Chapter 2: The Prisoner's Cinema: Sensory Deprivation Summary and Analysis

In Chapter 2, Sacks discusses the hallucinations experienced by prisoners in the absence of perceptual change. Prisoners or any individual who is isolated in darkness can experience "the prisoner's cinema," or brilliantly colored and varied hallucinations. Even those with adequate light can experience the same, as perceptual monotony can have the same effect as the absence of light. In one of the first studies on sensory deprivation, college students were placed into soundproof and lightproof booths, and given gloves to reduce tactile stimulation. The result was eventual hallucinations, turning from simple to complex, with vivid detail. Later experiments involved water tanks, or sensory deprivation tanks, designed to remove all sense of body position or senses, and these experiments were often combined with hallucinogenic drugs. Further testing, using blindfolded subjects who could move...