How do you create an alpha male? From the brain. Research carried out by scientists at the Shanghai Institutes for Biological Sciences (China) with rodents has found that boosting the activity of certain brain cells can help a mouse move up the social ladder and become what we know as the ‘alpha male ‘. This is stated in the conclusions of the research collected by the journal Science.
Like men flexing and flashing their muscles in a pulse or flaunting their driving skills in a sports car race, male mice compete to establish a social hierarchy. When each mouse knows its place, there is less long-term social conflict.
In fact, individuals of many species of the animal kingdom regularly compete with each other to establish this hierarchical order in the community , in which the phenomenon known as the ‘winning effect’ also occurs, where victories increase the chances of achieving another success. in the next episode of social dominance.
The birth of an alpha male takes place in a neural circuit of the brain
Rodent experiments showed that l as nerve cells in a region called the dorsomedial prefrontal cortex appear to control the fact that male mice are dominant or submissive to other males of their own species. Thus, the stimulation of this subset of neurons increased up to 90% the chances that a mouse would become the winner in an aggressive confrontation with other rodents.
The neural circuitry of the brain of the mice that turned out to play a key role in the domination process clearly showed that its stimulation significantly increased the expectations of being the winner in an aggressive confrontation without affecting the level of anxiety or their motor performance.
In order to understand this mechanism, the scientists subjected the animals to a standard test of social dominance: They put the mice head-to-head in a plastic tube too narrow for the animals to pass through at once. With no way to get ahead, the lower-ranking mouse had to back away, pushed out of the tube by the more dominant mouse. The rodents clashed inside the tube while the experts recorded their pushing, recoil, resistance, retreat or calm behavior.
By inhibiting the brain cells that the experiment focused on, they caused a reduction in defensive responses and increased withdrawals. However, by stimulating these same neurons using optogenetics, they had just the opposite effect. If those mice won enough times in a day, they maintained their status for two to three days.
Other studies have also suggested a critical role for the prefrontal cortex in controlling social dynamics in various species, including humans, but this new study adds new details allowing researchers to trace how that neural ‘fire’ influences the behavior immediately and continues to persist over time.
However, other factors, such as the size of the animal, can also influence its ability to win a fight. But, according to the authors, persistence is key: “In risk tests, the important thing is how much effort you want to put into that competition,” says Hailan Hu, co-author of the work.
Although the results in mice do not directly translate to humans, other p ermiten study the neurobiology of dominance behavior in detail levels are not possible in human subjects (as with the use of optogenetic).
Reference: T. Zhou et al. “History of winning remodels thalamo-PFC circuit to reinforce social dominance”. Science, July 13, 2017. doi / 10.1126 / science.aak9726
