Depression is the leading cause of disability in the world; in the United States, close to ten percent of adults struggle with the disease. But because it's a mental illness, it can be a lot harder to understand than, say, high cholesterol. Helen M. Farrell examines the symptoms and treatments of depression, and gives some tips for how you might help a friend who is suffering. [Directed by Artrake Studio, narrated by Addison Anderson].

Helen M. Farrell: What is depression?

What is depression?

Depression, unlike fleeting sadness, demands recognition as a persistent medical disorder, challenging to diagnose and treat.

Physical manifestations in the brain, including changes in neurotransmitters and hormones, underscore depression's complexity.

Understanding depression: more than sadness, it's a clinical disorder affecting work, play, and love, resistant to mere willpower.