Depression is classified as a mood disorder, but which came first: the disorder or the distressed mood? Conversely, if depression results in negative thoughts and emotions, can changing those thoughts and emotions alleviate depression?

“To some extent, the answer is yes,” says Dr. Ken Duckworth, assistant clinical professor of psychiatry at Harvard University Medical School and medical director for the National Alliance on Mental Illness, or NAMI.

Changing thought patterns is a primary goal of psychotherapy. One theory of depression known as the cognitive triad hypothesizes that negative views of oneself, the world at large and the future can be linked in a self-perpetuating cycle. Depressed individuals see themselves as helpless and worthless, and they also see the world as an especially negative and hopeless place. Therefore, they view their future as equally hopeless and impossible to improve.

[See: Am I Just Sad — or Actually Depressed?]

“If someone has a lot of negative expectations, there is a belief that things can’t work,” says Arthur Nezu, professor of psychology at Drexel University. On the other hand, someone who believes that problems are a normal part of life is better able deal with them. “How we view ourselves affects our ability to have an impact on world,” Nezu says.

Praise for Cognitive Behavioral Therapy

Changing that view is the goal of a treatment called cognitive behavioral therapy, or CBT. According to NAMI, CBT “focuses on exploring relationships among a person’s thoughts, feelings and behaviors.” A licensed therapist works with the patient “to uncover unhealthy patterns of thought and how they may be causing self-destructive behaviors and beliefs,” NAMI explains.

“The whole principle behind CBT is that your feelings follow your thoughts. If you have recurrent negative thoughts, that can make depression worse,” Duckworth says.

Of all the psychotherapies, CBT has been the best studied and validated, he says, though there are many other methods that are also proven to help patients make productive changes in thinking, such as interpersonal psychotherapy. However, changing thought patterns doesn’t always lift depression. “For some people, changing thinking alone can help, but many more need medications or other interventions plus CBT,” he says.

It’s possible for people to change their patterns of thinking on their own, at least in the earliest stages of the disease. “There is some research that shows that self-help books based on evidence-based therapies can work,” Nezu says, “but it depends on how severe and how long the depression has been. For someone mildly depressed and motivated, they probably can do it on their own.”

Duckworth recommends the book “Feeling Good” by Dr. David Burns, as does Carol Landau, a clinical professor of psychiatry and human behavior at Brown University’s Alpert Medical School. “I believe in books, and this is an excellent book about CBT, with lots of worksheets and checklists,” she says. However, she also warns that there are limits to how much anyone can self-treat. “When you get to the sobbing part, you should probably talk to someone,” she says.

[See: 11 Simple, Proven Ways to Optimize Your Mental Health.]

Therapist as “Coach”

Therapists work with patients to help them recognize their negative, self-destructive thought patterns and change them. “I would emphasize that it is not that easy to do CBT without hiring a helper,” Duckworth says. “You need a therapist to help you break it down.”

And there is more to it than “positive thinking,” Landau says. “I hate that term. If you have depression — or cancer or heart disease, for that matter — and someone says ‘think positively,’ you are blaming the victim.” Cognitive therapies are more sophisticated and complicated than that, she says. Adds Nezu: “It’s like trying to learn how to play tennis or drive a boat. You can learn on your own but it can be very helpful to take a course. A lot of therapies are very skills-based; they provide tools or skills to use. A coach can teach tennis skills, and I would teach other skills so that when you are under stress you can try to do something different.”

One such skill, Landau says, is prompting patients to put negative thoughts into context. “You go from global to individual, so instead of saying ‘my job sucks,’ you look at what happened today and how you might make it better. You scan the day and focus on one thing that was good and meaningful. You take a more realistic view of things, not just with positive thinking but with what you can control. You can’t change a pessimist to an optimist, but you can move them along the continuum.”

[See: How to Find the Best Mental Health Professional for You.]

The best therapist is one that you feel connected to, Duckworth says. “The evidence for CBT is better, but there is also some evidence that any therapist who listens to you, as long as you feel connected to them, is better than no treatment at all.” Therapists trained in CBT can be hard to find, he says, so he advises asking your clinician what type of therapy she does and, specifically, how she approaches depression. No matter what path you take, he says, “Psychotherapy is usually helpful.”

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Can You Battle Depression by Changing the Way You Think? originally appeared on usnews.com