If you’re feeling stressed this Monday, it might help you to look beyond yourself to find something that makes you happy. If you can think of even one person who has shown you the tiniest bit of generosity, consider yourself grateful – and thank them. The act of expressing gratitude may reduce feelings of stress in your life, so find some time this Monday to pay it forward!

The act of expressing gratitude, especially through writing letters, may block negative emotions by putting more focus on positive ones. While it may not be a permanent change in attitude, writing letters of gratitude toward someone else may have a positive impact on mental health. After a gratitude letter has been written, the writer may feel like their mood has changed for the better, as if the letter helped them “snap out of it” if they were in a funk.

At Berkeley, a study was conducted with over 300 adults who reported “clinically low levels of mental health” and were seeking assistance through therapy. They participated in the study before attending their first therapy session. Some were asked to write letters expressing their gratitude once a week for three weeks with the assurance that those letters did not have to be delivered or read by anyone else. After four weeks, the people who wrote gratitude letters reported higher levels of mental health compared to those who didn’t write letters. However, even though the changes were not immediate, it is possible that the writing did allow the participants to focus on the people to whom they were writing and helped them appreciate the positive things while thinking less negatively.

Three months later, the study included fMRI brain scans of the participants to see if there was a physiological effect of expressing gratitude. The scans showed that the letter writers had “greater activation in the medial prefrontal cortex” – the part of the brain that affects learning and decision-making – than the people who weren’t asked to write letters. This suggests that even a simple act of gratitude may have long-lasting effects on the brain and mental health.

If you’ve spent some time in a bad mood or think you need to change your attitude, take a few moments this Monday to write a letter of gratitude. Focus on the positive things that made you appreciate the person to whom you’re writing rather than any negativity you might be feeling. You don’t have to send the letter – even though you can! – but by shifting your focus from your negative feelings to positive actions you could brighten your day and someone else’s!