The U.S. has tragically surpassed 400,000 COVID-19 deaths, and case numbers and hospitalizations are likewise spiking to record levels around the world. With vaccines now rolling out out, there is reason to hope that there is an end in sight. However, by most estimates, widespread vaccinations will not be in place until the middle of the year at the earliest. So, we have some ways to go yet with social distancing, mask wearing and other pandemic mitigation behaviors.

It is worrying, therefore, that the world is witnessing a consistent decline in compliance with these mitigation behaviors over time. For example, a Gallup poll from the fall that tracked social distancing habits among Americans found that the percentage of respondents avoiding small gatherings declined by 40 points since April, while those avoiding public places declined by 25 points. Public health experts term this phenomenon “pandemic fatigue” and cite it as a contributor to the increase in incidence rates being witnessed here and in Europe.

Understanding pandemic fatigue is challenging because pandemic fatigue is not one phenomenon and likely stems from several causes. Some of these include political and social trends, such as changes in libertarian attitudes or diminishing trust in scientific authorities. However, pandemic fatigue also occurs for people who are ostensibly on board with societal attempts to control spread of the virus. So, why would compliance with public health advice decline in these people? Despite its name, pandemic fatigue in these cases is not really about exhaustion or tiredness or depleting a mental resource. Rather, pandemic fatigue should be understood in terms of motivation for the tasks we choose to do. As such, lessons from the psychology and neuroscience of cognitive control may be informative.

Humans have a remarkable capacity to conceive of a task they have never done before and plan and execute the actions needed to do it. For example, most of us probably didn’t have a routine of wearing a mask around other people before this year. But, once we understood that it stemmed the spread of COVID-19, many of us started doing so. It didn’t take hundreds of trials of training to learn this behavior, or indeed, thousands of years of evolution. Rather, we incorporated mask wearing into our daily lives almost immediately. Humans can link our abstract goals, ideas, rules and knowledge to our behavior at a speed and on a scale that no other species can match and no AI yet built can emulate. We can do this because of a class of function scientists term cognitive control, a function that is supported by several interacting systems and mechanisms that are uniquely elaborated in the human brain, including the prefrontal cortex.

Importantly, cognitive control is motivated. When deciding to do a task, our control system balances at least two factors: the value we get from doing that task and the costs we will experience while doing so. The former is obvious. Experimental studies on people’s choices about what tasks they would like to do tell us that they prefer and engage more with tasks that lead to desired outcomes, whether that outcome is money, good health, companionship or whatever else they value. Importantly, however, our control system also takes account of our mental efficacy when computing this value, as in how much mental investment is needed to gain from a particular task.

Thus, people won’t do just any amount of mental work for any outcome. Difficult tasks, and particularly tasks involving heavy mental investment, come with an aversive experience of mental effort. People treat that mental effort as a cost that discounts whatever value might be gained from a task. The reasons for these effort costs are still open, but one promising explanation is that they derive from opportunity costs. We can’t do more than one difficult task at a time. So, we penalize difficult tasks because they limit our ability to gain value by performing other tasks. Thus, when we decide to perform a task, our brain does a cost-benefit analysis: weighing our gains against our mental pains.

Life during the pandemic is brimming with tasks requiring control and mental effort, and so the widespread subjective experience of mental exhaustion is not surprising. We are constantly adjusting to new rules and policies. Everything from working to getting groceries to holiday shopping is different than what we know, involves new rules and protocols, and so requires cognitive control to plan out novel behaviors and monitor what we’re doing every step of the way. And for many of us, we are faced with ongoing costs of multitasking, dividing attention between work, children and other priorities all at once. To succeed in this environment requires heavy engagement of our control systems, and so we experience the cost of this mental effort. Changes in either the perceived value or efficacy of these behaviors will make those effort costs harder to tolerate over the long term and compliance will decline.

What can be done? It follows from this analysis that addressing pandemic fatigue requires a robust and multipronged response that addresses not only the political and social aspects, but also motivation in terms of costs and benefits of mitigation behaviors. One target is the opportunity cost. While we are social distancing or sheltering in place or homeschooling our children, we are not doing other valuable things. Many people are unable to work remotely, businesses are slowed or closed, and we are separated from loved ones. Thus, left on its own, the value in complying over time, discounted by its mental effort, is increasingly outweighed by the value in not doing so.

This is one reason that economic relief from a larger individual stimulus relief package, such as that recently passed by Congress, is needed; not only because it provides economic relief, but also because it addresses this opportunity cost of compliance. Second, as noted above, our willingness to invest mental effort in a task is dependent on our belief about the efficacy of doing so. The more difficult the task, the more likely a positive outcome needs to be. Misinformation is rampant, and we still lack consistent guidance from federal leadership about what effective actions to take, from sanitization protocols to how to open schools safely. We need a clear set of guidelines that we know to be effective from an expert source, like the CDC, in order to balance against our experienced effort costs. Relatedly, once an effective set of rules are in place, we need those rules to be as stable as possible. Planning and adjusting to ever-changing policies and procedures for basic living places near constant demands on our control system to manage every task as new.

By contrast, keeping the situation stable allows us reduce effort costs by integrating a consistent set of behaviors into our daily habits and routines. Finally, living and working all together in the same place, such as our homes, results in a state of immersive multitasking. We do not have separate environments for work tasks and home tasks, and so they interfere with one another, which puts demands on our control system that we experience as effort. And multitasking costs are particularly severe for parents with young children. So, measures that help reduce this burden, such as safe procedures for opening schools and places of work, will greatly help reduce these mental costs.

One fundamental facet of pandemic fatigue is motivational in nature and is related to the demands life during a pandemic places on our systems for cognitive control and the mental effort costs this incurs. Measures like those described above that help reduce the costs of mental effort may help stem its downward pull.