Things that I have found about the human brain that I didn’t know…

I am becoming really really fascinated about how the human brain works and have evolved. I’ve been reading, assisting online videos and participating on webinars to know more about this theme. Below, I am going to list the 7 things I learned that really have surprised me.

1. We have on average 86 billion neurons where 16 billion are on the cerebral cortex. In spite this number looks incredibly giant, we are not the animal with the highest number of neurons — whales, for example, have a much higher number of neurons. However, when comparing our brain with other animals, we care about numbers of neurons in the cortex as is the area of the brain that controls higher-level processes such as logic, reasoning, creative thinking, language, complex social interactions, allowing us to learn from the past and make plans for the future. And happens that, we have by far the largest number of neurons in the cerebral cortex when compared to the size of our brain.
2. Although our cerebral cortex is one of the largest among mammals in its relative size (~75%), we are not special because of that, as animals like the chimpanzee (~73), horse (~74.5%) or short-finned whale (~73.4%) have similar percentages. As I mentioned above, what makes us different is the number of neurons we have in our cerebral cortex when compared to the size of our brain.
3. It’s a myth that we only use 10% of our brains. We use 100% of our brain. We even use more than 10% when we sleep.

4. Our brain can change throughout our life and that is called neuroplasticity. There are 2 types of neuroplasticity:

• Functional plasticity: The ability of the brain to move functions from a damaged area of the brain to other undamaged areas.
• Structural plasticity: The ability of the brain to actually change its physical structure as a result of learning, activities, thoughts or/and experiences. This basically means our actions and our thoughts can literally change the “shape” of our brain.

5. Our brain weighs around 1,2kg — 1,5kg which represents around 2% of our body mass, however, absorbs 20–25% of our total energy, which represents, around 516kcal/day. This happens due to the increased metabolic need of its neurons.

6. 75% of the brain is water. Also, is the water that helps to conduct the electricity across our neurons dendrites, from neuron to neuron.

7. What is the reason for us to be so advantageous with the highest number of neurons in the cerebral cortex? What have we done to deserve that? Basically, we have been eating more effectively than all other species from the last 1.8 million years with the emergence of Homo erectus. We have cooked our meals using fire or heat. This means we make a “pre-digestion” before we eat. Heating our food unlocked nutrition: 100 % of a cooked meal is metabolized by the body, whereas raw foods yield just 30 or 40 % of their nutrients. As we have absorbed the nutrients more efficiently, our brain evolved in a faster way than other species.