Sensory Deprivation

1937

Donald O. Hebb (1904–1985)

Canadian psychologist Donald Hebb began investigating the effects of light and dark deprivation on infant mammals in the late 1930s. In 1937, he became a research fellow at the Montreal Neurological Institute. By the late 1940s other scientists had begun researching sensory deprivation beyond the withholding of light and dark. Much of the initial research was devoted to understanding the role of early life experiences on brain development and behavior in a variety of organisms.

Subsequently, in the early years of the Cold War between the United States and the Soviet Union, American military and political leaders became concerned about the possible brainwashing of captured American soldiers. In order to understand the phenomenon, military and intelligence services provided funding for psychological research on humans, including studies of sensory deprivation. They hoped that this research would explicate a process, like brainwashing, whereby a normal adult could be induced to believe and act contrary to his or her normal state of conscious functioning.

At the request of both the United States and Canadian governments, Hebb and his colleagues, along with a number of other scientists, pursued their inquiries into the role of sensory deprivation and its psychological consequences for adult humans. Using several variants of sensory deprivation or isolation, the research showed the fundamental importance of sensory and social stimulation for normal psychological functioning; that is, participants in these studies who were isolated or deprived in various ways suffered a surprising range of impairments during and after the period of deprivation. These included psychotic thinking, delusional states, inability to think clearly or to concentrate, deficits in performance on many intellectual and motor tasks, hallucinations, paranoid ideation, somatic complaints, time-and-space disorientation, and high levels of anxiety. Many participants also experienced impairments in social functioning that endured after the period of deprivation. The research on sensory deprivation revealed a marked human need for richness of both sensory and social stimulation as well as a vulnerability to psychological manipulation when such stimulation is absent.

SEE ALSO Choosing the Right Stuff (1958)

A poster for the National Institutes of Health lecture, “Visual Deprivation and Its Effects on the Monkey Striate Cortex,” 1975.