It is the beginning of February, and chances are most people have given up on g their New Year’s Resolutions. Every year it happens. Why is it so difficult to build a new habit? Well, first we need to define what a habit is. While different definitions are used in different situations, the strict neurological definition is that a habit is a response that is associated with a stimulus, acquired from reinforced learning.

Our understanding of what underlies habit formation in animals has come on in leaps and bounds in recent times. The main brain areas involved in stimulus-response, or habitual, behaviour, include the substantia nigra and the basal ganglia. The activity of dopamine sensitive (or ‘dopaminergic’) neurons in these regions reinforce certain behaviours, or routines, after registering a stimulus, or trigger.

Researchers have studied this process in rats by looking at the activity of different pathways in the brain while the animal navigates a maze to find some food. The opening of a gate to a maze coincides with a stimulus, usually a sound, and the rat wanders around the maze, using spatial cues to find where the food is. If the rat is guided to turn, say, left, to find the food, over time it will start to automatically turn left without referring to many spatial cues, instead relying on its learned behaviour.

The rat now has a habit of turning left. Even if the food has been moved to the other wing of the maze, or removed altogether, the rat will still turn left. Monitoring the brain during this process shows that once the rat has formed a habit of turning left to find food, the dopaminergic activity spikes, coinciding with the sound, but then there is a notable lapse in activity until the rat finds the food. This suggests that the rat is on autopilot during the maze, paying no attention to spatial cues, acting on habit. Charles Duhigg, author of The Power of Habit, has gone in depth into the science behind habit building and maintaining. He has shown that this initial cue, the sound in this case, is the key to performing the habitual behaviour, regardless of if the reward is still there or not.

You might not like the idea of comparing yourself to a rat in a maze, but this research can be incorporated into our own lives. How many times have you went to make tea for someone else but, due to habit, accidentally made it how you take it instead? By recognising the stimuli that trigger our habits, we can train our brain to associate them with the automatic response. Creating an association between a stimulus and a response helps us to build a habit. It is easier to start going to the gym right after your last class on a Wednesday than it is to ‘start going to the gym’.

Like the rat in the maze, you will eventually just do it on autopilot. So, by being aware of your routines and anchoring new habits to a specific situation or time of day, it is easier for your brain to make these habits automatic. This stimulus-response association is the key to making habits last, so use this to your advantage to get back on track with your New Year’s Resolution.

Danielle O’Rourke – Science Writer