In work recently published in the Journal of Psychopharmacologyscientists have breathed new life into a decades-old tool for understanding the psychedelic experience, expanding our understanding of these profound states of mind. By reviving and updating the Psychedelic Experience Scale, researchers can better explore the subjective effects of psychedelic substances, paving the way for new insights into consciousness and opening the door to innovative approaches to treating psychological diseases.
Psychedelic substances, such as LSD and psilocybin (found in magic mushrooms), have fascinated scientists and the public alike for decades. These substances were initially investigated in the 1950s and 1960s for their potential in psychiatric treatment and understanding of the human mind, but prompted the development of instruments to measure their effects on consciousness. However, legal and social setbacks at the end of the 20th century put pressure on this research.
Recently, there has been a renaissance in the scientific community’s interest in psychedelics, driven by promising results in the treatment of conditions such as depression, anxiety and post-traumatic stress disorder. This modern resurgence has necessitated better tools to quantify and understand the complex and multifaceted experiences these substances evoke.
“Studying the psychology of the psychedelic experience is a worthwhile endeavor. As studies have shown, such an experience is often very meaningful and is also often associated with lasting positive effects on attitude, mood and behavior in healthy individuals and – in combination with psychotherapy – with sustained symptom reduction in individuals suffering from depression, anxiety. and addiction,” explains study author Kurt Stocker, research associate in psychopharmacology at the University Hospital Basel and project leader for consciousness studies at ETH Zurich.
“Seeing such potential benefits from the psychedelic experience, it becomes clear that it would be helpful if we could psychometrically capture the important aspects of this experience as comprehensively and concisely as possible. The better we can capture the psychedelic experience, the better we can discover its actual beneficial aspects.”
Introducing the Psychedelic Experience Scale (PES), originally developed by Walter Pahnke and William Richards in the 1960s and 1970s. This tool was intended to comprehensively measure the psychedelic experience, covering aspects from mystical revelations to visual phenomena and emotional challenges.
Modern researchers have used the Mystical Experience Questionnaire (MEQ), derived from the PES, to assess the subjective effects of psychedelic substances. But while mystical experiences are an important and well-documented aspect, they do not encompass the entire psychedelic experience. By examining the psychometric properties of the PES, the researchers sought to uncover additional dimensions of the psychedelic experience that could be measured and studied systematically.
“The Psychedelic Experience Scale (PES) – with the analytical approaches developed in our paper – is a useful psychometric tool for this,” Stocker told PsyPost. “The experience spectrum encompasses mystical, visual and challenging/disturbing psychedelic experiences with a conceptual breadth and depth that remains unparalleled when it comes to capturing such an experience as comprehensively and concisely as possible within a single questionnaire.”
Using data from 140 healthy participants, who contributed a total of 239 PES measures from six different studies of classic psychedelics, the researchers successfully identified and validated four new subscales within the PES: Paradoxicality, Connectedness, Visual Experience, and Disturbing Experience .
The paradoxicality The subscale emerged from the analysis as a reflection of the psychedelic-induced realization that seemingly contradictory principles can both be true. This dimension captures experiences where conventional logic fails, and the individual confronts the limits of rational thought and delves into a realm where contradictions coexist. Items within this subscale relate to experiences of identity loss, dissolving temporal boundaries, and merging the self with the environment.
Connectedness, another newly identified dimension, includes feelings of universal love, intuitive insights into the nature of beings and objects, and an enhanced appreciation of beauty and interpersonal relationships. The experiences measured on this subscale resonate with the idea that psychedelics can break down the barriers that separate individuals from each other and from the natural world, promoting a sense of harmony and interconnectedness.
The visual experience subscale highlights another crucial aspect of the psychedelic journey: the occurrence of vivid, often profound visual phenomena. This dimension includes both the perception of intricate geometric patterns and the transformation of ordinary objects into works of extraordinary beauty.
Finally the painful experience subscale addresses the challenging aspects of psychedelic experiences, including feelings of fear, despair, isolation, and physical discomfort. This dimension is a crucial addition to the understanding of psychedelics, recognizing that these experiences are not universally positive or enlightening. Instead, they can also bring profound emotional turmoil and existential confrontation.
“With the PES, we have revived an old, expertly crafted questionnaire from the 1960s with modern, state-of-the-art analyzes that allow us to better capture essential aspects of the psychedelic experience than previously possible was within a single questionnaire. Stocker explained. “It is thus likely to be a useful tool in ongoing research efforts to identify the full range of possible beneficial aspects of the psychedelic experience.”
Interestingly, the MEQ includes the transcendence of time and space as one of the four core components of mystical experiences induced by psychedelics. The new findings reaffirmed that transcendence of time and space is a critical dimension of the mystical experience. But the researchers also found evidence that such transcendental experiences are not always part of what is traditionally considered a mystical experience.
“Feelings of transcendence of time and space (for example, feelings that you are experiencing eternity or infinity and that you are in a realm without boundaries of space) are usually considered an inherent part of the mystical experience,” Stocker told PsyPost. “Although we were also able to confirm the association between time/space transcendence and mystical experience with correlation analysis in the current paper, our additional exploratory hierarchical item clustering analysis still pointed to a more general, also somewhat mystical independent concept of transcendence that may arise. during the psychedelic experience.”
“The results of our cluster analysis suggest that this larger overarching concept of transcendence includes the transcendence of time and space, but also goes further to include transcending notions of self, body, and perhaps mind. This part of the cluster analysis did not surprise me, as such or similar statements (e.g. that timelessness and the feeling of bodylessness go hand in hand) have been made by many mystics throughout history, for example by the late medieval theologian, philosopher, and mystic Meister Eckhart .”
“But what did surprise me is that the cluster analysis suggests that such an experience of transcendence may not be inherently part of the mystical experience, but rather could be an experience in itself,” Stocker said. “If this proves to be true in future studies, it could be ‘big news’ for scholars of the mystical experience (e.g., psychologists, philosophers, religious studies scholars, psychedelic science scholars). ”
The refinement of the PES is a potentially important advance in psychedelic research, offering deeper insights into the nuanced experiences induced by these substances. However, like any scientific instrument, the PES has its limitations.
“Although the possibility of both comprehensive and concise coverage of the psychedelic experience with a single questionnaire seems conceivable, such a psychometric instrument is not currently available,” Stocker said. “The PES is a big step in that direction (the best option available to date), but the PES still has important gaps, especially when it comes to the autobiographical dimension of the psychedelic experience.”
“For example, the PES only covers parts of possible autobiographically relevant experiences that may occur during the psychedelic experience; it refers only to emotional breakthroughs and to what we sometimes call ‘personal problem solving’. The latter means, for example, that you view personal problems from one or more new perspectives, or that you have the feeling that personal problems have been dealt with in a constructive way during the psychedelic experience.”
“One of the next goals of the psychological work in our psychopharmacological research at the University Hospital Basel is a comprehensive measurement of the psychology of the psychedelic experience for both research and therapy, which will hopefully also result in a corresponding questionnaire,” Stocker explains . “In the meantime, however, the PES fulfills the fundamental goal of providing a comprehensive and concise representation of the psychedelic experience quite well.”
The study, “The revival of the psychedelic experience scale: Revealing its extended-mystical, visual, and distressing experiential spectrum with LSD and psilocybin studies,” was written by Kurt Stocker, Matthias Hartmann, Laura Ley, Anna M. Becker, Friederike Holze and Matthias E. Liechti.