“If the energy stops flowing, there’s no more you. There’s no more consciousness, there’s no more emotion, there’s no more life.”
That is the starting point for Martin Picard, a psychologist and mitochondrial biologist at Columbia University, and the central claim of what he calls the “mitochondrial theory of mind.” It is an idea that challenges a fundamental assumption in neuroscience: that consciousness is strictly a property of neural circuits. Picard proposes that the tiny organelles powering every cell in the body, mitochondria, play an active, essential role in shaping cognition, emotion, and the experience of being alive.
The Engine of Experience
Every thought, every emotion, every conscious moment depends on energy. The brain consumes roughly 20% of the body’s total energy despite making up only 2% of its mass. That energy comes from mitochondria, the “tiny transformers” within each cell that convert oxygen and nutrients into ATP, the molecular fuel that powers everything neurons do.
But Picard argues that mitochondria do more than supply power. They are active participants in the cellular conversation that generates mental life. Mitochondria produce the raw materials for neurotransmitters like glutamate and acetylcholine. They catalyze the first step in synthesizing steroid hormones, cortisol, estrogen, testosterone, that regulate mood, sleep, and stress. They buffer calcium, which controls muscle contraction and gene transcription. They generate reactive oxygen species that activate immune cells and relay growth signals. They detect cellular stress and can trigger programmed cell death if damage is too great.
“The flow of electrons from food to oxygen, via mitochondrial metabolism, is the most basic level of the experience of being alive,” Picard told Quanta Magazine.
A Map of the Mind’s Energy System
In 2025, Picard co-authored a study in Nature that produced a mitochondrial map of the human brain, showing that mitochondria vary strikingly across brain regions and even between cell types within the same region. The paper was described as “a milestone towards understanding how brain mitochondria are linked to cognitive function and neurological health.”
That anatomical work builds on earlier findings. In a 2015 experiment, mice with different mitochondrial defects were subjected to immobilization stress. The result: different mitochondrial defects produced different molecular signals in response to the same psychological stressor. “If you change mitochondria, you change how the organism perceives or responds to mental stress,” Picard said.
A 2014 experiment showed that even when mitochondria’s energy-transformation ability was untouched, altering the organelles changed host cell gene expression and growth, supporting the idea that mitochondria function as a dynamic interface between the genome and the environment.
The Metabolic Chamber
Perhaps the most direct test of the mitochondrial theory of mind is an ongoing metabolic chamber study in which Picard himself served as the first participant. For 24 hours, he lived inside one of only 50 metabolic chambers worldwide, a sealed room that measures every calorie burned, every breath exhaled. Blood was drawn every hour, saliva sampled regularly, and mood logged throughout the day. Lights out at 11 PM, no naps allowed.
Preliminary results, presented by graduate student Evan Shaulson, show that people with mitochondrial disease burned 180 more calories per day and 15% more energy even while sleeping, yet reported more fatigue and stress. Their biomarkers showed elevated lactate, a sign of faulty mitochondrial performance that correlated with anxiety.
A striking finding emerged when participants were tracked in free-living conditions using isotope-labeled water: healthy subjects expended 16% more energy outside the chamber than inside, but mitochondrial disease patients spent only 5% more. The implication: the chamber’s controlled restrictions resemble a normal day for those with mitochondrial dysfunction.
The next phase will enroll 100 participants with six months of monitoring using wearables, an app, and regular saliva samples.
From Skepticism to Interest
The mitochondrial theory of mind remains far from mainstream. “Martin is a good thinker, sometimes a little wild,” said José Antonio Enríquez, a molecular biologist at the Spanish National Center for Cardiovascular Research. “His claims really have to be evaluated thoughtfully and scientifically.”
But the idea is gaining traction. Immunologist Jon Brestoff of Washington University recalls that when he first started working on the connection between mitochondria and the immune system, “people literally laughed at me seven years ago. Now people are asking for help.”
The core challenge for the field is moving from correlation to causation. Demonstrating that mitochondrial dysfunction correlates with mood disorders, fatigue, and brain fog is one thing. Showing that specific changes in mitochondrial behavior cause specific mental states is another entirely. Picard’s metabolic chamber study, together with the brain atlas and ongoing molecular work, is designed to build that causal bridge.
What It Means
If Picard is right, the implications extend beyond neuroscience to medicine. Mental health conditions like depression, anxiety, and chronic fatigue could be understood, and potentially treated, as disorders of cellular energy metabolism, not just as problems of neural wiring. Mitochondria, as Picard puts it, are “the portal between the inert genome and the dynamic environment,” the interface where the physical world meets subjective experience.
Sources
1. R. Nuwer, “Martin Picard’s Mitochondrial Theory of Mind,” Quanta Magazine, July 17, 2026.
2. E. Shaulson et al., Metabolic chamber study (preliminary results, under review), presented at conference.
3. M. Picard et al., “Mitochondrial map of the human brain,” Nature (2025).