Abstract
Background
Psychedelic use and its impact on well-being is garnering a lot of research attention, however, little has been done to understand the potential associations between multiple characteristics of the psychedelic experience and psychological flexibility (PF), which encompasses a conscious awareness of thoughts and behavior, allowing individuals to adapt to new experiences and perceive multiple explanations or solutions for life events.
Aims
The current study examines the psychedelic correlates of PF. It was hypothesized that intention, comfort and safety during the experience, decentering, mystical experiences, ego-dissolution, and insight would be significantly associated with greater reports of PF.
Methods
Data used for the regression analysis were from 114 participants who had used one of the classic psychedelics (LSD, Psilocybin, Mescaline, DMT, Ayahuasca, 5MeO-DMT) and were recruited from postings on Twitter (now X) and within psychedelic-based groups on Facebook and Reddit to fill out an online survey. Standard assessments used include the Experiences Questionnaire, Mystical Experience Questionnaire, Ego-Dissolution Inventory, Cognitive Flexibility Inventory, Psychological Insight Questionnaire, and Religious Salience Scale.
Results
After controlling for sociodemographics (age, income, religious salience, number of psychedelic experiences), self-perceived meaningful intention and decentering remained significantly associated with greater psychological flexibility.
Conclusions
These results expand upon existing literature on psychedelic use and its impact on well-being by exploring specific characteristics of the psychedelic experience. Understanding the importance of intention and decentering can provide a pathway by which psychedelic users, guides, and researchers can further understand the psychedelic experience and its effects.
Introduction
The resurgence of interest in psychedelics is being hailed a renaissance (George, Hanson, Wilkinson, & Garcia-Romeu, 2022; Sessa, 2018). The investigation into these substances encompasses biological mechanisms, psychological correlates, and therapeutic interventions. To date, most psychedelic research has focused on outcomes of psychedelic experiences, for example, the impact of use on disorders such as depression, anxiety, eating disorders, and addiction (Hosanagar, Cusimano, & Radhakrishnan, 2021; Muttoni, Ardissino, & John, 2019). A few studies have investigated the mediators of these outcomes (e.g., mystical experiences; Griffiths et al., 2016, 2018; Garcia-Romeu, Himelstein, & Kaminker, 2015), but more research is clearly needed. Another variable that has been proposed and tested as a mechanism for explaining the therapeutic benefits of psychedelic use is psychological flexibility (PF; e.g., Agin-Liebes et al., 2022). While there is a growing body of research on this construct, little is known regarding which characteristics of the psychedelic experience may be influencing changes in PF. Therefore, the aim of the current study was to investigate the associations between classic psychedelics, psychological flexibility (PF), and psychological processes elicited during the psychedelic session such as self-perceived meaningful intention, feelings of comfort/safety during the experience, decentering, mystical experiences, ego-dissolution, and insight.
Psychological flexibility
PF includes the processes and behaviors linked with being “open, aware, and active” (Vlaeyen, 2014, p. 235) and is positively associated with greater well-being (Arslan & Allen, 2022; Davis, Barrett, & Griffiths, 2020). PF has been defined in a variety of ways: the focus in the neuro-psychological literature has been predominantly cognitive, and often referred to as cognitive flexibility (CF; Whiting, Deane, Simpson, McLeod, & Ciarrochi, 2017), while the focus in clinical areas has been more multi-dimensional, as in the Psychological Flexibility Model (PFM; Watts & Luoma, 2020, see below).
