A new study has identified two groups of nerve cells as responsible for male mating and aggression. These brain cells send signals between the parts of the brain that control fear, anxiety, and aggression: the amygdala and hypothalamus.
The study team made this conclusion after observing that male mice struggled to have sex when signals from one group of cells in the amygdala are blocked from reaching the hypothalamus. When the signals were transmitted again, the mice were able to have sex again. Similarly, when communication between the second group of cells in the amygdala and the hypothalamus was blocked off, the mice attacked unfamiliar males half as often. But when the same group of neurons was stimulated, the rodents became unusually aggressive, attacking both male and female mice, including female mates.
The study highlights the key role of the amygdala in typical male social behaviors such as courting and aggression, and the authors hope these findings could be beneficial in developing therapies for psychological disorders characterized by excessive aggression and sexual problems.