Contrary to popular belief, there has been an increase in extraversion and self-esteem among American teenagers, which suggests loneliness is decreasing, according to a recent study.

There has been a growing concern that modern society is increasingly lonely. In 2006, a New York Times article "The Lonely American Just Got a Bit Lonelier" highlighted research that shows a decline in social engagement--people are less likely to join clubs, have fewer close friends, and are less likely to perceive others as trustworthy.

Researchers from the University of Queensland and Griffith University conducted an analysis of data on high school and college students. They found that there has been a modest decline in loneliness over time. Female students reported lower loneliness than male college students.

"The trend in loneliness may be caused by modernization," said David Clark, lead author of the study.

Throughout history, modernization has changed the way people interact with one another.

"People become less dependent on their families and need more specialized skills, which could lead to less interest in social support and more self-sufficiency," Clark added. "Over time, people are more individualistic, more extroverted, and have higher self-esteem."

In the first study, the researchers examined past studies that utilized the Revised UCLA loneliness scale (R-UCLA) to analyze changes in loneliness over time, and gender differences in loneliness. The studies focused on college students through the year 1978 to 2009. Analysis of the studies showed a modest decline in loneliness over time. Female students reported lower loneliness than male college students.

The first study used a small sample of studies, which limits the reliability of the analysis. The literature also focused on college students, which is not necessarily a representative sample of the general population. The second study aimed to address these limitations.

In the second study, Study 2 utilized a large representative sample of high school students from the Monitoring the Future (MTF) project. The MTF project surveyed the behaviors, attitudes and values of American high school students. Overall, high school students reported a decline in loneliness from 1991 to 2012.

The researchers examined specific items within the MTF data to determine if various aspects of loneliness demonstrated differing trends. The MTF project assessed feeling lonely, feeling left out, and desiring more close friends, which assess subjective feelings of isolation; the researchers termed this factor "subjective isolation." The second factor included items such as whether an individual has friends to talk to, turn to, and interact with, which measures a students' social environment and social support; the researchers labeled that factor "social network isolation."

The second study found that subjective isolation declined, but social network isolation increased, which suggests that high school students perceive less loneliness but poorer social networks. High school students reported fewer friends with whom to interact, but less desire for more friends.

Clark said more research on cultures outside of the United States is necessary to determine if modernization is the root cause of the observed results.

"If other cultures show the same pattern of reduced loneliness in the face of poorer social networks, this would support the idea that modernization is responsible," Clark added.

If other cultures do not show a similar pattern, then the cause is something more specific to American culture.

The findings are detailed in the journal Personality and Social Psychology Bulletin.