Mood disorders involve persistent disturbances in emotional states that affect daily functioning. The most common types include:

• Major Depressive Disorder (MDD): Characterized by prolonged sadness, loss of interest in activities, fatigue, sleep disturbances, and difficulty concentrating.
• Bipolar Disorder: Alternates between episodes of extreme highs (mania) and severe lows (depression). Manic episodes involve heightened energy, impulsivity, and sometimes delusions, while depressive episodes resemble major depression.
  Persistent Depressive
• Disorder (Dysthymia): A chronic form of depression with milder but long-lasting symptoms.