“The Unpleasantness of Thinking: A Meta-Analytic Review of the Association Between Mental Effort and Negative Affect”, 2024-07-18 (; similar):
In practice, employers and educators often stimulate employees and students to exert mental effort. On the surface, this seems to work well: Employees and students are indeed often observed to opt for mentally-effortful activities. One may be tempted to conclude from this observation that employees and students may readily learn to enjoy mental effort.
Our results suggest that this conclusion would be false: Our meta-analysis shows that mental effort feels unpleasant across a wide range of populations and tasks.
This insight is important for professionals (eg. engineers, educators) who design tasks, tools, interfaces, materials, and instructions. When employees and students are required to exert substantial mental effort, it is sensible to support or reward them (eg. by providing structure, by balancing demanding tasks with tasks that foster engagement, or by highlighting achievements).
[OSF] Influential theories in psychology, neuroscience, and economics assume that the exertion of mental effort should feel aversive. Yet, this assumption is usually untested, and it is challenged by casual observations and previous studies. Here, we meta-analyze (1) whether mental effort is generally experienced as aversive and (2) whether the association between mental effort and aversive feelings depends on population and task characteristics.
We meta-analyzed a set of 170 studies (from 125 articles published in 2019–2020; 358 different tasks; 4,670 unique subjects). These studies were conducted in a variety of populations (eg. health care employees, military employees, amateur athletes, college students; data were collected in 29 different countries) and used a variety of tasks (eg. equipment testing tasks, virtual reality tasks, cognitive performance tasks). Despite this diversity, these studies had one crucial common feature: All used the NASA Task Load Index to examine participants’ experiences of effort and negative affect.
As expected, we found a strong positive association between mental effort and negative affect. Surprisingly, just one of our 15 moderators had a statistically-significant effect (effort felt somewhat less aversive in studies from Asia vs. Europe and North America). Overall, mental effort felt aversive in different types of tasks (eg. tasks with and without feedback), in different types of populations (eg. university-educated populations and non-university-educated populations), and on different continents.
Supporting theories that conceptualize effort as a cost, we suggest that mental effort is inherently aversive.
[Keywords: effort paradox, feeling of effort, subjective effort, cognitive effort, NASA Task Load Index]