Why Your Brain Chemicals Are Running Your Day (Without Telling You)
I have been quietly optimising my mornings for about a year. Movement first. Then water. Sunlight through the window during journalling. No phone before 8am. Gratitudes before anything else.
I did not build this routine because I understood the neuroscience. I built it because it worked – the days I started this way were measurably better than the days I did not.
TJ Power’s episode on Jim Kwik’s Kwik Brain podcast gave me the explanation for why. The DOSE effect – dopamine, oxytocin, serotonin, endorphins – turns out to be the mechanism behind almost everything I had built instinctively. Once I understood it, I could be more deliberate. And a few things I was doing wrong became very clear.
Table of Contents
Who Is TJ Power?
TJ Power is a neuroscience and performance specialist and the author of The DOSE Effect – a book about the four key brain chemicals that drive human behaviour and how modern life has disrupted all of them. He works with athletes, executives, and organisations on the science of sustainable motivation and wellbeing.
His Kwik Brain episode is one of the most useful fifty minutes of brain science I have encountered – specific, practical, and free of jargon.
Dopamine — The Motivation Molecule
Dopamine is the anticipation molecule. It drives you towards things – towards goals, towards connection, towards the next thing on the list. It is released in the process of working towards something, as well as on achievement.
Here is the problem TJ Power identifies: social media, processed food, and constant stimulation give you dopamine hits for doing nothing. Your brain learns to associate reward with zero effort. Over time, this raises your baseline requirement for stimulation – the bar for what feels interesting goes up, and real life (the effort of writing, the slowness of deep thinking, the patience required by genuine relationship) starts to feel flat by comparison.
The repair: real dopamine from real effort. Completing a task. Learning something new. Making something. The satisfaction of finishing what you started. This is exactly what Atomic Habits describes when it talks about making the reward immediate – giving yourself a genuine completion signal at the end of each habit.
Oxytocin — The Connection Chemical
Oxytocin is released through physical touch, sustained eye contact, genuine conversation, and trust. It is the chemical of belonging – of feeling genuinely seen and connected to another person.
The modern threat to oxytocin is not cruelty. It is substitution. We are physically present in rooms with people while being mentally elsewhere – on a phone, in a thought, preparing the next thing to say rather than listening. Oxytocin requires real presence. Half-presence does not produce it.
I felt this in the post about How to Talk So Kids Will Listen – the quality of attention you bring to a child is not a technique, it is a presence. Adele Faber and Elaine Mazlish were describing oxytocin production without the vocabulary.
The repair: undivided attention, even briefly. Physical contact. Real conversations without an agenda. Eye contact across a table instead of parallel screens.
Serotonin — The Quiet Stabiliser
Serotonin does not produce peaks. It produces a steady baseline of mood, confidence, and equanimity. When it is present, you feel okay – not euphoric, just solid. When it is depleted, everything is harder than it should be.
It is produced by sunlight, exercise, sleep, and gratitude. These are the least glamorous ingredients on the list. There is no shortcut to serotonin. It requires the long, undramatic practices.
This connects to Why We Sleep – Matthew Walker’s research on what consistent sleep deprivation does to emotional regulation is, in part, a story about serotonin. And to Change Your Diet, Change Your Mind – Dr. Georgia Ede’s argument that nutritional psychiatry is real and measurable runs through the same mechanisms.
The repair: morning sunlight before a screen. Exercise. Sleep protected like it matters. A gratitude practice that is not performative.
Endorphins — Natural Pain Relief and Euphoria
Endorphins are the body’s built-in analgesic and euphoria system. They are released through sustained physical effort, deep laughter, cold exposure, and – interestingly – spicy food.
The runner’s high is endorphins. The euphoria of a really good laugh is endorphins. The unexpected uplift after a hard training session is endorphins.
Modern life does not eliminate endorphins the way it disrupts dopamine. But it does reduce them – if you are not doing anything that requires physical effort or produces genuine, side-splitting laughter, the endorphin system is underused. The consequence is a flatness that is hard to name but easy to feel.
How Modern Life Disrupts All Four
TJ Power’s central argument is that modern life has simultaneously disrupted the natural production of all four DOSE chemicals – replacing them with artificial substitutes that produce the feeling without the biological reality.
Artificial dopamine from screens. Absent oxytocin from phone-mediated connection. Depleted serotonin from poor sleep, poor nutrition, and indoor lives. Underused endorphins from sedentary comfort.
The result is a population that is, by many measures, physiologically less equipped for motivation, connection, stability, and joy than any previous generation – while also having more external comfort than any previous generation.
This is not a moral argument. It is a biological one. And the repair is not complicated. It is just inconvenient, because it requires the slow, undramatic, screen-free practices that modern culture does not reward or celebrate.
Practical Takeaways
- Audit your dopamine sources. How much of your dopamine today came from effort and completion? How much came from scrolling, snacking, or passive stimulation? The ratio matters.
- Protect undivided presence. Oxytocin does not accumulate from partial attention. Five minutes of fully present conversation produces more connection than an hour of being in the same room on a phone.
- Treat serotonin like infrastructure. Morning sunlight, movement, sleep, and gratitude are not optional extras. They are the maintenance of your baseline. Neglect them and everything else becomes harder.
- Build in genuine physical effort and real laughter. Not performative wellness – actual effort that earns the endorphin response. Your body needs things that are genuinely hard or genuinely funny.
- When you feel flat or unmotivated, check the basics before blaming yourself. A depleted DOSE profile is a physiological state, not a character flaw. Sleep, sunlight, movement, and genuine connection will move the needle before any mindset intervention will.
Why This Belongs in Mind
Mind on this blog is about learning, belief, and how we grow – and increasingly, how the brain actually works underneath all of it.
The DOSE effect belongs here because understanding your brain chemistry changes how you interpret your own behaviour. When you know that the flatness you feel at 3pm is a physiological state – partly a serotonin dip, partly a dopamine comedown from the morning’s screen use, partly a missed endorphin opportunity – you stop making it mean something about you.
It belongs alongside Limitless (Jim Kwik’s framework for how to use your brain properly), Change Your Diet, Change Your Mind (the food-brain connection), and Motivation Made Simple (Dr. K’s framework for what motivation actually is neurologically). All three are part of the same project: understanding what is actually happening in the brain, rather than just trying to force different outcomes.
I now know why my mornings work. Movement, water, gratitude and sunlight before anything else is not a personality quirk. It is dopamine production through effort, serotonin production through sunlight and gratitude, and endorphin production through movement – all before the artificial dopamine of a phone screen gets anywhere near the equation.
I also now know what is happening at 2pm when everything feels heavier than it should. That is useful information. Not a verdict.
Et toi? When you look at your DOSE chemicals honestly – where are you getting dopamine, oxytocin, serotonin, and endorphins in your day? And how much of it is earned versus artificial? Leave a comment below or come and find me in the Notes from Soph community on Skool.
Notes from Soph | Learning, not perfection.
Source Details:
Kwik Brain – “The 4 Chemicals Secretly Controlling Your Motivation and Mood”
TJ Power | 2025
🎙 Listen on jimkwik.com or search “Kwik Brain” on Apple Podcasts / Spotify
📚 Amazon (The DOSE Effect — TJ Power) https://www.amazon.co.uk/dp/0008667292/?tag=websitenote0f-21
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