BERLIN — During the last school year, some 18,000 young Germans began year-long adventures abroad, thrust into complete independence: suddenly, they were on their own, in a new environment, surrounded by strangers who spoke a language the students had only experienced from inside the safety of a classroom.

Psychologists from Friedrich Schiller University in Jena were wondering if such an experience could actually have lasting, positive effects on an adolescent's personality, so they analyzed the experiences of more than 700 teenagers who had participated in some sort of school exchange program and compared them with those of classmates who'd stayed ay home. The results appear in the Journal of Youth and Adolescence.

According to the study, students who spent time abroad were more open-minded, self-aware and mature than their peers who had stayed behind. In reaching this conclusion, study authors Henriette Greischel, Peter Noack and Franz Neyer took into consideration that students who chose to go abroad may also have been slightly more extroverted than their classmates to begin with.

Nevertheless, an experience in another country did appear to reinforce adolescents' receptiveness, emotional stability and intelligence: a year abroad promotes greater personal development, say the scientists.

This is particularly interesting for two reasons. First of all, personality is often said to remain pretty stable over an individual's lifetime, barring significant events such as divorce or unemployment, which may cause noticeable and lasting changes.

Secondly, there haven't been very many studies focused on what decisive factors shape personal development during puberty. The only well-established fact is that teenagers tend to wall themselves off during that time.

That's what led psychologists Christopher Soto from Colby College and Jennifer Tackett from Northwestern University to refer to early adolescence as the "the lifetime peak of meanness, laziness, and closed-mindedness." They reported that at the start of adolescence, people tend to become a lot more difficult, with their levels of conscientiousness and open-mindedness decreasing compared to that of younger children and adults.

Those who go abroad during these critical years, therefore, would benefit from a huge boost in development.

A year abroad requires teenagers to build a new social network from scratch — and friends are especially important reference points during adolescence, more so than family members. So those students who are able to come out of their shells, to feel comfortable in groups and even among strangers, ultimately have a wider circle of friends. And once they go home, they have no trouble slipping back into their previous social settings.