Cover Image by Steve DiMatteo from Pixabay

By Althea Kaminske

Thinking is hard. As someone whose career is more or less based on thinking thoughts, and communicating those thoughts effectively, I have a love-hate relationship with thinking. There are days when I’m excited to work through tough problems and read interesting and relevant research. Most days I’m genuinely excited to talk about those things with other people. There are even days when I delight in writing about those things. But, there are also a lot of days when I am exhausted and overwhelmed and might cry if asked to think one more thought. When I have no more opinions to give. No more thoughts on the topic. No ideas about what to have for dinner. According to a recent meta-analysis - “The unpleasantness of thinking: A meta-analytic review of the association between mental effort and negative affect” (1) - I am not alone.

There is a long history of research in psychology that suggests that people, and animals, generally do not like to do more than is necessary. This has been called the “law of less work” (2) or the “law of minimum effort” (3). These “laws” followed from research on animal behavior in the 1930s and 40s that found that animals will generally try to expend as little effort as possible when given the choice. Later research on human reasoning and decision making found that people tend to adopt heuristics as opposed to algorithms. Heuristics are simple, and therefore easier, processes that yield correct results most of the time, while algorithms are complex, and therefore more effortful, processes that yield correct results all of the time (4). We also tend to only exert mental effort when we think the rewards are attainable and sufficiently valuable (5). When presented with choices that require different amounts of effort, there are a variety of factors that influence whether or not we’ll choose to do something that requires more effort. Sleep, fatigue, and information about the reward all impact our choice (1). All of these findings support the idea that cognitive effort (i.e. “thinking”) is resource-intensive and we like to conserve our resources. 

Thinking is effortful, but is it unpleasant? Here the evidence is somewhat mixed. On the one hand, we tend to require rewards to pursue more effortful thinking which suggests that the effort of thinking may not be rewarding in and of itself. On the other hand, research on the “need for cognition” suggests that there is variation in how people seek out and engage with cognitive activities. Research in this area has found that people who score higher in “need for cognition” tend to rate cognitive tasks as more enjoyable (6).

To better understand the relationship between mental effort and negative affect, David, Vassena, and Bijleveld conducted a meta-analysis of 170 studies of mental effort (1). They looked at a number of moderators to see what factors have an effect on this relationship. Does education level matter? Maybe people who have attained a higher degree of education have a higher need for cognition and don’t find it unpleasant. Does experience or skill matter? Maybe people have learned to enjoy effortful tasks over time. Does feedback matter? Many tasks have been “gamified” such that you can monitor your progress or points on a task to make it more like leveling up in a game. Maybe that makes demanding tasks more enjoyable. In total the authors looked at 15 different moderators. 

Somewhat surprisingly, of the 15 different moderators only one had a significant effect: whether the study was conducted in Asia or in North America/Europe. Nothing else mattered. Not education level, not experience, not even gamification. Across all of the studies they found a strong relationship between mental effort and negative affect: on average, for every point increase in effort there was a .85 increase in negative affect (1). We really don’t like thinking. However, that effort was perceived as more unpleasant by people in North American or European countries than in Asian countries. The interpretation of this result highlights some of the complexities of cultural psychology. It could be that exposure to mental effort and the value placed on that mental effort are different in Asian countries compared to North American and European countries. For example, the authors highlight the hours that high school students spend on school work in China and the prevalence of cram schools in Japan. It is also possible that words like “effort” and “annoyed” have different connotations when translated into those languages which influenced survey responses (all studies included in the meta-analysis used the same survey to measure mental effort, including translated versions). However, while the size of the effect is somewhat smaller in Asian countries, people still found mental effort to be aversive.

I think that understanding that thinking in general, let alone thinking critically and learning, is resource-demanding is also useful for reframing conversations around education. I’ve written previously about the impact of providing breakfast and lunch at schools. Our brains require energy to think with around 20% of our calories going towards the brain (7), and cognitive tasks that are more demanding burn more calories (8). We see students drifting off or falling asleep in class and might assume that they are unengaged or unmotivated. While motivation and engagement certainly play a role in how a student shows up for class, it is also worth asking whether that student is eating or sleeping enough to get them through a cognitively demanding day.

I also think recognizing that thinking is hard and resource demanding may help to address some of the shame and stigma high-achieving students feel when they encounter academic difficulties. Anecdotally, one of the common questions I get from medical students is how long they should be able to study before needing a break. Four hours? Five? Of course, the answer is that there are lots of factors. Your overall mental and physical health affects your ability to think. If you’ve been sleeping, eating, and exercising well then you’ll likely find that you’re able to study for longer and more productively. If you’re tired or unwell then you’ll get fatigued more easily and will need more breaks. Without proper rest and resources your motivation and ability as a student will only get you so far. Thinking is hard and needing breaks to refuel and re-energize is normal. 

Thinking is hard. And yet we still do it. Why? One of my favorite topics to talk about is critical thinking. My favorite book to teach out of is Thought and Knowledge by Diane Halpern (9). One of the themes throughout the book is that critical thinking is as much a disposition, or a willingness to engage and put forth effort, as it is a set of cognitive skills. I get frustrated by the assumption that emotion must be removed from logic. That being emotional somehow is separate or different from being rational. As if it is possible to remove all bias by removing all feelings. What this research, and research on critical thinking, suggests to me is that the reason why we keep thinking, and thinking critically, is because we care. We don’t do it because it’s easy. We do it because we care about something. Because we care about people, the environment, and the world around us. We care enough to push through the unpleasantness of thinking so that we can solve problems, make connections, and support people around us.

References

1. David, L., Vassena, E., & Bijleveld, E. (2024). The unpleasantness of thinking: A meta-analytic review of the association between mental effort and negative affect, Psychological Bulletin, 1-24. https://doi.org/10.1037/bul0000443 

2. Hull, C. L., (1943). Principles of behavior: An introduction to behavior theory. Appleton-Century

3. Tsai, L. S. (1932). The laws of minimum effort and maximum satisfaction in animal behavior. The National Institute of Psychology. 

4. Tversky, A., & Khaneman, D. (1974). Judgment under uncertainty: Heuristics and biases, Science, 185(4157), 1124-1131. https://doi.org/10.1126/science.185.4157.1124 

5. Richter, M. Gendolla, G. H., E., & Wright, R. A. (2016). Three decades of research on motivational intensity theory: What we have learned and what we still don’t know. In A. J. Elliott (Ed.), Advances in motivation science (Vol. 3, pp. 149-186). Elsevier. https://doi.org/10.1016/bs.adms.2016.02.001 

6. Cacioppo, J. T., Petty, R. E., Feinstein, J. A., & Jarvis, W. B. G. (1996). Dispositional differences in cognitive motivation: The life and times of individuals varying in need for cognition. Psychological Bulletin, 119(2), 197-253. https://doi.org/10.1037/0033-2909.119.2.197 

7. Scholey, A.B., Harper, S., & Kennedy, D. O. (2001). Cognitive demand and blood glucose. Physiology & Behavior, 73(4), 585-592. https://doi.org/10.1016/s0031-9384(01)00476-0 

8. Larson, G. E., Haier, R. J., LaCasse, L., & Hazen, K. (1995). Evaluation of a “mental effort” hypothesis for correlations between cortical metabolism and intelligence. Intelligence, 21(3), 267-278. https://doi.org/10.1016/0160-2896(95)90017-9 

9. Halpern, D. F. (2014). Thought and knowledge: An introduction to critical thinking (5th ed.). Psychology Press.