I’ve written before about how energy-hungry the brain is. Humans have sacrificed many other evolutionary advantages to have bigger brains. But a more basic question lingers: How does the brain metabolize energy?

The brain consumes up to 20 percent of our body’s energy but is not a traditional kind of organ. It is essentially a massive series of tubes and receptors through which blood is pumped. It’s a finicky organ; if it is denied oxygenated blood for more than 10 minutes, it begins to die, unable to set up any sort of damage mitigation process. If it’s whacked too hard against the sides of our heads, it’ll get bruised and hemorrhage and won’t function properly. If we get too much water near the brain stem, our brains will literally begin to drown.

Nevertheless, we protect our brains fiercely, even though we theoretically could continue to exist and reproduce without them. It is still arguably the part of the body most shrouded in mystery, and the national BRAIN initiative launched with $46 million in funding last year to give researchers and medical professionals a more full picture of how the brain works.

However, this basic question about how the brain processes energy is just now being explored. A recent study conducted by professors from the University of Rochester and the University of Copenhagen shed a little more light on how the brain consumes energy.

The rest of the body’s metabolic cycle operates on the body breaking down sugars and carbohydrates and turning them into glucose which is combined with oxygen in the cells’ mitochondria. It is then sent out into the bloodstream on red blood cells. Plenty of things can go wrong with the metabolic cycle, many of which are genetic or epigenetic and affect our ability to process and use energy.

Researchers traditionally thought the brain metabolized energy through structures known as astrocytes. However, the neurons of the brain take a more active role, acting independently of the astrocytes, according to the study, published in Nature Communications.

One working model for how the brain converts energy is known as the lactate shuttle hypothesis. It theorizes that the brain’s cells convert glucose to lactate and “shuttle” it between cells as a raw form of energy. It is the predominant theory for how the brain, muscles, heart and liver convert energy. Lactate is a more accessible form of sugar that the brain’s metabolic system can use, and the neurons and astrocytes process the glucose so the neural cells can access the energy.

However, the more surprising finding in the study was that the neuronal network plays a more independent role in sugar processing than previously thought. The neurons display a dynamic sugar uptake pattern — when they are more stimulated, they take up more glucose, as compared to the astrocytes, which take up glucose at a constant rate. This displays a more widely functioning brain network than we were previously aware of.

Essentially, the brain’s metabolic cycle is a different beast than we have been able to study elsewhere in the body. Providing a more detailed timeline of how it behaves and what we can do to improve its efficiency or regularity could intervene in the development of many neurological conditions, such as Alzheimer’s.

It also illuminates a little more about ourselves. Our brain’s are arguably the most significant, formative part of who we are. Science, from the rudimentary to the empiric, has probed at the question of how the brain can be preserved and improved. (Many will remember the “science” of phrenology, thankfully, from our history books.) The advancement of empirical understanding of the brain has done away with the theories of racial superiority based on brain size, of differences between men and women based on brain function and with the idea that we are painfully unique on Earth. Even small studies like this one can inch us closer to understanding both ourselves and where we fit on the evolutionary spectrum.