What is a common feature of major mood disorders?

The hallmark of major mood disorders is the presence of significant changes in mood states, which can manifest as episodes of depression, mania, or mixed moods. Individuals experiencing these disorders often go through extreme shifts that can affect their emotional well-being, functioning, and overall quality of life.

For instance, a person with major depressive disorder might undergo periods of profound sadness and hopelessness, while someone with bipolar disorder may experience episodes of mania alternating with depressive states. These fluctuations can be drastic and have serious implications for the individual's daily activities and relationships, making it critical to recognize and appropriately address these changes in a clinical setting.

In contrast, the other options describe conditions that do not align with the nature of major mood disorders. The absence of mood variations, continuously elevated mood, and permanent mild mood disturbances are not representative of the severe and variable emotional states seen in these disorders.