Capgras Syndrome, also known as Capgras Delusion, is the irrational belief that a familiar person or place has been replaced with an exact duplicate — an imposter (Ellis, 2001, Hirstein, and Ramachandran, 1997).

This is something that I see periodically in the population of Alzheimer’s Disease and Related Dementia (ADRD) patients I work with as director of care for a home care agency. Named for Joseph Capgras, the French psychiatrist who first described it, this delusion also sometimes is seen in people who have schizophrenia or bipolar disorder, or where there has been some type of brain injury or disease. Regardless of its source, it is likely less rare than is typically believed by psychiatrists and psychologists (Dohn and Crews, 1986), and therefore deserves more public and professional awareness.