Walsh & Hoyt: Visual Perseveration

The persistence, recurrence, or duplication of a visual image is a rare complaint in patients with cerebral lesions. Several varieties exist, including palinopsia, polyopia, and illusory visual spread. Palinopsia (or paliopsia) is the perseveration of a visual image in time. Whereas the content of visual hallucinations is often imagery created de novo, or sometimes from the distant past (experiential hallucinations), the palinopsic illusion contains elements of a more recently viewed scene, or even one that is still being viewed. Nevertheless, the difference is not always distinct, and patients can have both perseverative and hallucinatory phenomena concurrently. Cerebral diplopia or polyopia is the perseveration of a visual image in space, when two or more copies of a seen object are perceived simultaneously.