According to Calabrese II (1994) and Kashdan and Rottenberg (2010), PF consists of executive control or self-regulation, default mental states, and personality traits. Executive control involves a conscious awareness of thoughts and behavior in comparison to default tasks or habits (Miller & Wallis, 2009). Individuals high in PF adapt quickly to situations, perceive multiple explanations or solutions for life events, and alter behavior to attain goals (Goldberg, 2001; Kashdan & Rottenberg, 2010). Default mental states are habits, stereotypes, or shortcuts for making quick decisions (Kashdan & Rottenberg, 2010). Those high in PF tend to be more mindful of stereotypes they hold, and have an awareness of their habits, which can facilitate positive behavior change, reduce stigma, and enhance empathy (Kashdan & Rottenberg, 2010; Masuda, Hill, Morgan, & Cohen, 2012; Valdivia-Salas, Martin-Albo, Cruz, Villanueva-Blasco, & Jiménez, 2021). Personality traits of PF include low neuroticism and high openness (Kashdan & Rottenberg, 2010). Those low in neuroticism have better psychological, cognitive, and physical health outcomes, which could explain PF's association with well-being. Individuals high in PF are also more likely to be open to new experiences, thoughts, emotions, and sensations (Kashdan & Silvia, 2009).
PF has also been defined through the lens of psychedelic-assisted therapy. One type of psychedelic-assisted therapy is Acceptance and Commitment therapy (ACT; Guss, Krause, & Sloshower, 2020; Sloshower et al., 2020) which uses the PFM (Watts & Luoma, 2020). For those using ACT/PFM, six processes constitute PF: acceptance, cognitive defusion (i.e., processes of creating a space between detrimental thoughts and emotions; Hayes, Luoma, Bond, Masuda, & Lillis, 2006), being in the moment, self as context (i.e., awareness of experiences without being attached to them), values (i.e., determining what is important in one's life), and committed action (i.e., taking action towards one's values; Hayes et al., 2006). PF, as defined in this multidimensional approach, is associated with increases in well-being as well as decreases in distress (Wersebe, Lieb, Meyer, Hofer, & Gloster, 2018). Additionally, both CF and PFM approaches show other similar outcomes including how impairments in PF (i.e., cognitive or psychological inflexibility) are associated with psychopathology (McDonald, Flashman, & Saykin, 2002; Niemeier, Marwitz, Lesher, Walker, & Bushnik, 2007).
Research on psychedelics and PF
There is a growing body of research on the relationship between psychedelic use and PF. In one longitudinal study, Close, Hajien, Watts, Roseman, and Carhart-Harris (2020) found psychedelic experiences were associated with significant increases in PF up to four weeks later, especially for participants who scored low on PF at baseline. Increases in PF during the psychedelic experience are associated with a host of beneficial outcomes. For example, Mangini, Averill, and Davis (2021) explored ibogaine and 5-MeO-DMT as a treatment modality in veterans; they found increases in PF were associated with reductions in alcohol use and post-traumatic stress symptoms. This is in alignment with prior research showing increases in PF and quality of life with use of psychedelics such as ayahuasca and LSD (Carhart-Harris et al., 2016; Jiménez-Garrido et al., 2020). Indeed, more recent work has found that increases in positive mood associated with ceremonial use of ayahuasca were due to increases in PF (Agin-Liebes et al., 2022).
Although psychedelic use is associated with increases in PF, which in turn are associated with beneficial outcomes, less is known about which characteristics of the psychedelic experience are associated with PF and might be driving the increase in PF after psychedelic use. Some evidence points to variables such as set and setting, such as one's intention and feelings of comfort/safety before and during the session, in addition to characteristics of the experience itself, such as decentering, mystical-type experiences, ego-dissolution, and insight. Thus, the primary aim of this study was to examine these characteristics as potential predictors of PF in classic psychedelic experienced participants.
Set and setting
Set and setting are the internal and external contextual factors of psychedelic use (Gukasyan & Nayak, 2021). Set refers to one's mindset, which may include thoughts, feelings, emotions, a sense of preparedness, intentions, expectations, or other psychological factors brought into the experience. Setting refers to one's external environment of the experience (i.e., when/where the experience is occurring; Carhart-Harris et al., 2018). We focus specifically on intention and comfort/safety.
