Loss of insight is a prominent clinical manifestation of behavioral variant frontotemporal dementia , but its characteristics are poorly understood. Twelve bvFTD patients were compared with 12 Alzheimer’s disease patients on a structured insight interview of cognitive insight and emotional insight . Compared to the AD patients, the bvFTD patients were less aware and less concerned about their disorder, and they had less appreciation of its effects on themselves and on others. After corrective feedback , the bvFTD patients were just (...) as aware of their disorder as the AD patients but remained unconcerned and unappreciative of its effects. These findings suggest that lack of insight in bvFTD is not due to “anosognosia,” or impaired cognitive and executive awareness of disease, but to “frontal anosodiaphoria,” or lack of emotional concern over having bvFTD and its impact on themselves and others. (shrink)