When Your Loved One With Lewy Body Dementia Thinks You're an Imposter

Lewy body dementia can lead to Capgras syndrome, where a person believes loved ones are identical-looking imposters. The condition affects about 20% of people with Lewy body dementia and involves misidentification tied to protein clumps known as Lewy bodies. These clumps affect two nerve pathways: those that carry visual information to the brain and those that help interpret it. As a result, an individual may recognize a face but not identify who it belongs to, concluding the person is an imposter. Capgras episodes can come and go, with episode duration varying. The article also outlines Lewy body dementia’s progression—memory loss, agitation, REM sleep behavior disorder, hallucinations, delusions, Parkinson-like symptoms—and notes that cholinesterase inhibitors such as Aricept, Exelon, and galantamine may reduce delusions and visual hallucinations.