Depression may be 'contagious'

A particular style of thinking that makes people vulnerable to depression can actually "rub off" on others, a new study has claimed.
The study, by psychological scientists Gerald Haeffel and Jennifer Hames of the University of Notre Dame shows that people who respond negatively to stressful life events, interpreting the events as the result of factors they can't change and as a reflection of their own deficiency, are more vulnerable to depression.
This "cognitive vulnerability" is such a potent risk factor for depression that it can be used to predict which individuals are likely to experience a depressive episode in the future, even if they have never had a depression before.

The researchers hypothesised that cognitive vulnerability might be "contagious" during major life transitions, when our social environments are in flux.
They tested their hypothesis using data from 103 randomly assigned roommate pairs, all of whom had just started college as freshmen.
Within one month of arriving on campus, the roommates completed an online questionnaire that included measures of cognitive vulnerability and depressive symptoms.

The results revealed that freshmen who were randomly assigned to a roommate with high levels of cognitive vulnerability were likely to "catch" their roommate's cognitive style and develop higher levels of vulnerability.
Those assigned to roommates who had low initial levels of cognitive vulnerability experienced decreases in their own levels.

The contagion effect was evident at both the three-month and six-month assessments.
Students who showed an increase in cognitive vulnerability in the first three months of college had nearly twice the level of depressive symptoms at six months than those who did not show such an increase.
Based on these findings, researchers suggest that the contagion effect might be harnessed to help treat symptoms of depression.
"Our findings suggest that it may be possible to use an individual's social environment as part of the intervention process, either as a supplement to existing cognitive interventions or possibly as a stand-alone intervention," researchers said.

The study was published in Clinical Psychological Science, a journal of the Association for Psychological Science.