A patient describes an unsettling sense that something significant is happening. Before revealing the answer, decide what distinguishes delusional mood from delusional perception.

Ask whether the experience has any specific, crystallised content, or whether it remains a vague, unformed sense that something significant is happening. Delusional mood lacks any specific, crystallised content of its own — it is precisely the unformed state that often precedes a delusional perception or a sudden delusional idea, carrying only a diffuse sense of personal significance. Delusional perception is the more advanced, specific stage: a normal perception of a real object or event to which a definite, crystallised delusional meaning has become attached. Delusional mood often resolves into a delusional perception, sometimes with a sense of relief once the vague, unsettling feeling finally gains concrete meaning, making the two closely related stages of the same underlying process.