A recent UCSD study has linked drug use among teenagers to their involvement in social networks, their sleeping patterns and their proximity to individuals with similar habits.

Assistant professor of psychiatry Sara Mednick used information from an online database called the National Longitudinal Study of Adolescent Health to determine whether teenagers who have friends with poor sleep patterns are likely to adopt similar habits. Furthermore, it was found that irregular sleeping habits oftentimes lead to increased marijuana use.

Mednick — along with Harvard sociology professor Nicholas Christakis and UCSD political-science professor James Fowler — examined social behavior within the networks of more than 8,000 students from the seventh to 12th grade. Participants were asked to answer surveys that included questions about their sleep patterns and drug use.

The students were also asked to give the names of five male and five female friends, who were in turn asked to fill out the same survey and name their friends — effectively creating a network. Participants retook the surveys three additional times, at intervals of three years.

“We were able to track how these behaviors that kids were having the first year changed across the years, and how the effect of new friends also affected their behavior,” Mednick said. “So, if I knew you as a friend and you started smoking pot, [we analyzed] how likely it would be that I would start smoking pot.”

Using this data, researchers found that collective drug-and-sleep behaviors extended to four degrees of separation in social networks.

According to the study, if a member of an individual’s given network sleeps less than seven hours, the likelihood of the original individual sleeping less than seven hours is increased by 11 percent. Additionally, Mednick found if a participant reported using marijuana, his or her friend would be 10 percent more likely to use the drug as well.

The study also concluded that a participant’s tendency to use drugs increases by 19 percent if they have a friend who sleeps less than seven hours a night. Though the correlation was more dramatic between individuals who were direct friends, participants were 5 percent more likely to use drugs if an acquaintance within four degrees did so as well.

Mednick said her discoveries can be explained by a strong social influence among teenagers. For example, if you have a friend who rarely sleeps, you — through spending time with your friend — will probably adopt similar habits.

“In order to have my sleep affect your sleep, we’ve got to be physically involved with each other,” Mednick said. “It’s a more influential aspect — a more direct aspect. That way, we can actually hang out together, not sleep together and maybe even do drugs together. These are the social aspects of a strong influence.”

Mednick said she will continue her research by examining the effects of napping within a network.

Readers can contact Victoria Bañuelos at [email protected].