Milton Erickson was one of the leading researchers of hypnosis in the 20th century. He was a psychiatrist who specialized in medical hypnosis. He founded the American Society for Clinical Hypnosis. He also influenced neuro-linguistic programming (NLP) and conducted in-depth research on the power of the unconscious mind including several studies of color.
Erickson and Erickson (1938) conducted a study involving 4 participants. They received hypnotic suggestions that a white piece of paper was actually red, blue, green, or yellow. They were given specific hypnotic suggestions to see the complementary color of a previous sheet when shown a white piece of paper. The results showed that all 4 participants hallucinated the complementary color of the preceding sheet of paper. This was the result of the hypnosis and hypnotic suggestions.
Erickson (1939) conducted another study having to do with color and hypnotic suggestion. This study involved color-blindness. The study involved 6 participants with normal vision. However, the hypnotic suggestions were designed to induce color-blindness. An Ishihara test was conducted to determine the extent of color blindness. One participant associated the number 3 with the color red and after receiving the hypnotic suggestions, was not able to comprehend the number 3. This study led Erickson to determine that color blindness originates in the cortical area of the brain and hypnosis can influence it.
Another study included 8 highly hypnotizable participants. The goal of the study was to provide insight into hypnosis and to see if hypnosis affects color perception. The participants were asked to see a specific color pattern while receiving a positron emission tomography (PET) scan. Researchers looked at the fusiform and lingual areas of the brain and compared the images of when participants saw color patterns and when they saw gray patterns.
Results of this study (during hypnosis) showed that the left and right hemispheres of the brain showed activity when the participant was asked to see color. However, when the participants were asked to see gray, there was reduced activity in the brain. The study also showed that there were changes in blood flow in the left hemisphere of the brain whether the participant had received hypnosis or not. The findings of this study show that hypnosis is a state of consciousness with distinct neural correlates.
By Steve G Jones