杏吧原创

Babies are reassured by the presence of their mother鈥檚 scent, according to research that looked at how their brains respond to fear.

The idea that a familiar scent can soothe infants isn鈥檛 a new one. 鈥淪ome midwives tell new mums to put a worn T-shirt or scarf in the crib with their baby,鈥� says Sarah Jessen at the University of L眉beck in Germany.

To investigate whether this works, Jessen presented photos of happy and fearful facial expressions to 7-month-old babies 鈥� she says this is the age by which the fear response has developed.

Each of the 76 infants viewed the photos while being exposed to either the familiar smell of their mother, a stranger鈥檚 odour or no specific odour. Jessen also measured electrical signals in the babies鈥� brains using an EEG cap.

Before the experiment, all the babies鈥� mothers were given a cotton T-shirt, which they slept in for three consecutive nights. The mothers could use their normal shampoo, soap and deodorant but were asked to refrain from using any new products.

Seeing photographs of fearful facial expressions usually induces a fear response in babies, which produces a specific pattern of electrical activity in their brains. Those who could smell their mother didn鈥檛 have this pattern, but those who were exposed to a stranger鈥檚 odour or no specific odour did.

These results suggest a baby鈥檚 experiences, including of smell, can influence fear processing in their brain. Jessen says she is interested to investigate whether babies have a similar response to their father鈥檚 scent or to the scent of other people who they frequently spend time with.

鈥淭here isn鈥檛 much research done on odour in infancy,鈥� says Karla Holmboe at the University of Oxford. She says that work like this helps us understand how babies perceive the world and what influences their development. 鈥淚nfancy is really the foundation of everything, all the skills we learn later in life,鈥� she says.