A New Environmental Dependency Syndrome Occurring With Frontotemporal Lobe Degeneration: Hypervisual Illusory Spread Syndrome.

A 59-year-old man presented with non-fluent aphasia and behavioral variant frontotemporal lobe degeneration (FTD), volunteered unusual visual symptoms that were best described as illusory visual spread (the image spreading over a larger area). This type of visual hyperfunction, related to the palinopsia syndromes, has not been reported in association with FTD. The syndrome may be best understood in terms of a visual variant of the environmental dependency syndrome, akin to the verbal variant of forced hyperphasia syndrome.