Altered states of consciousness are more common than believed in mind-body practices

Resume: A new study finds that altered states of consciousness (ASCs), such as those experienced during meditation, are more common than previously thought. 45% of respondents reported experiencing ASCs at least once, often leading to positive outcomes.

However, a significant minority also reported negative or even life-threatening suffering, highlighting the need for better support and understanding of these experiences.

Key Facts:

  • 45% of respondents reported experiencing non-pharmacologically induced ASCs.
  • ASCs are associated with both positive and negative well-being outcomes.
  • Many who experience negative consequences do not seek help.

Source: Mass General

Yoga, mindfulness, meditation, breathwork and other practices are gaining popularity for their potential to improve health and well-being. The effects of these practices are usually positive and sometimes transformative, but they are known to sometimes be associated with challenging altered states of consciousness.

New research by a team that includes researchers at Massachusetts General Hospital, a founding member of the Mass General Brigham health care system, reveals that altered states of consciousness associated with meditation practice are much more common than expected.

This shows a person's face.
This is much more than expected from the 5% (US) to 15% (UK) of this population estimated to have practiced mindfulness. Credit: Neuroscience News

Although many people reported positive results, sometimes even considered transformative, for a substantial minority the experiences were negative. The results are published in the journal Mindfulness.

“As more and more people engage in mindfulness, meditation and other contemplative and mind-body practices, we thought that altered states and their effects might be common in the general population.

“We conducted a series of international studies to investigate this and indeed found that such experiences were widespread,” said senior author Matthew D. Sacchet, PhD, director of the Meditation Research Program at Massachusetts General Hospital and associate professor of psychiatry at Harvard Medical. School.

“Changed states were usually followed by positive and sometimes even transformative effects on well-being,” Sacchet adds. In some cases, negative effects on well-being were also reported, with a small subgroup of individuals reporting substantial suffering.”

For the study, a panel of experts in the fields of psychiatry, neuroscience, meditation and survey design developed a questionnaire about the experience of altered states of consciousness.

Of the 3,135 adults in the US and Britain who completed the online questionnaire, 45% reported experiencing non-pharmacologically induced altered states of consciousness at least once in their lives.

This is much more than expected from the 5% (US) to 15% (UK) of this population estimated to have practiced mindfulness.

The experiences include derealization (the feeling of being detached from your environment), unifying experiences (a sense of oneness or ‘oneness’), ecstatic sensations, vivid perceptions, changes in perceived size, body heat or electricity, out-of-body experiences, and perception of non-physical light.

Respondents reported a mix of positive and negative well-being after altered states, with 13% claiming moderate or greater suffering and 1.1% reporting life-threatening suffering. Of those who experienced suffering, 63% did not seek help.

“Rather than being extremely uncommon and rare, our research found that altered states of consciousness are a common variant of the normal human experience,” says Sacchet.

“However, we have found that those who experience negative outcomes associated with these altered states often do not seek help, and that physicians are ill-prepared to recognize or support these types of experiences.

“This has contributed to what could be considered a public health problem, as a certain proportion of people have difficulty integrating their experiences of altered states into their existing views of themselves and reality.”

Sacchet noted that additional studies are needed to identify individual characteristics associated with experiencing altered states of consciousness, and with possible suffering associated with them. He also emphasized the importance of applying this research to patient care.

“We should not dismiss meditation and other practices as inherently dangerous, but we need to better understand and support meditators to fully realize the potential of these practices,” he said.

“As with psychotherapy, pharmacology and other therapeutic tools, it is important that we learn how to best implement and support people as they engage in these powerful practices.”

He added that “ancient meditation manuals from the wisdom traditions can be useful for classifying and understanding altered states of consciousness. They can provide guidance on how to better manage altered states when they can be difficult. We clearly need more research to further study and understand this possibility.”

“A clinical curriculum on altered states of consciousness should be developed to better support clinicians caring for patients experiencing suffering associated with these types of experiences,” Sacchet added.

“Also, those teaching meditation practices should ensure that participants are aware of potential risks,” he said.

“Together, these types of safeguards will ensure that these promising and powerful practices are taught and experienced safely.”

About this consciousness research news

Author: Noah Brown
Source: Mass General
Contact: Noah Brown – Mass General
Image: The image is credited to Neuroscience News

Original research: Open access.
“Altered states of consciousness are common and clinically undersupported: a population-based study” by Matthew D. Sacchet et al. Mindfulness


Altered states of consciousness are common and clinically insufficiently supported: a population study


Adopting potentially mind-altering practices can lead to an increase in emergent phenomena (EP): sudden unusual mental or somatic experiences that are often interpreted as spiritual, mystical, energetic, or magical in nature. It is unclear how often these altered states of consciousness occur and what the clinical implications may be.

Anecdotal accounts and previous literature suggest that EP is common, underreported, and followed by positive or negative changes in well-being. We sought to supplement previous evidence on the prevalence and effects of EP in the general population with large-scale quantitative measurements.


We measured the prevalence of EP, but not of mind-altering substances, by completing online surveys by representative samples from three international communities (N=3135). The communities studied were British Qualtrics online panelists, US-based MTurk employees, and the readers of a popular rationalist blog. The samples were broadly representative of the underlying populations.


Forty-five percent of participants reported experiencing non-pharmacologically induced EP at least once in their lives, including derealization (17%), unifying experiences (15%), ecstatic sensations (15%), vivid perceptions (11%), changes in perceived size (10%), body heat or electricity (9%), out-of-body experiences (8%), and perception of non-physical light (5%). Respondents reported a mix of positive and negative well-being outcomes after EP, with 13% claiming moderate or greater suffering and 1.1% claiming life-threatening suffering. Of those who experienced suffering, 63% did not seek help.


EP is widespread among the populations studied with potential for both positive and negative outcomes, the latter of which do not appear to be adequately addressed by recourse to clinical practice.