Some individuals have the ability to hallucinate colors at will, according to scientists at the University of Hull. The research — centered on a group of people already known to be ‘highly suggestible’ during hypnosis — was conducted by the university’s department of psychology.
Less suggestible people — people less likely to respond to hypnosis — were also included in the study as a control group.
During the study, participants were told to look at a series of monochrome patterns and try to see the color in them. They completed this task under hypnosis and without hypnosis; both times, suggestible subjects reported that they were able to see colors, while individuals in the non-suggestible group were not able to hallucinate color.
Through an MRI scanner, participants’ reactions to the patterns were also captured; this allowed the researchers to keep track of the differences in brain activity between the suggestible and non-suggestible subjects. In the suggestible subjects only, there were significant changes in brain activity in areas of the brain responsible for visual perception.
“These are very talented people,” said Professor Giuliana Mazzoni, lead researcher on the project. “They can change their perception and experience of the world in ways that the rest of us cannot.”
Changing one’s experience at will can be a very useful ability. Studies have already shown that hypnotic suggestions are effective for blocking pain and increasing the effectiveness of psychotherapy.
It was assumed that hypnosis was a requirement for these effects to occur; however, the new study suggests that this is not the case. Even though hypnosis does seem to intensify the participants’ ability to see color, the ‘suggestible’ subjects were also capable of seeing colors and changing their brain activity without the help of hypnosis.
The MRI scans showed clearly that although it was not necessary for the participants to be under hypnosis in order to perceive colors in the tests, it was evident that hypnosis increased the ability of the subjects to experience these effects.
“Many people are afraid of hypnosis, although it appears to be very effective in helping with certain medical interventions, particularly pain control. The work we have been doing shows that certain people may benefit from suggestion without the need for hypnosis,” said Dr. William McGeown, who was also a contributor in the study.
The study is published in the journal Consciousness and Cognition.
Source: University of Hull