This functional Magnetic Resonance Imaging study investigated high and low suggestible people responding to two visual hallucination suggestions with and without a hypnotic induction. Participants in the study were asked to see color while looking at a grey image, and to see shades of grey while looking at a color image. High suggestible participants reported successful alterations in color perception in both tasks, both in and out of hypnosis, and showed a small benefit if hypnosis was induced. Low suggestible people (...) could not perform the tasks successfully with or without the hypnotic induction. The fMRI results supported the self report data, and changes in brain activity were found in a number of visual areas. The results indicate that a hypnotic induction, although having the potential to enhance the ability of high suggestible people, is not necessary for the effective alteration of color perception by suggestion. (shrink)

We administered suggestions to see a gray-scale pattern as colored and a colored pattern in shades of gray to 30 high suggestible and eight low suggestible students. The suggestions were administered twice, once following the induction of hypnosis and once without an induction. Besides rating the degree of color they saw in the stimuli differently, participants also rated their states of consciousness as normal, relaxed, hypnotized, or deeply hypnotized. Reports of being hypnotized were limited to highly suggestible participants and only (...) after the hypnotic induction had been administered. Reports of altered color perception were also limited to high suggestibles, but were roughly comparable regardless of whether hypnosis had been induced. These data indicate that suggestible individuals do not slip into a hypnotic state when given imaginative suggestions without the induction of hypnosis, but nevertheless report experiencing difficult suggestions for profound perceptual alterations that are pheonomenologically similar to what they report in hypnosis. (shrink)

Ouija board sessions are illustrious examples of how subjective feelings of control – the Sense of Agency - can be manipulated in real life settings. We present findings from a field experiment at a paranormal conference, where Ouija enthusiasts were equipped with eye trackers while using the Ouija board. Our results show that participants have a significantly lower probability at visually predicting letters in a Ouija board session compared to a condition in which they are instructed to deliberately spell out (...) words with the Ouija board planchette. Our results also show that Ouija board believers report lower SoA compared to sceptic participants. These results support previous research which claim that low sense of agency is caused by a combination of retrospective inference and an inhibition of predictive processes. Our results show that users in Ouija board sessions become increasingly better at predicting letters as responses unfold over time, and that meaningful responses from the Ouija board can only be accounted for when considering interactions that goes on at the participant pair level. These results suggest that meaningful responses from the Ouija board may be an emergent property of interacting and predicting minds that increasingly impose structure on initially random events in Ouija sessions. (shrink)