A mood disorder can affect a person's everyday emotional state and interfere with relationships or activities at work or school. Depression and bipolar disorder are examples of mood disorders.

Depression is a serious medical illness that affects more than 20 million Americans. Symptoms, that are persistent and interfere with daily life, can include:

  • Sadness or loss of interest or pleasure in activities the person used to enjoy
  • Weight loss
  • Difficulty sleeping or oversleeping
  • Energy loss
  • Feelings of worthlessness
  • Thoughts of death or suicide

Depression may be linked to a variety of causes, including genetic, environmental, psychological and biochemical factors. Depression usually starts in the late teens or 20s. It is more common in women, who face unique emotional experiences across the lifespan (See Women's Behavioral Health). Women may be affected by postpartum depression after the birth of a baby. Some people experience seasonal affective disorder in the winter. Depression is one part of bipolar disorder.

Treatment can include therapy, medications and electroconvulsive treatment (ECT) or transcranial magnetic stimulation (TMS).

Bipolar disorder is a serious mental illness marked by unusual mood changes. People with bipolar disorder fluctuate from mania (happy, active periods) to depression (down periods). They often have normal moods in between. Causes of bipolar disorder may not be known and the condition may have roots in family genetics and abnormal brain structure. Symptoms typically appear in late teen to early adult years. The disorder usually lasts throughout a person’s life.

Treatments include medication and therapy. Without treatment, bipolar disorder can affect relationships, lead to school or job problems and even contribute to suicide.

Learn more about brain and spine neurological conditions at The Ohio State University Wexner Medical Center.