A new test measures analytical thinking linked to depression, fueling the idea that depression may be a form of adaptation

The researchers at McMaster University and the Centre for Addiction and Mental Health were able to show a meaningful connection between answers to their 20-question test and analytical rumination -- a type of distraction-resistant thinking that is characteristic of clinical and sub-clinical depression alike.

"Depression has long been seen as nothing but a problem," says Paul Andrews, an assistant professor of Psychology, Neuroscience & Behaviour at McMaster. "We are asking whether it may actually be a natural adaptation that the brain uses to tackle certain problems. We are seeing more evidence that depression can be a necessary and beneficial adaptation to dealing with major, complex issues that defy easy understanding."

The researches emphasize that clinical depression remains a serious mental health concern, and that understanding the underlying mechanisms at play can lead to more effective treatment. There is currently no consensus on the underlying pathology of depressive disorders, and the symptoms used for diagnosis occur on a spectrum that ranges from mild to severe.

The researchers administered their test to nearly 600 subjects. Their paper, "Measuring the bright side of being blue," appears in the peer-reviewed, open access journal PLOS ONE.

The test revealed which subjects were experiencing analytical rumination at varying levels of intensity, and found a relationship between those results and subjects who were experiencing depressive symptoms.

The research suggests that depression may be a natural condition in which the mind concentrates involuntarily on a complex issue to the point where it allocates resources to analyzing the problem at hand, diminishing concentration on other aspects of living, perhaps giving rise to disrupted eating, sleeping and social interaction that are associated with depression.

Being able to measure analytical rumination is a step toward developing new and possibly more productive ways of reducing the harmful effects of depression, the researchers say.

"We have a set of items that clinicians and researchers can use to understand how people with depression are thinking," says Skye Barbic, a post-doctoral research fellow at the Centre for Addiction and Mental Health. "Based on how people answer our questions, we can tailor appropriate levels of care and supports. This set of questions can also inform completely different discussions between the clinician and the patient. Instead of discussing the disease as a 'bad thing', clinicians may be able to help patients have insight about the potential adaptive purposes of their thinking and how this may be used as a strength to move forward in their lives."

"When working with many people who experience chronic health conditions, depression is often the limiting factor to recovery and goal attainment," says Zachary Durisko, also a post-doctoral fellow at CAMH. "The test can potentially quickly tell us when people are struggling to identify their problems, trying to set goals, or trying to move forward in their lives. We hypothesize that very different levels of support and care are required throughout these different stages of thinking."