More than a quarter of people who regularly meditate have had a “particularly unpleasant” psychological experience, including feelings of fear and distorted emotions, according to a new study.

Researchers at the University of College London also found those who had attended a meditation retreat, those who only practiced deconstructive types of meditation, such as Vipassana (insight) and Koan practice (used in Zen Buddhism), and those with higher levels of repetitive negative thinking, were more likely to report a “particularly unpleasant” meditation-related experience.

However, the study, which was based on an international online survey of 1,232 people who had at least two months of meditation experience, found women and those with a religious belief were less likely to have had a “particularly unpleasant” experience.

“These findings point to the importance of widening the public and scientific understanding of meditation beyond that of a health-promoting technique,” said Dr. Marco Schlosser, a researcher in the UCL Division of Psychiatry and lead author of the study. “Very little is known about why, when, and how such meditation-related difficulties can occur. More research is now needed to understand the nature of these experiences.”

“When are unpleasant experiences important elements of meditative development, and when are they merely negative effects to be avoided?” he continued.

The study, conducted with researchers at Witten/Herdecke University in Germany and the University of Ljubljana in Slovenia, was triggered by a limited but growing number of research reports and case studies that indicate psychologically unpleasant experiences can occur when someone meditates. Some traditional Buddhist texts also reference vivid accounts of similar experiences, the researchers said.

However, very little is known about the prevalence of these experiences, they noted.

In the online survey, participants answered the following question: “Have you ever had any particularly unpleasant experiences (e.g. anxiety, fear, distorted emotions or thoughts, altered sense of self or the world), which you think may have been caused by your meditation practice?”

Participants also reported how long they would meditate and the frequency of practice, whether they had attended a meditation retreat at any point in their lives, and what form of meditation they practiced. They also completed measures of repetitive negative thinking and self-compassion.

The findings showed that:

  • Of the 1,232 participants, 25.6 percent indicated that they had previously encountered particularly unpleasant meditation-related experiences.
  • More male participants, 28.5 percent, experienced a particularly unpleasant experience, compared to 23 percent of female participants.
  • 30.6 percent of those who did not have a religious belief had a particularly unpleasant experience, compared to 22 percent of those who had a religious belief.
  • More people, 29.2 percent, who practiced only deconstructive types of meditation reported a particularly unpleasant experience, compared to 20.3 percent who only engaged in other meditation types.
  • And 29 percent of those who had been on a meditation retreat (at any point in life) had a particularly unpleasant experience, compared with 19.6 percent, who had never been on a retreat.

“Most research on meditation has focused on its benefits, however, the range of meditative experiences studied by scientists needs to be expanded,” Schlosser said. “It is important at this point not to draw premature conclusions about the potential negative effects of meditation.”

“Longitudinal studies will help to learn when, for whom, and under what circumstances these unpleasant experiences arise, and whether they can have long-term effects,” he continued. “This future research could inform clinical guidelines, mindfulness manuals, and meditation teacher training.”

The study was published in PLOS ONE.

Source: University College London