What is a hallmark symptom of depression?

A hallmark symptom of depression is the presence of persistent feelings of sadness or hopelessness. This symptom encapsulates the emotional experience of many individuals who are suffering from depression. These feelings are often overwhelming and can lead to a pervasive sense of despair that affects various aspects of an individual's life, including their ability to function in daily tasks, maintain relationships, and enjoy activities they once found pleasurable.

While other symptoms such as severe irritability can occur in depression, they do not define the disorder the way persistent feelings of sadness or hopelessness do. Excessive energy or enthusiasm, as well as frequent laughter, are typically contrary to the mood and emotional state associated with depression. Therefore, the consistent presence of sadness or hopelessness is a key indicator of the condition, helping to distinguish it from other mood states or disorders.