From a Spark to a Bonfire: Understanding and Nurturing an Interest-Based Nervous System
Imagine you’re trying to build a fire.
You start with a spark, something small but full of potential. If it’s set up well, protected, and fed the right way, it catches. A few twigs turn into flames. With the right fuel and proper care, it quickly becomes a glowing bonfire.
For many neurodivergent people, especially ADHDers and autistic people, that’s very similar to the way our nervous systems work. Our ability to do things usually starts with just a small bit of kindling: interest. Our energy, motivation, focus, and well-being are all sparked by genuine interest.
If that spark of interest is nurtured, it can grow into productivity or deep engagement, even creativity.
But if the spark is ignored or smothered, it doesn’t just go out; it can leave us feeling dysregulated, unmotivated, and defeated.
What Is an Interest-Based Nervous System?
In a typical (neurotypical) brain, motivation is often built on external rewards and consistency. People are expected to show up, push through, and perform, regardless of whether they’re interested. The assumption is that with enough discipline or routine, motivation will follow. The people who are able to follow that model have what’s called an importance-based nervous system; they are able to do things because they just know they need to.
This model makes sense, on the face of it! Everyone kinda has to follow that, right? It’s very often the expectation, and is often framed as just the way the world works.
The vast majority of people don’t exactly get stoked to do their taxes, for example, but we are all expected to make it happen anyway. For the majority of the population, the threat of the consequences of not doing your taxes is enough to get them going.
For many neurodivergent people, though, that threat of consequences isn’t going to spark anything. That’s just not how our brains work. A lot of us, especially those of us with ADHD, have what’s called an interest-based nervous system, a term coined by Dr. William Dodson.
Our nervous systems activate through things like genuine curiosity, excitement, and connection. Interest isn’t a luxury, it’s the ignition. Without it, the engine doesn't start. It’s not about laziness, lack of willpower, or bad habits. It’s just how our brains are wired!
A Quick Bill Nye Moment
So now, the science. What’s actually happening here?
When we talk about the interest-based nervous system, we're talking about the way our brains decide what to pay attention to and how much energy to give it, based on what genuinely sparks our interest. It’s not just about rewards or consequences; it’s about what lights us up.
At the core of this system are a few key brain regions that work together like a team:
The prefrontal cortex, which handles planning, decision-making, and all those executive function skills like focus and follow-through.
The limbic system, which helps process emotions and motivation.
The basal ganglia, which is deeply involved in habit formation and how we respond to rewards.
These parts of the brain are constantly working together to ask,
“Is this worth our attention? Is this interesting enough to put energy into?”
The Role of Dopamine (And Its Friends)
What is (and isn’t) Dopamine?
Dopamine often gets branded as the brain’s “feel-good” hormone, or “pleasure” neurotransmitter, but that’s kind of a simplification. It’s not so much about feeling good, it’s about wanting. Craving. Motivation. Dopamine is the chemical that helps us move toward a goal, pay attention to what matters, and feel driven to finish things.
You can think of dopamine as the “motivated-to-do-the-thing” chemical. Dopamine levels rise for all people when we encounter something new, exciting, or personally meaningful, nudging us to move toward it.
Dopamine is your brain’s internal signal to tell itself,
“Hey, this thing is interesting/important!! Let’s keep going.”
There are other brain chemicals involved in our interest-based nervous systems, too:
Norepinephrine plays a key role in alertness and attention. It helps us notice and respond to what’s going on around us.
Serotonin supports mood regulation, which can also influence how engaged we feel.
For neurotypical people, dopamine tends to show up pretty reliably when a task offers a clear payoff like praise, good grades, a paycheck, or even just the satisfaction of the thing being done. That means people with importance-based nervous systems can often push through boring or unpleasant tasks if there’s a known reward on the other side.
But for many people with ADHD, that signal doesn’t kick in unless the task is genuinely interesting, urgent, or emotionally engaging. If it’s not? It’s like the brain doesn’t “see” the task at all, no matter how important it is.
This isn’t a willpower problem, it’s a dopamine regulation problem.
When ADHDers encounter a task that isn’t engaging or stimulating, it’s genuinely harder to stay focused. Not because of laziness or willpower, but because the brain isn’t getting the internal “go” signal.
What Does This Look Like?
A neurotypical student might be able to sit down and study for a test just because they know it matters. The reward (good grade, approval, finishing) is enough to get the dopamine flowing.
But a neurodivergent student might want to study, understand the stakes, and still not be able to get started unless they find a way to make the task interesting right now. That might mean turning it into a game, racing the clock, using music, or connecting the material to a topic they’re passionate about.
This is also why ADHDers can hyperfocus on something they love (like pulling an all-nighter writing fanfic or reorganizing their Pokémon cards for the 47th time) but struggle to brush their teeth or send one short email. It’s not about personal priorities or intentions; it’s about how the brain prioritizes dopamine.
Neurotypical brains often release dopamine in response to expected rewards.
ADHD brains often need immediate interest or novelty to get that dopamine flowing.
P.I.N.C.H.
According to Dr. Dodson, if a task doesn't hit one of the “PINCH” motivators (Passion, Interest, Novelty, Challenge/Competition, Hurry) neurodivergent/ADHD nervous systems may remain unmoved. He suggests that this wiring drives dopamine production, so genuine engagement is really the catalyst for focus and action, as outlined above.
