Experts vs Myths: Top 5 Misconceptions about Brain Dispelled by Neurobiologist Nana Voytenko
We often hear statements in which we wholeheartedly believe. For example, everyone “knows” that “nerve cells do not regenerate”. Is that indeed the case? Nana Voytenko, the neurobiologist, founder, and vice president of the Ukrainian Society of Neuroscience, will dispel the myths about the human brain.
N.V.: In reality, the size of the brain has no impact on the intelligence level. On average, the human brain weighs 1.5 kilograms. The biggest brain, weighing 2.9 kilograms, belonged to the mentally challenged person, and the brain of the talented writer Anatole France weighed a little bit more than a kilogram. Neurophysiologists think that not the size but the number of neural connections defines brain properties and potential. To improve intellectual abilities, it is important to use the whole brain power and always learn something new starting from childhood.
N.V.: It is not true. Different tasks activate different brain structures. It would be more correct to say that we do not always use our intellectual abilities to the full. Mental processes are very energy consuming, so sometimes people are just too lazy to think. Similarly, sometimes one feels lazy to make any physical efforts – do exercises, walk, go to the gym.
Different factors such as health state, sleep, motivation, environment, influence how full we use the potential of our brain at different times. Besides, the brain potential depends on the number of neural connections activated over the lifetime of a certain person. If a child was not getting some necessary information that activates these connections, as an adult his brain will have less of intelligent potential. It is necessary to maintain the connections activated in childhood during the whole life.
N.V.: It is true only partially. This happens when the person stops training his brain or gets stuck on one mental sphere. People that show interest in something else apart from their profession during life, for example, play chess, do sports, speak foreign languages, read books, do crossword puzzles, lead an active social life, have higher chances to keep their minds clear until the extreme old age.
N.V.: From the anatomical standpoint, men and women have different sizes and structures of the brain. Recent researches have shown that the man’s brain is bigger in size. However, women have thicker cerebral cortex – the brain part related to memory, sensory processing, teaching, and decision-making.
Differences between the brain of men and women are so minor that it is impossible to define the person’s sex by looking at his brain. The size and structure of the brain are the same phenotypic traits as the form of the nose: they depend on many genetic factors and can take an endless variety of forms. It has been proven that these differences are in no way connected with the real abilities of people.
For example, it is a common idea that women have better-developed empathy and emotional intelligence. However, it absolutely contradicts the anatomy of the brain. Men usually have a better-developed amygdala, which is responsible for emotions. While women have a better-developed hippocampus, which is connected to memory. Scientists believe that different sizes of the brain and its standalone structures do not necessarily lead to intellectual inequality. Genetic and social factors play a much bigger role in the development of our intelligence.
N.V.: This statement is not quite correct. Brain cells are capable of regeneration but this process is not as intense as in the case of other organs. Besides, unlike cells of other tissues, neurons are not capable of dividing, so it was considered for a long time that the brain was limited by a number of neurons present at birth.
Now it is precisely known that new neurons still appear in the course of a lifetime – from stem cells. The latter exist not in all brain structures, in particular, they are present in the hippocampus – the brain division responsible for memory, teaching, and emotions. It has been shown recently that new neurons are produced in the hippocampus of elderly people and even people with Alzheimer's disease. However, their number is less than that of healthy people.
The process of new neuron generation is activated when you receive injuries, suffer blood strokes, inflammations, and in the process of studying. Their number is scarce and not all “newborn” neurons survive and become functionally active. On average, around 700 newly formed neurons appear in the brain structure. It is a very small quantity as compared to 100 billion initially existing neurons.
You can learn more about brain functions and peculiarities at Biohacking Conference Kyiv, which will take place on March 26. Nana will make a presentation “Brain and emotions. How to preserve health and fight stress”.