Why are vacations good for the brain?

We have been very happy for the past few days, knowing that, as soon as we finish this article, we are going to enjoy a much-deserved vacation. That’s because the benefits of a good vacation can be felt even before they start. Scientific studies show that looking forward to a future reward can be even more rewarding than the reward itself. This is thanks to a small molecule called dopamine, which we will talk about later.

But before we continue, let's ask a few questions. Are vacations really necessary? Why do we need them? And, above all, what are the benefits of spending a few idle days?

Rest improves cognitive flexibility

Although it may seem surprising, there is little scientific literature that explores the direct benefits of vacations on our brain. What does seem to have been confirmed is that they are essential. This was the conclusion reached by a 2016 study of 46 workers from a Dutch company.

These participants were asked to take a test in which they were given objects (for example, a hammer) and asked for the greatest number of uses in the least amount of time (construction tool, weapon, or paperweight). What they observed is that, after two to three weeks of vacation, the workers had greater cognitive flexibility. Or in other words, they were able to give a greater number of uses to the objects compared to the results obtained a couple of weeks before the holidays.

Most studies agree that, from a biological point of view, one of the main causes of this increase in cognitive flexibility – and of the benefits of vacations in general – is stress reduction.

We all agree that work generates stress. But here we have to make a small aside: stress in and of itself does not have to be bad. When it happens on one-off occasions, it is usually even beneficial, because it activates mechanisms that help us carry out the daily actions of our work, such as meeting a deadline (this is what the authors of this article are working on right now).

The “other stress,” the one with negative connotations for everyone, is chronic stress. This occurs when stress is prolonged over time, either because we are under constant pressure or because of situations that we cannot resolve. It causes fatigue, higher levels of anxiety, irritability and anger. And yes, it is definitely bad.

How to ‘recharge your batteries’

The main thing that a good vacation can do for our mental health is to reduce levels of chronic stress. By having time to relax, our brain will be able to reverse, at least temporarily, the negative effects of being stressed. And here comes the key: for vacations to be really effective, we have to ensure that they really free us from the stress of work. That is, we must avoid trying to finish pending tasks, answering emails, etc.

It’s also important to ensure that our vacations don’t lead to new stressful situations, such as endless queues or prolonged periods with the in-laws.

Another key is to enjoy the wait. Why are we already happy waiting for the holidays? A few paragraphs back we mentioned dopamine, which is produced by neurons in a pair of brain regions known as Substantia nigra (Latin for “black substance,” named so for its dark color under the microscope) and Ventral Tegmental Area (located in the center of our brain, more or less behind the ears).

Both regions, which in humans contain between 400,000 and 600,000 neurons, send axons to numerous areas of the brain. And through the release of dopamine, they play a key role in the pleasant sensation that is generated by novelties and rewards. Therefore, knowing that the holidays are coming increases dopamine levels in our brain and gives us that feeling of pleasure.

For that same reason, the best vacations are those in which we are exposed to novelties – like visiting different places – and rewards – like that seafood platter that we have been waiting for all year. Of course, what is rewarding is completely subjective, and what is pleasurable for one person can create stress for others.

Impact of chronic stress

This system that generates pleasure is also affected during chronic stress. Studies show that high or chronic levels of stress, such as those we are subjected to throughout the year in our working day, are able to reduce the amount of dopamine that is released or change how it is metabolized.

The worst thing is that the changes do not occur only in the Substantia Nigra or in the Ventral Tegmental Area, but also in the places where they send their axons. Chronic stress has even been shown to be able to change the number of dopamine receptors in the areas that receive its projections. When this happens, depressive behaviors often develop. Therefore, a vacation that frees us from stress will help to rebalance the dopaminergic system.

What is not yet entirely clear is whether taking vacations for a prolonged period is better than taking them in intervals and for shorter periods.

Either way, good vacations are good for us. So we encourage you to find activities that make you feel good, recharge your batteries, reduce your stress levels and balance your dopaminergic system. Happy Holidays!

Juan Pérez Fernández is a researcher, with a Ramón y Cajal grant, at the Center of Biomedical Research (CINBIO), in the Cellular Biology area, Department of Functional Biology and Health Sciences, University of Vigo.

Roberto de la Torre Martínez. Department of Neuroscience, Karolinska Institutet.

This article was originally published on The Conversation. You can read the original in Spanish.