Visual hallucinations during prolonged blindfolding in sighted subjects.
The authors report the occurrence of visual hallucinations of varying complexity in 13 normal subjects after sudden, complete, and prolonged visual deprivation. The subjects were all healthy individuals with no history of cognitive dysfunction, psychosis, or ocular pathology. They wore a specially designed blindfold for a period of five consecutive days (96 hours) and were asked to record their daily experiences using a hand-held microcassette recorder. Ten (77%) of the subjects reported visual hallucinations, which were both simple (bright spots of light) and complex (faces, landscapes, ornate objects). The onset of hallucinations was generally after the first day of blindfolding. Subjects were insightful as to their unreal nature. These results indicate that rapid and complete visual deprivation is sufficient to induce visual hallucinations in normal subjects.
Merabet
Lotfi B
LB
Laboratory for Magnetic Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115, USA.
Maguire
Denise
D
Warde
Aisling
A
Alterescu
Karin
K
Stickgold
Robert
R
Pascual-Leone
Alvaro
A
D000328:Adult; D001458:Bandages; D005260:Female; D006212:Hallucinations / Q000209:etiology*; D006801:Humans; D008297:Male; D010812:Physical Stimulation; D012016:Reference Values; D012683:Sensory Deprivation; D013997:Time Factors; D014110:Touch; D014785:Vision, Ocular