It is well-established that depression is associated with negative beliefs about one’s self, other people, and the world. For example, someone with depression may hold a belief such as I’m a failure, or People cannot be trusted, or The world is unjust. But recent research is providing a more nuanced understanding of this phenomenon – one that could help inform the treatment of depression. Specifically, the problem is not simply that the content of someone’s beliefs is negative in depression; it’s also that there is an inability to abandon these beliefs. Most people develop negative beliefs sometimes (eg, I’m bad at this), but typically revise such beliefs if they receive positive feedback that contradicts them, such as being told that they did well at a challenging task. People with depression, however, often stick to negative beliefs despite having positive, disconfirming experiences.
This is exemplified by a male patient in his 30s whom I encountered at the beginning of my career in clinical research, when I was a student research assistant. This patient held the belief that he was unlikeable. To challenge that belief, his therapist conducted a role-play exercise in which the patient had a conversation with an unfamiliar person – me. Without knowing anything about this patient, his problems or the therapist’s goal for this specific session, I truly enjoyed my conversation with this man, who was very friendly and asked interesting questions.
Afterwards, I truthfully explained that I’d enjoyed speaking with him and would be interested in getting to know him further. The patient, however, expressed that he didn’t believe what I was telling him and suspected that the therapist had instructed me to be nice to him. He explained that, in his experience, when people showed an unusual interest in him, they were not honestly interested in him but had hidden agendas. So, he disregarded the honest, positive feedback and maintained his view that nobody liked him.
Motivated by this therapeutic setback, I set out to investigate whether the propensity to dismiss positive information is typical of people with depression. To this end, my colleagues and I used the methodology of a research area known as ‘belief updating’, in which researchers examine how people adjust their beliefs in response to new information. Findings from our research indicate that people with depression have more difficulty than mentally healthy people do with updating negative expectations about their performance (on a task administered by experimenters) in response to positive feedback. Similar approaches by other research groups, examining how people interpret ambiguous social situations (such as being called into a boss’s office), suggest that, once a negative interpretation of a situation is established (eg, I am going to be fired), people with elevated depressive symptoms have difficulty revising that interpretation – even if a positive interpretation turns out to be more plausible in the end.
People with depression may also end up with more negative beliefs, in part because they actively seek out information that suggests or confirms their negative views. This notion is consistent with recent theories about how the brain encodes new information. The ‘Bayesian brain’ framework suggests that the brain seeks to corroborate evidence for its predictions and to minimise prediction errors. Applying this framework to depression, my colleagues and I have proposed that people with depression intensively engage with information that seems to confirm their negative self-views, while avoiding situations in which they could encounter positive prediction errors – eg, by declining an invitation to a party at which other people might have been friendlier to them than they had predicted. When confronted with unexpected positive information, they give it little weight and rely more heavily on their prior beliefs.
Several other mechanisms could help account for the persistence of negative beliefs in depression. Our research has shown that people with depression tend to negatively re-interpret the positive information they receive. For example, someone might question the credibility of the information, as demonstrated by the patient who didn’t believe that I had enjoyed our conversation. Or, one might consider positive information to be an exception rather than the rule (eg, by thinking, It was just lucky that I did not fail for once). This propensity to devalue the evidence against one’s expectations, which my colleagues and I call ‘cognitive immunisation’, can make people’s beliefs immune to the influence of new, positive experiences.
Of course, people with depression also frequently experience negative emotions such as sadness – and there is evidence that such emotions can hinder belief-updating. That is, when they are sad, people are less likely to use positive information to adjust their negative beliefs. The maintenance of negative beliefs, in turn, seems to be related to having less positive emotional states. People with depression may become trapped in a self-reinforcing feedback loop of negative beliefs and emotions.
Importantly, the negative beliefs of people with depression often do not align with their actual experiences. For instance, research has shown that people with depression consistently underestimate their cognitive abilities, whereas mentally healthy people typically overestimate them. Similarly, while people with depression do tend to experience more negative emotions than others, when assessing daily mood, research has found that individuals with depression experience more happiness and less sadness than they previously predicted they would.
Often, then, the negative beliefs of people with depression neither accurately reflect reality nor offer any clear hedonic benefit. On the contrary, these beliefs are usually accompanied by unpleasant emotions. To understand why people with depression have difficulty revising beliefs that make them feel low, it is important to determine what value negative beliefs might have for them.
Based on my clinical work on the treatment of depression, I suggest that many people with depression are trying to protect themselves from future disappointments. More specifically, many of those with depression have had previous experiences – a perceived failure, for instance – in which they saw their negative beliefs as being proven ‘correct’. As such (rare) experiences were associated with disappointment and unpleasant emotions, people with depression may regard them as highly significant and try to avoid the recurrence of such disappointments at all costs. Consequently, adopting a ‘better safe than sorry’ approach, they might (consciously or unconsciously) prefer to hold on to negative beliefs rather than revise them, because a revision of the beliefs carries the risk of renewed disappointment if things turn out badly after all.
In addition to providing insight into the psychopathology of depression, the research on belief-updating offers implications for treatment – suggesting that an important therapeutic goal should be to help individuals integrate novel positive information into their beliefs. To achieve this, it will likely be helpful to try to ensure that patients are not acutely sad or upset when they receive new positive feedback – otherwise, it is likely to be disregarded. There are many potential ways to alleviate acute sadness, from viewing funny film clips or listening to music, to recounting a happy personal memory. Returning to the example of the patient I spoke with, it might have been helpful if the therapist had sought to lift the patient’s mood before asking him to have a conversation with me – or before engaging in other exercises aimed at revising his negative beliefs.
Therapists should also explicitly underscore the value of positive feedback for people with depression, such as by emphasising its credibility and by discussing the general conclusions that can be drawn from unexpected positive experiences. In the aforementioned example, the therapist might have explained to the patient that I was not instructed to be nice to him, because it is the goal of psychotherapy to provide people with realistic and authentic learning experiences, like those they will encounter in their everyday lives.
More fundamentally, it is important for people with depression to be aware of the inflated value that they (often implicitly) assign to their negative beliefs, as it may hinder belief-revision. While maintaining negative beliefs may seem like it provides protection from future disappointments, it also perpetuates negative feelings from day to day. It’s useful to remember that people with depression commonly underestimate their actual abilities, which suggests that the risk of being disappointed is in fact not as high as it might seem to someone with depression.
Partly as a result of their negative beliefs, many people with depression withdraw from other people and avoid activities they used to enjoy. This social withdrawal and inactivity prevent them from having experiences that could potentially challenge their negative beliefs (especially once they become more open to positive information). Therefore, it’s important that people with depression are encouraged to engage in more active behaviour. To this end, it could be helpful to refer to an important research finding: people with depression tend to overpredict the degree of effort that would be required for a potentially pleasant activity, such as going out for a walk, and underpredict how much enjoyment they would get from that activity. Accordingly, people with depression may benefit from learning that their current mood is not a good advisor in this regard, and that they should attempt to engage in potentially pleasant activities even if they do not anticipate immediate enjoyment.
For people with depression, beliefs about the self, other people, and the world are often decoupled from actual experience in a damaging way – a problem that is amplified by negative emotions and exacerbated by social withdrawal and inactivity. My hope is that, if we give more attention to the underappreciated difficulty that many people have with positively updating their beliefs, along with potential means of encouraging those shifts, more pathways will open out of the cycle of negativity.
