Which disorder is characterized by experiencing both manic and depressed states?

Bipolar disorder is characterized by the presence of both manic and depressive states, which are distinct phases that can vary in duration and intensity. During manic episodes, individuals experience heightened energy, euphoria, or irritability, often engaging in risky behaviors. In contrast, depressive episodes are marked by feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. The fluctuations between these two states are a defining feature of bipolar disorder, making it unique among psychological disorders.

In the context of the other options, generalized anxiety disorder primarily involves excessive worry and anxiety without the distinct mood elevation associated with mania or the deep lows of depression. Major depression specifically focuses on the depressive phase and does not encompass manic experiences. Dissociative identity disorder involves the presence of two or more distinct personality states and does not relate to mood swings or the cycling between manic and depressive states.