The study looks at how the brain works in depressed teens aged 15-17 using fMRI, a special scan that takes pictures of the brain. It focuses on understanding how Behavioral Activation (BA) therapy helps with depression by comparing brain activity before, during, and after the therapy. BA is a treatment that helps people with low motivation by encouraging them to engage in positive activities. The study will also compare these teens with a group of healthy teens to see differences or changes. The study involves 136 participants, including 96 with depression and 40 healthy ones.

Key Points:

• The study involves five fMRI scan sessions over several weeks.
• Participants must be 15-17 years old and cannot take certain medications.
• The study requires access to technology like a smartphone or computer.

Some teens will not be able to join if they have certain medical conditions, are taking certain medications, or have a history of serious mental health issues. They will also need to complete some activities online. This study helps understand how therapy changes the brain and improves symptoms of depression.