Those who are depressed tend to hold negative beliefs about themselves. According to cognitive models of depression, these beliefs are often out of line with reality. For example, someone with depression might think, “No one really cares about me,” even if they have friends or family members who clearly do.
People with depression also tend to make overly negative predictions about how things will turn out. They assume social interactions will be awkward, job interviews won’t lead to offers, and romantic overtures will lead to rejection.
Researchers have suggested that depressed individuals struggle with “belief updating” in the face of positive feedback. In other words, someone who is depressed might expect a job interview to go badly because they don’t believe they’re competent. And if they’re offered the job, they might tell themselves, “I guess I really fooled the interviewer.” In other words, they fail to use the positive outcome to update their beliefs about their own competence. New research published in the journal Clinical Psychological Science examined whether those with symptoms of depression might view positive feedback about their own performance as less valid, preventing them from using this information to positively update beliefs about their abilities.
This new research focused on a phenomenon called “cognitive immunization.” Just as a vaccine can make your body less “open” to infection, cognitive immunization can make your beliefs less open to change. The problem is that while we want our bodies to shut down infections, we don’t want our brains to shut down new evidence.
Imagine two different characters. Sad Sam struggles with depression; Content Chris does not. Sam and Chris both decide they want to learn computer programming and so they sign up for a coding course. Both Sam and Chris do well on the first assignment and get this feedback from the professor: Excellent work on your exam! You really seem to have a talent for writing code.
What kinds of thoughts will Sam and Chris have in response to this feedback? According to the cognitive immunization approach, it might look something like this.
- Chris: Cool. I guess I’m better at this than I thought I would be. Maybe I should look into taking more computer science courses.
- Sam: I guess that assignment was really easy if I did that well. Or probably the professor is just being encouraging and tells everyone they did well.
What’s happening here? Chris is integrating the positive feedback into his sense of his own abilities. Sam decides the positive feedback can’t possibly be valid, so it doesn’t really change her views of her own abilities.
For this new research, the authors recruited individuals with a wide range of scores on the Beck Depression Inventory, a common self-report measure of depression. Research participants were told the study would require them to take a test that was very difficult and designed “to be solved correctly by only a few people.”
Before taking this difficult test, participants first predicted how well they would do, responding to questions like, “I will be successful in working on the tasks from the test.” After taking the test, the participants received feedback about their scores.
Here’s where it gets interesting: Participants were randomly assigned to receive one of three types of phony feedback – regardless of how they had actually performed. In one condition, participants were told they scored among the top 50% of all participants; in the second condition, participants were told they were among the top 10%; in the third condition, participants were told they were among the top 1% of scorers. After this feedback, participants completed a measure designed to tap into “cognitive immunization.” In this measure, participants indicated whether they trusted the feedback they got on their performance, and whether they thought their performance on the test was an exception to how well they would generally do. Finally, participants indicated how well they thought they would do on such tasks in the future.
As expected, compared to people with low levels of depression symptoms, people with depression generally thought they wouldn’t perform as well on the difficult test. If we stick with our example from above, the researchers basically found that someone like Sam would be inclined to think, “If it’s a really hard test, I probably won’t do very well.”
But what happened when participants got positive feedback on their performance? The results of the study showed that participants with higher scores on the depression inventory believed the feedback just as much as those with low depression scores. But participants with higher levels of depression engaged in more cognitive immunization. In particular, they didn’t generalize positive feedback on their test performance to what might happen in the future. Instead, they assumed their positive performance on the task was just an exception. To go back to our example, Chris might think, “Well, I did well on this test, so I guess I’m pretty good at difficult tasks.” But Sam would be more likely to think, “I did well on this specific thing, but that’s just a fluke because I’m pretty bad at difficult things in general.”
In sum, what this study suggests is that people who are depressed might believe positive feedback, even when it’s surprising. But they may struggle to generalize that feedback, instead believing that when they perform well at something, it’s an exception to the rule. For example, if you’re depressed and someone says to you, “It was so great meeting you! I had a such a good time,” it’s not that you won’t believe them. It’s that this positive feedback won’t do much to change your view of how your social interactions will generally go in the future. This research suggests a possible cognitive “target” for therapists working to treat those with depression: helping to generalize from specific pieces of positive feedback to more general expectations about future events.