Testosterone is a hormone that, although also present in women, appears in the collective imagination as the main substance associated with the masculine. Since its discovery, it has been related to aggressiveness, competitiveness, muscular and physical development, and sexual appetite. We know that all of this is influenced by the action of this hormone.
But… How does testosterone affect the brain? Different research helps to understand the involvement of this substance in the functioning of the male nervous system.
Testosterone is a steroid type hormone which penetrates through the cell membrane and attaches to certain proteins and passes along with them to the nucleus to be able to synthesize different proteins.
It is also one of the main sex hormones that It is part of the androgen group It is a fundamental substance for development and is involved in a large number of processes. Among them, its great importance for sexual development stands out (both the primary and secondary sexual characteristics of men depend largely on this hormone) and libido or sexual appetite.
But its functions are not only sexual, but It also has an effect on cognitive abilities, emotions, growth and bone and muscle formation and mood.
The main organs that release testosterone are the testes, which release Leydig cells along with other hormones This release is governed by the pituitary gland, located in the brain. However, the testicles are not the only organ that secretes testosterone. In fact, both men and women have testosterone (although the latter to a lesser extent). This is because some cells in the adrenal glands also synthesize and release it, and some ovarian cells in the case of women.
Although it is secreted naturally, in some individuals with different problems treatments with synthetic testosterone can be carried out This is the case of people with hypogonadism, some biological causes of erectile dysfunction or in the hormonal therapy carried out by people in the process of sex change (specifically, in those cases in which the subject seeks to reassign himself to the male sex). Patches of this hormone are also used for the treatment of osteoporosis and decreased sexual desire. They have also been used in other areas, such as sports, although their use is considered doping.
Action at the brain level
Testosterone is a hormone that acts at various levels and in different brain structures. Research reveals that specifically causes an increase in the activity of the limbic system at the brain level a set of parts of the brain that participate in creating emotions.
In this sense, it would be especially the amygdala, the hypothalamus or the periaqueductal gray matter that are affected by testosterone, which causes it to be more reactive to stimulation. It must be taken into account that these brain areas are very linked to ancestral survival mechanisms thus activating the aggressive response as a way to guarantee one’s own safety.
In addition, testosterone has different mechanisms of action by promoting and increasing the production of different neurotransmitters. Specifically, it has been observed that the secretion of dopamine and acetylcholine is greatly influenced by the level of testosterone.
Effects of testosterone on the brain
Testosterone has a series of very important effects on the brain that in turn cause different effects on the behavior and abilities of the individual. Several are specified below.
1. Increases the level of aggressiveness and competitiveness
The action of testosterone at the level of the amygdala and limbic system in general causes the subject to manifest a high reactivity to external stimuli, awakening aggressive reactions more easily. It has also been observed that as the concentration of this hormone increases, the level of competitiveness of the subjects tends to be higher.
2. It is linked to energy
The greater presence of testosterone in men is also associated with a higher level of energy and activity. This relationship is bidirectional: testosterone can make us more active, but at the same time The more active we are, the more testosterone we generate This fact means that it is recommended to exercise frequently for people who have a low level of this hormone.
3. Boosts libido
Another of the best known and visible effects of this sexual hormone is precisely the increase in libido. Both men and women. In fact, Patches of this hormone are frequently prescribed in women who have lost their sexual appetite after menopause.
4. It has an influence on mood and anxiety
By increasing the production of dopamine, testosterone has an effect on maintenance of mood and sensations of pleasure Men with low testosterone levels tend to show a greater number of depressive symptoms. Likewise, they also tend to show a higher level of anxiety than subjects with normative or high levels.
People with an excessive amount of testosterone may be less empathetic, more egocentric, and with less ability to bond emotionally This is associated with a possible inhibitory effect of this hormone with oxytocin.
6. Effect on memory
As with dopamine, testosterone causes an increase in acetylcholine levels. Being a hormone involved in brain functioning, can influence the ability to maintain information in memory and subsequently evoke it from cognitive aspects such as memory.
7. Promotes neurogenesis
Different research suggests that the presence of testosterone causes the birth and growth of new neurons, especially in the case of the hippocampus.
