How do humans learn to flirt and choose mates when they hit puberty? According to a new study, it is because of the addition of new brain cells. It was earlier believed that humans and animals were born with a full set of brain cells. However, in the recent past, it has been found that new brain cells are born in adult humans and animals in two regions of the brain—those connected with memory and smell.
According to a new study, published in Proceedings of the National Academy of Sciences, new brain cells are added during puberty that help them interpret body language and facial expressions. These new cells help mammals pick up social cues and successfully woo sexual partners.
The research, which studied hamsters, was conducted by two neuroscientists from Michigan State University in the US. According to the researchers, they picked up the subject because of findings a few years ago that new brain cells are added in mammals during puberty in the amygdala region of the brain. It was however never known if these cells survived for long. The amygdala is associated with the function of picking up social cues (humans use it to analyse facial expressions and body language, and hamsters to pick up signals transmitted by smell). The researchers conducted their study to find out if these new brain cells were playing any part in helping mammals find mates.
They injected male hamsters with a chemical marker that showed cell creation. The researchers allowed them to interact and mate with female hamsters when they matured into adults. After their sexual encounters, when the researchers examined their brains, they found that new cells had been added to the amygdala. Many of them in fact contained a protein linked to social and sexual behaviour. The researchers found that more of these new brain cells survived if the males were raised in a better environment. For instance, bigger cages with wheels and nesting materials, as opposed to smaller and empty cages. Because the amygdala plays a similar role in both humans and hamsters, the researchers argue that humans also use these new cells to find potential mates.