Where do “chemical imbalance” beliefs come from? Evaluating the impact of different sources

Introduction: Although the etiology of depression is incredibly complex, the narrative that it is caused by a simple "chemical imbalance" persists in lay settings. We sought to understand where people are exposed to this explanation (i.e., the "source"), and the relative influence of each source. Methods: A total of 1,219 college students were asked where they had heard of the chemical imbalance explanation and how much they believed this to be true. Independent raters coded open-ended responses and we used self-report measures to capture chemical imbalance belief endorsement. Results: The most common sources of exposure to this explanation were the classroom, the Internet/media, other people (e.g., friends), and healthcare providers. In a regression analysis, only learning about the chemical imbalance explanation from healthcare providers uniquely predicted the adoption of the chemical imbalance belief. The correlation held even after controlling for depression symptoms, a family history of depression, and having had a diagnosis or treatment of mental health disorder (all of which also uniquely predicted chemical imbalance belief endorsement). Discussion: These results suggest that healthcare providers play an important role in the dissemination of the chemical imbalance message, which is an oversimplified, scientifically controversial, and potentially treatment-interfering narrative. Interventions directed at healthcare providers may help them engage with more accurate messages.