What distinguishes a delusion from a hallucination?

The distinction between a delusion and a hallucination lies fundamentally in the nature of the experiences associated with each term. Delusions are false beliefs that are firmly held despite clear evidence to the contrary. They represent a misinterpretation of actual events and are typically resistant to reason or confrontation with factual information.

On the other hand, hallucinations pertain to sensory experiences that occur in the absence of an external stimulus; they are perceptions that seem real to the person experiencing them but do not actually exist in reality.

Given this context, the correct answer highlights that a delusion involves a misperception of reality. It focuses on the belief aspect rather than the sensory experience that characterizes hallucinations. This distinction is key in understanding diagnoses and treatment approaches in mental health, particularly for disorders such as schizophrenia or severe mood disorders where these phenomena can commonly occur.