Puberty shapes our ability to recognise and remember faces as we grow into adults, according to a new study that may explain how adolescents begin to think about each other as romantic partners for the first time.
Faces are as unique as fingerprints and can show a great deal of information about our health, personalities, age and feelings. Scientists at Pennsylvania State University in the US have discovered that adolescents begin to view faces differently as they prepare for the transition to adulthood.
"We know that faces convey a lot of different social information, and the ability to perceive and interpret this information changes through development," Suzy Scherf, assistant professor at Penn State. "For the first time, we've been able to show how puberty, not age, shapes our ability to recognise faces as we grow into adults," said Scherf.
The ability of adolescents to retune their face processing system, from showing a bias toward adult female faces as children, to preferring peer faces that match their own developmental stage in puberty, is part of the social metamorphosis that prepares them to take on adult social roles, researchers said.
They recruited 116 adolescents and young adults for the study and separated them into four pubertal groups depending on their stage of puberty. Researchers determined the adolescents' stage of development through self-assessments as well as parent-provided assessments. The researchers presented participants with 120 grey-scale photographs of male and female faces.
The pubertal status of the faces in the pictures matched that of the participants. Participants were asked to look at faces from all four pubertal groups, and the researchers measured their face-recognition ability using a computerised game. After studying 10 target faces with neutral expressions, participants were shown another set of 20 faces with happy expressions and had to identify whether they had seen each face previously or if they were new. Researchers found that the pre-pubescent children had a bias to remember adult faces.
"This is interesting because these are school-age children who spend lots of time with other children, yet they are still biased to remember adult faces," said Scherf. In contrast, adolescents had a bias to remember other adolescent faces. Among adolescents who were the same age, those who were less mature in pubertal development had better recognition memory for similarly less mature adolescents.
"This may explain a well-known finding that adolescents organise their peer groups according to pubertal status and is relevant for understanding how adolescents begin to think about each other as romantic partners for the first time," Scherf said. The study was published in the journal Psychological Science.