The Science of Gratitude Habits - How "Thank You" Affects the Brain and the Body

The Neuroscientific Effects of Gratitude on the Brain

When you feel gratitude, the medial prefrontal cortex and the anterior cingulate cortex become active. These regions are involved in reward processing, social cognition, and moral judgment, and feeling gratitude releases dopamine and serotonin in the brain. In other words, gratitude sets off the same reaction inside the brain as "having received a reward," without your obtaining anything from outside.

Gratitude is also thought not to end with feeling it once, but to have the property of becoming easier to feel the more it is repeated. The brain raises the transmission efficiency of circuits it uses repeatedly, so if you keep up the work of turning your eyes toward good things every day, the time it takes to pick gratitude out of the very same event grows shorter. Much as muscles grow through strength training, gratitude is closer to a skill in which the amount of practice tells.

How Gratitude Raises Tolerance for Stress

Chronic stress makes the amygdala oversensitive, so that even trivial events readily set off a threat response. A gratitude habit eases this oversensitization. While you are feeling gratitude, the parasympathetic nervous system comes to the fore and heart rate variability (HRV) rises. A high HRV is treated as a rough measure of tolerance for stress, and people who can hold time for feeling gratitude within their days are thought to find it easier to get back from a tightly strung state to normal.

Gratitude also has the effect of weakening the "negativity bias." The human brain evolved to react more strongly to negative information than to positive information, but accumulating practice at deliberately noticing good things gradually corrects this bias. Faced with the same event, people who hold a grateful perspective find it easier to spot its positive aspects.

Concrete Effects on the Body

The effects of gratitude do not stop at the mental side. In an experiment reported in 2016, young women were asked to write down things they were grateful for over about two weeks, and their self-rated sleep quality improved compared with people who did not write. Bringing to mind things you can be grateful for before bed holds back rumination (the state in which negative thoughts go around and around) and lets you fall asleep in a calmer frame of mind.

There is also research that measured changes inside the body. In a small trial reported in 2016, patients with heart failure kept up a practice of writing down what they were grateful for, and their inflammatory markers fell while parasympathetic activity strengthened during the writing itself. Resting heart rate variability, however, showed no difference, so this is not a stage at which the size of the effect can be stated with confidence. Since chronic inflammation forms the ground for many illnesses, this is an area where further verification is awaited.

How to Write a Gratitude Journal Effectively

The most studied form of gratitude habit is the "gratitude journal." Each day you write out three to five things you can be grateful for. If you only write vaguely that you are "grateful for my health" or "grateful for my family," though, the effect thins out. Specificity and freshness are the keys.

Three points maximize the effect. First, write specifically. Rather than "grateful for a friend," pin down the scene: "that a friend went out of their way to call me today even though they were busy." Second, add the reason you feel gratitude. Touch the deeper layer of the emotion, as in "the call let me feel that I am not alone." Third, do not write the same thing every day. The effort of finding new gratitude is training that turns your attention toward "good things." The practice of deliberately cultivating gratitude is a central approach in positive psychology.

What to Do When You "Cannot Feel" Gratitude

In hard periods, feeling gratitude itself becomes difficult. Forcing yourself to think "I have to be grateful" can end in self-invalidation instead. A gratitude habit is not a duty; it is no more than a tool. When you cannot use it, there is no need to.

If you still want to try, lower the bar as far as it will go. Find just one thing that "was not the worst today." "I can breathe." "I have a roof." "I can drink water." Even things too ordinary to mention give rise to a sense of gratitude once you imagine a situation in which they had been lost. The order runs not "you feel gratitude because you are happy" but "you come closer to happiness because you practice feeling it."

The Power of Gratitude in Relationships

Putting gratitude into words and telling the other person is one of the most effective ways to strengthen a relationship. A relationship in which partners tell each other their gratitude in words is thought to hold its level of satisfaction better than one in which it goes unsaid. Saying gratitude out loud is also a signal that "I notice what you did for me," and for the other person it works as confirmation that their consideration has not gone to waste.

A single "thank you" has an effect, but conveying it more specifically is more effective still. "I was really glad that this morning, when I overslept, you made my lunch without saying a word" reaches the other person more deeply than "thank you for always doing the housework." By acknowledging the other person's action specifically and telling them what effect it had on you, gratitude turns from mere courtesy into the expression of a deep bond.

Devices for Making a Gratitude Habit Stick

Quite a few people who start a gratitude journal grow tired of it in about two weeks. To keep it fresh, give yourself variations in how you write. Changing the theme by day, so that Monday is "gratitude toward people," Tuesday "gratitude toward your own body," and Wednesday "gratitude toward nature and your surroundings," lets you look for gratitude from a new angle every day.

Tying moments of gratitude to an "anchor" is also effective. The moment you drink your coffee, the moment you open the front door, the moment you get into bed. Use one particular everyday action as a trigger and bring a single piece of gratitude to mind at that moment. Even without writing in a journal, doing this "micro gratitude" a few times a day strengthens the brain's gratitude circuits. Find a way to practice gratitude intentionally within your day and keep going at a pace that suits you.