.

[3] Krönke, KM., Mohr, H., Wolff, M. et al. Real-Life Self-Control is Predicted by Parietal Activity During Preference Decision Making: A Brain Decoding Analysis. Cogn Affect Behav Neurosci 21, 936–947 (2021). https://doi.org/10.3758/s13415-021-00913-w