For decades, depression has been understood and treated as a disorder defined primarily by sadness. But to many people, the more profound burden is not feeling badly, but not feeling much of anything at all.

This emotional flatness, known as anhedonia, affects nearly 90 percent of individuals with major depression and it is increasingly recognized as a critical driver of poor outcomes.

Directly targeting this loss of positive emotion may offer a more effective path to recovery, according to a study by researchers at Southern Methodist University (SMU) and the University of California, Los Angeles (UCLA).

PAT is designed to restore the brain's capacity to experience pleasure, motivation and meaning.

The study points to a shift in how clinicians might think about treating depression and anxiety: Not working to dampen distress alone, but by actively rebuilding a patient's capacity to feel joy.

At the heart of the research is a therapeutic approach called Positive Affect Treatment (PAT), a structured, 15-session program developed over more than a decade of clinical trials. Unlike traditional therapies, which focus on reducing negative emotions, such as sadness, worry or fear, PAT is designed to restore the brain's capacity to experience pleasure, motivation and meaning.

To test the effectiveness of the approach, researchers, led by Alicia E. Meuret, PhD, a professor of psychology at SMU and director of the Anxiety and Depression Research Center, along with Thomas Ritz, PhD, also of SMU and UCLA's Michele G. Craske, PhD, conducted a randomized controlled trial involving 96 adults diagnosed with severe anhedonia, depression and anxiety.

Participants were assigned either to PAT or to a more conventional therapy that targeted negative emotional states. Over the course of treatment, researchers used a set of nine reward-related measures, such as anticipation and enjoyment of positive experiences, to track changes in their outlooks.

The results were notable. Patients receiving PAT showed greater overall clinical improvement than those in the comparison group, and these gains held at a one-month follow-up. Importantly, participants in the PAT group not only reported increased positive emotions, but also experienced reductions in depression and anxiety symptoms, even though those symptoms were never directly targeted.

This dual benefit underscores a key insight: restoring positive emotional functioning may indirectly ease negative states. As the researchers concluded, impaired processing is a central mechanism in depression and anxiety, contributing to risks such as relapse and suicidality.

Meuret offers a vivid way to understand the distinction. “There's a difference in feeling helpless and feeling hopeless,” she explained in a press release. “When you feel helpless, you still have the drive and the will to want to change things. When people feel hopeless, they don't believe anything will change. That's what anhedonia can look like, and taking away negative emotions doesn't fix it.”

PAT works by targeting the brain's reward system, the network that governs how we anticipate experience, and learn from positive events.

Participants reported increased positive emotions and reductions in symptoms of depression and anxiety.

Through guided exercise, patients are encouraged to re-engage with pleasurable activities, shift attention toward positive experiences and cultivate practices such as gratitude, savoring and loving-kindness. These are not simply feel-good add-ons, they are structured interventions aimed at retraining neural pathways involved in reward.

For years, both medication and psychotherapy have prioritized symptom reduction, meaning less sadness and less anxiety. But patients themselves often report that what they want most is the return of positive feeling, a sense of purpose, connection or simple enjoyment.

This study suggests that those goals may not be secondary at all; they may be central to recovery.

In reframing depression as not just a disorder of distress, but also one of diminished reward, the research opens the door to more nuanced, and potentially more effective treatment strategies. For patients who feel stuck in a gray emotional landscape, that shift may make all the difference.

The study is published in JAMA Network Open.