What makes the human brain so special?

Some features of our brain are absolutely implausible.

The human brain is exceptionally uniqueIt possesses very complex characteristics in relation to all other animal species, including our phylogenetic cousins, the primates.

The capabilities of human beings are highly specific to our species: we can think in very complex terms, we can be creative and create technological artifacts that make our lives easier, and we are the only species with the ability to study other animals and their behavior.

Why are we so special? The human brain...

For years the scientific literature postulated that cognitive capacity was proportional to the size of the brains.. This is not entirely correct, since two mammals with brains of similar size, such as a cow and a chimpanzee, should have behaviors of equal complexity, which is not the case. And what is even worse: Our brain is not the largest brain in existence. However, our brain, despite not being the largest, is the best in terms of cognitive capacity..

Apparently, the special quality of our great cognitive capacity does not come from the size of the brain in terms of its mass, but rather in terms of the number of neurons it contains. And this is where we come across a study by Suzana Herculano-Houzel, a Brazilian neuroscientist, who set herself the task of determining the number of neurons in the human brain.

Prior to her research, the vast majority of neuroscientists believed that the human brain had 100 billion neurons. The truth is that this figure was never determined in any study and was a standard for years in the scientific literature.

Thus, Suzana Herculano-Houzel, through a method she designed, managed to determine the final figure of the number of neurons in the human brain: 86 billion neurons in total, of which 16 billion are found in the cerebral cortex (the cortex involved in complex cognitive processes). And by applying the same method to the brains of different mammals and comparing them, he discovered that the human brain, despite not being the largest in terms of mass, is quantitatively the largest in terms of the number of neurons it possesses, even with primates, with whom we share much of our genetic load (97%). And this would be the specific reason for our cognitive abilities.

Why did humans evolve to this amazing complexity?

From this, other questions arise: How did we come to evolve this amazing number of neurons? And particularly, if primates are larger than us, why don't they have a larger brain with more neurons?

To understand the answer to these questions, one must compare the body size and brain size of primates. Thus, he discovered that, because neurons are so expensive, body size and the number of neurons compensate for each other. So a primate that eats 8 hours a day can have a maximum of 53 billion neurons, but its body could not be larger than 25 kg, so to weigh much more than that, it must give up on the number of neurons.

From determining the number of neurons available to the human brain, it is understood that it needs an enormous amount of energy to maintain it. The human brain consumes 25% of the energy even though it represents only 2% of the body mass.. In order to maintain a brain with such a large number of neurons, with an average weight of 70 kg, we would have to dedicate more than 9 hours a day, which is impossible.

Humans cook food

So if the human brain consumes so much energy and we cannot spend every waking hour devoting ourselves to our food, then the only alternative is to somehow get more energy from the same food. Thus, this coincides with the incorporation of the cooking of food by our ancestors a million and a half years ago..

Cooking is the use of fire to pre-digest food outside the body. Cooked foods are softer, so they are easier to chew and to transform into mush in the mouth, which means that they can be better digested in the stomach and allow the absorption of greater amounts of energy in much less time. In this way, we obtain a great amount of energy for the functioning of all our neurons in much less time, which allows us to dedicate ourselves to our daily activities.This allows us to dedicate ourselves to other things beyond feeding ourselves and thus stimulate our cognitive capacity achieved with a brain of such magnitude.

So what is the advantage we have as human beings, what is it that we have that no other animal has?

The answer is that we have the brain with the largest number of neurons in the cerebral cortex, which explains our complex and extraordinary cognitive abilities in nature.

What do we do, and what does no animal do, to allow us to reach such a large number of neurons in the cerebral cortex?

In two words: we cook. No other animal cooks its food to digest it, only humans do. And this is what allows us to become human as we are.

From this conception, we must realize the importance of food, how food influences the maintenance of our cognitive skills, and the extent to which we have the power to achieve our goals. and the scope we possess in achieving behaviors of enormous complexities.

So now you know: the next time your mother cooks something you don't like or you hear that someone is going to study gastronomy, congratulate them, because with their contributions they continue to ensure that our cognitive skills remain just as complex.