The Neurobiology of Habits

Gulf Insider

a day ago

Habits form through rewards and repetition, not just willpower.
Repetition makes actions automatic, freeing up decision-making in the brain.
Dopamine motivates habit formation and reinforces repeated behaviors.
Nearly half our daily actions are habits, shaped by routine.
Whether you are trying to quit smoking or eat more vegetables, changing your habits takes more than willpower. Habits are shaped by how your brain learns and makes decisions. A recent study found that we form habits through rewards and consistent repetition. Changing your habits can be hard, but repetition may be the key to maintaining a healthy routine.
It is easy to think of habits as behaviors that we can choose to start and stop at any time. We want to believe that we are in control of all our actions and preferences. In reality, habits are deeply ingrained patterns shaped by both our environment and how our brains learn over time.
Learning new habits happens slowly, often without you realizing it. When you first learn to drive a car, you consciously think about every action– checking your mirrors, monitoring the road, tracking your speed, and other actions. Over time, as your brain strengthens these neural pathways, driving starts to feel automatic. Once the habit is established, the brain's 'decision-making center' takes a backseat.
Forming a new habit can take anywhere from three weeks to several months, averaging about 70 days. The promise of a reward is often one of the biggest motivators. Knowing that something good awaits you on the other side releases dopamine into the brain. This 'feel-good' chemical motivates you to keep going.
Not every habit gives you instant gratification. Daily habits like brushing your teeth or locking the door when you leave keep you healthy and safe, but they do not have an obvious payoff. It is just part of your routine. The more you do it, the more your brain gets used to the pattern, and it starts to feel effortless.
Nearly 45 percent of our actions throughout the day are habits. You likely do not think about turning off the lights when you leave a room or putting on a seatbelt when you get into the car. Even the route you take to work or to school is automated. Habits also shape our preferences. If you always have a cup of coffee first thing in the morning, you may start to prefer coffee over tea. It may not necessarily taste better, it's just part of your routine.
According to Dr. Marcus Stephenson-Jones, a researcher at the University College London and lead author of this study, 'Once you have developed a preference for a certain action, then you can bypass your value-based system and just rely on your default policy of what you've done in the past.' Habits allow the decision-making areas of the brain to take a break. If you visit a restaurant enough times, you may start defaulting on the same order because it is familiar and your brain does not have to decide whether you will like it.
Recently, the Swedish team discovered that our habits are influenced by two learning systems in the brain that work in parallel. The reward-based system, regulated by the release of dopamine in decision-making areas of the brain, teaches you to repeat behaviors that lead to good outcomes. The repetition-based system reinforces these habits into your routine. Until now, it was not clear what directs our brain to keep repeating these behaviors after the initial sense of reward fades.
Observing mice learn new behaviors uncovered a key piece of the puzzle. The team trained a group of mice to perform a listening and response task. The animals were taught to initiate the task by pushing a button that plays high and low frequency sounds. Depending on the frequency, the mice selected either the left or the right button. The correct answer rewarded the animal with a sip of water.
As the animals learned to associate high tones with one side and low tones with the other, their performance on this task soared. They were able to anticipate each movement, responding faster and more accurately. Their actions became less effortful and more automatic.
Each time the animals initiated the task, dopamine levels spiked in motor regions of the brain. Most of this activity was traced back to a small midbrain region that helps with movement and learning, called the striatum. Surgically removing this region increased the time the animals spent learning the task. Others that were injected with genetic modifiers that block dopamine-releasing neurons in this region also performed poorly, suggesting that this region plays a key role in how we form habits.
Dopamine seems to act as a teaching signal, helping the brain to remember repeated movements. After the residual sense of reward fades, movement continues to trigger the release of dopamine when we are doing something familiar. This offers a new piece of the puzzle in how we form new habits, like going to the gym consistently. When you first go to the gym, you feel good about yourself. Weeks later, you may not feel the same satisfaction, but you keep going because repetition has ingrained it into your routine.
The role that dopamine plays in habit learning may also have implications for Parkinson's disease. Dopamine is a key chemical messenger for coordinating movement. In Parkinson's, brain cells that produce dopamine gradually die off, which interrupts the brain's ability to send the right signals to muscles. This leads to tremors, stiffness, slow movements, and difficulty with balance. Some of these symptoms may be linked to dysregulation of the brain's habit-forming system, which influences automatic behaviors like walking. The findings from this study may have uncovered a new potential treatment target for Parkinson's disease.
Pause and take a moment to think about all the decisions that you make in a day. From the moment you wake up, whether you hit snooze or get up right away, to what you choose to eat for breakfast or the route you take to work, these actions seem to happen almost automatically. But what about the habits you want to change? The most effective way to break a bad habit is by replacing it with a good one. If you know you like to snack on junk food when you are stressed, try going for a quick walk instead. Moving is not just a distraction; it is the key to shaping your habits.