We tend to think that if someone is depressed, they will feel sad or down most of the time. But what many don’t realize is that these are not the only symptoms of depression. Another common symptom of depression that is sometimes overlooked is the feeling that the things we once liked are no longer interesting or enjoyable.
Known as anhedonia, this symptom is present in up to 75% of adults and youth with depression. But despite how common this symptom is, it is still one of the most difficult to treat and manage.
Anhedonia is defined as reduced interest or pleasure in all—or nearly all—activities a person previously enjoyed. If a person experiences anhedonia for a long period of time (at least two weeks in a row), they may be diagnosed with depression, even if they don’t feel sad or down.
Although it is primarily associated with depression, anhedonia can also be a symptom of other disorders, such as schizophrenia, anxiety, and Parkinson’s disease.
In in-depth interviews that my colleagues and I conducted with young people about depression, many described anhedonia as not only a loss of joy, but also decreased motivation to do things. For some, this lack of motivation was only related to specific things, like going to school or seeing friends. But for others it was more serious and they felt that they did not want to do anything at all, not even live.
But as worrisome as anhedonia can be, it’s usually not the main goal of depression treatment.
It is recommended that cases of mild depression be treated with talk therapy. People with more moderate or severe cases of depression may be prescribed antidepressants. Although all of these treatments claim to help patients cope with and overcome symptoms, more than half of people with depression do not respond to the first recommended treatment. Even after switching treatment, approximately 30% of patients continue to experience symptoms.
It has been argued that one reason for these low response rates may be that current treatment techniques do not adequately address anhedonia. Research also shows that having anhedonia predicts chronic relapses of depression. It is even possible that some antidepressant treatments make anhedonia worse.
What is this about? One possibility is that the error is that current standard treatments focus primarily on treating depressed mood and the brain processes that underpin low mood, but not anhedonia. For example, the main goal of talk therapies, such as cognitive behavioral therapy, is to reduce negative thinking in patients. The most common antidepressants also act primarily on serotonin, which is believed to partly underpin the way the brain processes negative information.
But because anhedonia reduces the joie de vivre, treatments like behavioral activation (a form of talk therapy) might be better at combating it. It should not be forgotten that behavioral activation is intended to help people with depression to take simple and practical steps to enjoy life again. However, there are also studies that suggest that behavioral activation is no better than [standard treatments] for treating anhedonia. Probably because the very nature of anhedonia includes a lack of motivation, making it difficult for patients to engage in any therapy, even in ways that could most benefit them.
Anhedonia has also been linked to dysfunctional reward mechanisms in the brain. Therefore, treatments that focus more on improving the way the brain processes reward could help alleviate it.
The bad thing is that the reward system of the brain is not simple at all. It actually involves several threads, such as anticipation, motivation, pleasure, and learning about the reward. Problems with any of these threads could be contributing to the anhedonia. hence the importance of discovering how these threads work.
Although anhedonia can be complex, that doesn’t mean there is no hope for those who suffer from it.
For example, research shows that talk therapies that focus on reward processing may help reduce reward. A recent pilot study also found that a new type of talk therapy called augmented depression therapy may work better than cognitive behavioral therapy in treating depression. This is because augmented depression therapy specifically targets anhedonia by having patients focus on both their negative and positive experiences.
Furthermore, antidepressants that target neurotransmitters involved in the reward system (such as dopamine) might be more suitable for patients with anhedonia. In fact, there are already studies that show that one of them, ketamine, could be promising.
And while it can be difficult to find motivation if you’re experiencing anhedonia, trying to find time for fun and enjoyable activities or experiences, such as a hobby you used to enjoy, or even a new hobby, may help alleviate anhedonia.
Article originally published on The Conversation. Ciara McCabe is Professor of Neuroscience, Psycholopharmacology and Mental Health at the University of Reading.
