What Is Neurogenesis?

There is a fairly widespread belief that neurons are only created in our childhood. However, this claim is false. The concept of neurogenesis can be explained in a few words: the birth of new cells. This phenomenon represents a key aspect in neuronal plasticity and in processes as important as learning and memory. Without a doubt, it is a fundamental finding that is currently being exhaustively investigated by the scientific community due to the great benefit it can bring.

Neurogenesis was not confirmed until relatively recently. In the 1960s, Altman and Das (1965) demonstrated this phenomenon in rodents, but it was not until 1998 that Peter S. Eriksson’s research team demonstrated it in humans. Conclusions from subsequent research (for example, Moreno R., Pedraza C. and Gallo M. 2013) show that we generate new cells during our adulthood and that it is vitally important to promote their creation. Do you want to know what it is and how we can benefit from it? Join me!

Where does neurogenesis occur? 

This phenomenon occurs in the subventricular area (lower part of the lateral ventricles), but especially in the subgranular area of ​​the dentate gyrus of the hippocampus  (Ehnenger and Kempermann, 2007). This structure is located in the temporal lobe and is part of the limbic system. Among the main functions of the hippocampus we find those related to memory, learning, spatial orientation and emotional regulation.

The new cells can be classified into two groups. On the one hand, we find stem or stem cells with the capacity to divide indefinitely and that differentiate into different types of specialized cells. On the other hand, we find neuronal progenitor cells, whose capacity for expansion and self-renewal is more limited than the former (Arias-Carrión, 2007).

Why is neurogenesis so important?

According to Couillard-Després et al. (2011), “ there is a facilitating relationship between adult hippocampal neurogenesis and the performance of hippocampal-dependent learning and memory tasks during aging” . This statement highlights the importance of learning and memory tasks for the creation of new neurons. Or what is the same, if we want to create new cells throughout our lives, we must not neglect activities that stimulate our brain.

Learning something new not only means acquiring a new skill, but creating neural material. Speaking a new language, playing an instrument, or any activity that keeps your mind active will encourage the creation of new neurons. And we can do this throughout our lives. For this reason, it is never too late to learn, on the contrary, we will slow down the natural cognitive decline produced by age.

However, sedentary lifestyle and inactivity have the opposite effect, not only do they not favor neurogenesis, but they also contribute to the cognitive deterioration running its course without restraint. Contrary to popular belief, what harms neurons is not excessive activity, but rather inactivity. Alcohol, tobacco, poor sleep, and an unbalanced diet destroy them directly.

More sport and less stress!

Until now we knew that sport reduced stress and put us in shape, but not only that, now we know that it also favors neurogenesis. Morales-Mira M. and Valenzuela-Harrington M. (2014) state that “ physical exercise effectively increases neurogenesis in the adult hippocampus, which is related to improvements in tasks dependent on it, constituting a great therapeutic potential in the delay and repair of brain damage caused by injury or disease ” .

When we are stressed or suffer from chronic stress, the hypothalamus secretes hormones that activate the pituitary gland facilitating the release of glucocorticoids (cortisol).  If we are unable to cut off this torrent of cortisol in the body, it will eventually affect the neurons of the hippocampus and thus neurogenesis would not occur.

When performing physical exercise, we regulate glucocorticoid levels and deactivate the brain circuit that causes us stress and thus facilitate the regeneration of the hippocampus. In summary, a stressed hippocampus does not produce neurogenesis; a healthy hippocampus, yes.

If we want to maintain a healthy mind that continues to generate new cells throughout our lives, it is as simple as activating the mind. We no longer have arguments to sit still in natural decay, but we  know that we have the potential to promote neurogenesis and maintain a more active mind for longer than we thought.

Read, learn to play the guitar, the piano, sign up for Chinese classes, go for a walk, meditate, exercise… there is no excuse, get your mind in shape!