Although it’s been about 4 months since the New Year, the start of summer is another perfect opportunity to get back on track with your new year’s resolutions. And this time, you’re going to stick to it because I’m going to explain the science behind your habits and how you can change your brain to change your habits.
Scientifically, a habit is a routine, behavior, or cognitive process that starts spontaneously but is repeated automatically as a result of prior experience (Mendelsohn, 2020). It essentially means that it’s something you do without really thinking because you’ve done it before. For example, brushing your teeth as soon as you wake up, showering before bed, or grabbing a snack as soon as you get back to your apartment even if you’re not hungry. Habits are context dependent which means they are strengthened through repetition and use cues from the surrounding environment. When you perceive a cue, it automatically triggers a response without much cognitive input (Mendelsohn, 2020). In the example above, the cue is getting back to your apartment and your habit is grabbing a snack, because you’re normally hungry when you get back. But today, you ate a bigger lunch and even though you aren’t hungry you carried out your habit, why?
The relationship between the cue and the response is strengthened by dopamine, the same molecule that keeps you scrolling on tiktok even though you have to wake up in 5 hours. This means that habits are strengthened and rewarded, urging you to carry them out over and over again. When you do something for the first time, your prefrontal cortex is highly active, aiding in carrying out complex cognitive behavior, attention, and decision making. As you continue to carry out the response, dopamine is released by two other brain regions known as the Ventral Tegmental Area (VTA) and Substantia Nigra (SNc). Here, dopamine helps facilitate learning by spiking the exact neural pathway carried out if an action is worth carrying out again or repeating. This strengthens the firing of those neurons in relation to one another, a process known as neuroplasticity (more on that later). Once the response has been reinforced with dopamine, it’s tagged for repetition which is facilitated by the corticostriatal loop which connects the cortex to the striatum, the part of the brain responsible for motor control and decision making. Over time, the brain starts to correlate the cue not the action with the reward leading to the automatic nature of habits. Finally, the striatum translates dopamine release into motor encoding so the output is not reliant on cognitive input and the prefrontal cortex but associations with contextual cues (Wyatt, 2024).
This makes it seem like once a habit is formed, it’s an automatic response wired into us for good. Luckily, our brains are constantly evolving, rebuilding, and restructuring, a process known as synaptic plasticity. This means even though it may be hard, we can restructure, rebuild, and begin new habits. Neuroplasticity is the way the brain changes its activity in response to a stimulus by reorganizing its structure, functions, or connections. This can be carried out through a mechanism known as synaptic plasticity in which long-lasting changes are made to the connections between neurons. In order for this to occur, neurons must “fire together to wire together”(Puderbaugh & Emmady, 2023). At the cellular level, this change happens through synaptic plasticity. When neurons repeatedly fire together, they strengthen their connections, a concept known as “neurons that fire together wire together.” When one neuron activates another, it releases glutamate, an excitatory neurotransmitter. With repeated activation, receptors like AMPA and NMDA work together to increase the sensitivity of the receiving neuron. Over time, this makes the connection stronger, meaning the same signal produces a bigger response. This is how repeated behaviors become more efficient and automatic in the brain. This is obviously really cool science, but how do you use this to form new habits?
It’s clear that habits require repetition whether it’s strengthening the synapses between neurons or the control of actions shifting from the prefrontal cortex to the striatum. But repetition can be hard when your brain has already been wired to do something different so here’s some tips to get your brain to repeat actions that aren’t yet habits until they become one.
- Write down why your new habit made you feel good
The reward pathway and dopamine are key players in why we carry out habits but unfortunately actions don’t feel like a reward until it’s been repeated over and over again. Taking time to think about why your new habit was a good one, and how it made you feel can release some of the “feel good” neurotransmitters and activate the same reward pathways that led to habit formation initially.
- Habit stacking
Stack new habits into a routine you already have. For example, if you always brush your teeth right when you wake up but forget to take your vitamins, start taking them right after you brush your teeth. This helps link the new behavior to already existing neural pathways making it easier to reinforce through repetition.
- Start small
Because your brain has wired your habits rendering them automatic, it takes a large cognitive load to override them. By starting small, you lessen the cognitive load and reduce the demand on the prefrontal cortex making it easier to start the task. For example, instead of saying you need to workout, start by saying you’ll go to the gym for 20 minutes.
- Pay attention to cues
Habit formation is highly cue dependent so start paying attention to the cues that trigger certain habits. The next time you see the cue, you are more likely to break the automatic control of the striatum and engage the decision making and cognitive processing of your prefrontal cortex.
Although habit formation may seem hard, your brain is built to be changed if you let it. Now that you know the science behind changing your brain, the summer is a great time to start!
Sources:
Exploring the brain’s relationship to habits | nsf—U. S. National science foundation. (2013, January 14). https://www.nsf.gov/news/exploring-brains-relationship-habits
Mendelsohn, A. I. (2019). Creatures of habit: The neuroscience of habit and purposeful behavior. Biological Psychiatry, 85(11), e49–e51. https://doi.org/10.1016/j.biopsych.2019.03.978
Puderbaugh, M., & Emmady, P. D. (2026). Neuroplasticity. In StatPearls. StatPearls Publishing. http://www.ncbi.nlm.nih.gov/books/NBK557811/
Wyatt, Zoe. (2024). The Neuroscience of Habit Formation. Neurology and Neuroscience. 5. 3. 10.33425/2692-7918.1063.
