The Picture Sign in Dementia

Abstract

To the Editor:—Drs. Neitch and Zarraga describe a “misidentification delusion”1 which they claim has not previously been described. Not only has this phenomenon, the “delusional belief that pictures are real,” previously been described, but it has also been given a name, “the picture sign.”2 Berrios and Brook described seven patients “who treated TV images and newspaper photographs (eg a nude calendar girl) as if they were real and existed in the three-dimensional space.” These seven cases were part of 150 successive referrals to a psychogeriatrician in the city of Cambridge. They found no significant association between this sign and sex, age, underlying pathology, impending death, or score on the Blessed Information-Memory-Concentration test. No specific diagnoses were given for these seven patients, although over half the sample had a dementia. It has also been observed that 8% of a group of 110 research subjects with SDAT were unable to recognize that people on television were not physically present.3 One such subject refused to dress in a room with a television, and another feared they were being shot at by characters on the television. While these latter cases were not reacting to printed pictures per se, they are clearly included in the broader perceptual disorder described by Berrios. The phenomenology of dementia is complex, and identification of unique perceptual disorders is important as it may allow a better understanding of the underlying pathophysiology of these symptoms in a wide range of disorders. Drs. Neitch and Zarraga are to be applauded for bringing this interesting symptom to broader attention.