Depression and the emotions associated with it can be contagious, according to a new study. Researchers have found that the gloomy mindset of students is vulnerable to depression which can spread, making their friends likely to suffer the condition six months later.

The research follows studies showing that people who respond negatively to stressful life events, interpreting them as the result of factors they can’t change and as a reflection of their own shortcomings are more vulnerable to depression.

The study found that those who had close contact with people suffering from depression were more likely to develop it themselves.

Doctors Gerald Haeffel and Jennifer Hames, of Indiana’s University of Notre Dame, said this vulnerability seemed to establish itself in early adolescence but can remain stable throughout adulthood.

They followed 206 room mates who had been paired up randomly, all of whom had just started their first year of university and the results revealed that students who were assigned to a room mate with high levels of cognitive vulnerability were likely to ‘catch’ their room mate’s style of thinking and develop a vulnerability to depression themselves.

The reverse was also true. Those assigned to room mates who were not prone to depression experienced decreases in their own levels of negative thinking.

The result showed that students who developed increased depressive thinking in the first three months of college, had nearly twice the level of depressive symptoms at six months than those who didn’t show such an increase.

The research was published in the journal Clinical Psychological Science.