Originally published in Comfort Zone Newsletter: November 2010
This study was done by Annette Kjellgren, Andreas Lindahl, and Torsten Norlander, three researchers in the psychology department at Karlstad University in Sweden. In the process of exploring the effect of sensory isolation flotation tanks, they looked at whether being highly sensitive made any difference in people’s experiences. They had 48 subjects; each spent 45 minutes in the tank. Before and after their flotation period they filled out various tests, including the HSP Scale.
For the analysis of the data, the 48 were divided into those who scored high and those who scored low on sensitivity and then the two groups were compared. The high sensitivity group experienced significantly more mystical experiences and higher degrees of altered states of consciousness than the group of subjects low in sensitivity.
Other analysis found that the HSPs showed more stress and arousal when they arrived, but did not differ from the non-HSPs in depression or optimism. Both groups experienced the same amount of stress reduction and comfort, but the HSPs were more likely to have these additional mystical and altered-state experiences.
This research was reported in Individual Differences Research, Vol. 7 (4), December 2009, pp. 212-221.