The ups and downs of an interest-based nervous system can look like:
Struggling to complete tasks that seem “simple” but feel meaningless or are boring
Getting completely absorbed in something we love for hours without noticing time passing
Feeling overwhelmed, anxious, or shut down when forced to switch tasks or mask our disinterest
Thriving when given autonomy and permission to follow our passions
If the neurotypical nervous system is like a car that can start cold as long as it has the right key, the neurodivergent one might be able to get going with the right key, but it will eventually need the right kind of fuel (interest, novelty, connection, meaning) or it sputters out.
So, our brains don’t reliably activate in response to tasks based on importance alone; they need that spark.
The Spark: Recognizing What Lights Us Up
Every bonfire starts small. So small, sometimes, that many people might miss it. Our loved ones may see the attempts and think we’re sending smoke signals instead of making progress. If we aren’t able to recognize the spark in the first place, we may even feel like we aren’t making progress.
For neurodivergent people, sparks come in many forms. For example:
A topic or activity that we just can’t get enough of
A question we have to find the answer to
A pattern we suddenly recognize
A sensory experience that just makes everything feel right
A cause or community that feels deeply meaningful
A way to connect with others that feels true to who we are
These sparks don’t always look “productive” from the outside. Sometimes they show up as hyperfocus on a niche topic, a sudden creative burst, or deep dives that others dismiss as “just a hobby.” But for us, these aren’t distractions—they’re vital signals from our nervous system saying, “Yes. More of this!”
I’ll give you an example: I love basketball.
Though I’m tall, I’m also horribly clumsy, so my abilities really top out at the occasional (lucky) deep 3-point shot on my mini basketball hoop at home… I’m mostly able to participate in this interest by watching all levels of basketball, talking about it with friends and online communities, nerding out about stats, doing deep dives on the more technical aspects or the history of the game, and devouring every bit of worthwhile analysis I can find. I’ve been known to go full sicko mode: watching 2-4 games at once while also looking up stats, texting group chats of my basketball-loving friends & family, and updating my own personal stats spreadsheets (yeah, you read that right) throughout.
Is this “just a hobby”? To an AuDHDer like me, it’s much more than that. Some days, it feels like this hyperinterest (my preferred term over “special interest”) is the lifeblood that keeps me moving and motivated. Some days, I don’t light up until I engage with a hyperinterest, like basketball. Recognizing that spark was the first step in using my interest-based nervous system to my advantage.
When we notice these sparks, and start to (even privately) welcome them without shame or resistance, we begin to honor our natural rhythm.
Building the Fire: How to Nurture an Interest-Based Nervous System
So how do we tend to that spark and grow it into something sustainable?
1. Permission to Care
Give yourself (or your neurodivergent loved one) permission to care deeply about things others might find trivial. Curiosity is not a detour; it’s the path.
2. Embrace rabbit holes, follow threads
When something lights you up, follow it. Even if you don’t know where it’s going. That small excitement might lead to breakthroughs, confidence, or just the regulation your nervous system needs.
3. Reframe “Productivity”
When it comes to personal development, not everything has to have a direct, external outcome. Engaging with interest for its own sake builds regulation, focus, and stamina. That’s productive! Those are all skills you’ll bring into your “productive” activities later on, and you’ll be thankful you built these skills when it’s time to call on them later.
4. Honor Energy Patterns & Needs
Sparks don’t happen on command. Trust the ebbs and flows. When energy is low, rest. When it rises, ride the wave!
5. Build a Fire Ring
Fires need boundaries to burn safely. For an interest-based nervous system, structure doesn’t necessarily mean rigidity, it means creating a supportive environment: tools, rituals, relationships, or environments that let interest flourish without burning us out.
We do sometimes get stuck in rabbit holes, and letting ourselves be absolutely unfettered can make us even feel more burnt out, especially if we still have to go finish the things we need to do to show up as good students, friends, partners, family members, or adults. Building systems around these things is important!
Protecting the Flame
The hardest part of living with an interest-based nervous system, in a world that doesn’t understand it, is the pressure to ignore our own ignition. We’re told to push through boredom, to conform, to detach from what we care about in the name of “discipline.”
That’s like trying to build a fire without fuel. It leaves us cold, scattered, and feeling incapable.
Instead, let’s normalize stoking the fire.
If you come across people who still hold the antiquated view that progress isn’t valid unless people reach it through these rigid, supposedly “disciplined” methods, it’s ok to tell them that’s actually not how your brain is wired, and that they might want to Google “ADHD + dopamine” or “interest-based nervous system” to learn about how some brains work best.
Instead of that mindset, let’s allow ourselves and our loved ones to be intense and passionate. Let’s build workplaces and educational systems that trust and foster deep interest instead of shallow compliance. Instead of asking people to be more disciplined, maybe we start asking what genuinely moves them, and build from there.
Remember: interest isn’t a loophole or a crutch; it’s the fuel. When we honor that, we unlock real motivation, not just performance for performance’s sake.
Listen to Your Nervous System
So, if you’ve ever felt that you can only get traction when something truly interests you, good!! That’s your nervous system speaking its native language. Instead of fighting that rhythm, what if you worked with it?
Start by identifying your spark, getting clear on your mission, and then building the fire that fuels real momentum.
You can try using the worksheet to walk yourself through the process, one spark and one step at a time.
Click image to download PDF
Learn More
“Interest-Based Nervous System: Understanding ADHD and Motivation” Neurodivergent Insights
“The Interest-Based Nervous System and ADHD” Authentically Emily
“How Can Neurodivergent Individuals Find Motivation in Their Own Way? By Susan George” New Directions Psychology
“Episode 59: ADHD Interest-Based Nervous Systems” Divergent Pod
“The Interest-Based Nervous System: Understanding Its Impact on ADHD & Beyond” NeuroLaunch
