What’s the science?
The neuroscience world has long believed that expending effort is costly, and therefore humans generally avoid it. Recently, in Trends in Cognitive Sciences, Inzlicht and colleagues bring together evidence to suggest that effort — for example, running a marathon — can actually be rewarding.
What’s the literature?
Effort in this case is defined as an agent's (i.e. a person’s) intentional mental or physical exertion to achieve a goal. This is distinct from difficulty, which is a property of a stimulus, not an agent. The literature shows that effort is costly, and results in negative physical consequences. A region of the brain called the anterior cingulate cortex has been shown to be involved in effort and the avoidance of effort. There is also behavioral evidence showing that we will choose the less effortful option, if given an equal reward for both options. Further, we will sometimes accept fewer rewards to avoid effort.
There is growing evidence to suggest that effort can be rewarding. Research shows that people assign a higher value to rewards from tasks that are effortful (for example assembling IKEA furniture). Furthermore, brain centres associated with reward activate more in response to the reward when a task requires more effort. People also give more rewards (i.e. money) to others when they perform an effortful task, for example giving more to charity for a 5k run vs. giving to a charity picnic. One possible explanation is that the brain processes effort as a signal for future reward, much like a bell signals food, producing effort-reward associations. Effortful acts have been reported as rewarding in themselves, for example in mountaineering, suggesting that effort is not only rewarding in retrospect, but can also be rewarding prospectively.
What’s the bottom line?
Evidence shows that effort can be both costly and rewarding. In the past we have largely considered effort as something humans tend to avoid. We now have a more balanced view of how our brain may evaluate effort. There may be a limit for when effort is no longer rewarding, or types of effort that are not rewarding. More work is needed to determine when effort is costly vs. rewarding.
M. Inzlicht. The Effort Paradox: Effort is Both Costly and Valued. Trends in Cognitive Sciences (2018). Access the original scientific publication here.