The power of habit

For almost ten years, the parking lot at work had been the same—and even though we didn't have assigned spaces, I usually parked in roughly the same spot every day. Then last month, minor construction moved the entrance and exit gates from one parking lot to another, farther away from where I usually park, and with no way to cross from one lot to the other. The result was inevitable: I spent more than a week getting out of the parking lot wrong.

The first few times, I simply drove to where the old gate used to be, only to realize my mistake and turn around. Over the next few days, I gradually improved: I still automatically entered the wrong lane, but each time I noticed my mistake a little earlier.

Finally, last week, my brain learned: I am now able to get in the car at the end of the day and drive straight to the exit. The similarity of my situation to that of laboratory mice undergoing learning and memory tests did not go unnoticed, of course—it's all part of the job.

It was actually fun to experience firsthand (or first brain) how difficult it can be to extinguish one habit and acquire another in its place. It's a very mild version of what various addicts need to achieve in order to kick their respective habits: reprogram their brains to break a habit.

The source of the difficulty is the same process that, in other circumstances, gives us the advantage of not having to consciously think about how to do what we need to do when it comes to behavior that is always performed in the same way. These are habits, inscribed in our brains in the connections between the motor cortex and the basal ganglia, and performing them does not require attention. Just be in the right context, and the program automatically launches while you think about something else—hence my systematic mistake right after changing parking spots.

Habits, therefore, are extremely valuable as long as conditions do not change—and problematic when they do. Fortunately, the same repetition that leads to the formation of habits is also the remedy for updating them, especially when we have a chance to consciously remember beforehand that a change is necessary: “the exit is over there, the exit is over there...”

Excerpted from Suzana Herculano-Houzel (2025) Neurociência da Vida Comum (Neuroscience of Everyday Life), originally published in Folha de São Paulo in April 2012.