Depression, particularly recurrent depression, has pretty significant effects on how we perceive the world and how well we make plans for the future.
In an article published in Biological Psychiatry in March 2020, Tobias Kube and co-authors develop a model of how depression affects critical cognitive processes that expands and extends the traditional model of cognitive changes associated with depression developed by Aaron Beck.
It is well established that people with depression are more likely to expect negative events and also have a lower rating of their ability to cope with a challenge.
In addition to different perceptions, there are differences in cognitive processes. Depression affects the ability to change expectations for the future in response to new information.
Imagine you are thinking about an upcoming performance evaluation. It would not be surprising to worry that you are going to get a negative review. But after you meet your boss, if you are depressed, receiving an unexpected good review often doesn’t seem to change how you think about the future very much.
This failure to change means that the negative expectations that are common when you are depressed are very resistant to disconfirmation.
How likely you are to change your view of the future when you get good news depends on how confident you are about the initial judgment.
You don’t just think, “I am 90% sure that I will get a bad review.” You think either, “I am 30-95% sure I will get a bad review,” or “I am 85-95% sure I will get a negative review.” In the first case, you are pretty open to changing your view if you get unexpected news. In the second case, you will tend to look for other explanations… “That review was a fluke” or “That is not what my boss really feels.”
People with depression are not only more negative, they are more confident in their negativity.
Because changing negative expectations is hard, especially for people with chronic depression, psychotherapies that work have to be thoughtfully developed. It most definitely is not enough to say, “that is not logical.” That is why we like the Cognitive Behavioral Analysis System of Psychotherapy.
Distorted Cognitive Processes in Major Depression: A Predictive Processing Perspective. Kube, Tobias et al.Biological Psychiatry, Volume 87, Issue 5, 388 – 398