Intention
Setting an intention for a psychedelic experience involves the user forming meaningful goals or hopes prior to the experience; it often represents the purpose for seeking out the experience. Intentions can have important effects on outcomes; for example, in a sample of individuals with plans to use a classic psychedelic (Haijen et al., 2018), those who set clear intentions reported greater mystical experiences and fewer challenging experiences after actual use. In a more recent report of MDMA users, Elmer, Vannoy, Studerus, and Lyubomirsky (2024) found significant differences by types of intentions for the majority of positive social-emotional outcomes, but not for the majority of negative outcomes; specifically, self-insight intentions and a combination of insight plus “hedonistic” intentions (e.g., euphoria/energy) were related to greater perception of positive outcomes, such as increased empathy and improved relationships, compared to hedonistic intentions alone. Taken together, these findings suggest that intention setting may facilitate successful outcomes and minimize negative outcomes of a psychedelic session. Perhaps those who set clear, meaningful intentions have an easier time letting go and allowing the session to flow without resistance, thus allowing them to receive the benefits and mitigate the challenges that may arise. Indeed, in psychedelic therapy, clients are often encouraged to include letting go as part of their intention for the session (e.g., Wolff et al., 2020). Additionally, in other domains, it has been posited that goal setting and planning free up cognitive resources by “passing control over to automatic processes” (e.g., Masicampo & Baumeister, 2011, p. 668). This might allow for greater present-moment focus. In this way, setting intentions may enhance PF through fostering greater adaptability and acceptance. More research is needed to uncover associations between intentions and PF in psychedelic studies.
Comfort and safety
An important aspect of the psychedelic session is feeling comfortable and safe. Safety (both physical and psychological) is part and parcel to well-being in general (Slavich, 2020), and particularly important during clinical experiences (e.g., Crits-Christoph, Rieger, Gaines, & Connolly-Gibbons, 2019; Mollon, 2014). The degree of comfort/safety likely affects the ability to express one's authentic self during a psychedelic experience and can have a pronounced effect on outcomes. For example, in a longitudinal study of psilocybin use, comfortability in the environment was associated with greater well-being (Haijen et al., 2018). Similarly, in a recent study of ayahuasca use, comfort/safety was associated with less occurrence of challenging experiences and greater occurrence of mystical experiences (Pontual et al., 2022). These findings make sense given research showing safety (i.e., trust) is associated with exploration, mindfulness, self-regulation, and openness to negative affect (e.g., Heylen et al., 2019); indeed, feeling safe “provides the neural platform for … enabling … learning, creativity, appreciation of aesthetics, and even spirituality” (Porges, 2022, pg. 3). Given this, PF might be more likely to emerge as an outcome of the psychedelic experience if individuals feel safe; however, to the best of our knowledge, there are no studies testing the direct relationship between comfort/safety and PF.
Psychedelic experience characteristics
Characteristics of the psychedelic experience, such as decentering, mystical experiences, and ego-dissolution may also predict greater PF, but little prior research has examined this possibility.
Decentering
Decentering is the ability to detach from the self and recognize thoughts and emotions as temporary (Fresco et al., 2007). Decentering may serve a critical role in the process of self-reflection and may predict PF through cognitive reappraisal, which occurs when an individual changes the meaning of experiences by re-evaluating their emotions towards the event (Gross & John, 2003). Decentering may serve as a predictor for PF, allowing individuals to perceive multiple explanations and solutions for day-to-day life events and challenges without getting caught in patterned thinking.
Mystical experiences
Mystical-type experiences are commonly reported subjective effects of psychedelic substances and encompass the sense of internal and external unity or connection, noetic quality (i.e., the experience serves as objective truth), sacredness, bliss, peace, love, distortions in space/time, and the formation of hallucinations (Barrett, Johnson, & Griffiths, 2015; Griffiths, Richards, McCann, & Jesse, 2006). Notably, clinical trials find that mystical experiences are a critical component in the therapeutic success of psychedelics, leading to reductions in depression, anxiety, and improvements to well-being (e.g., Garcia-Romeu et al., 2015; Griffiths et al., 2016, 2018). Kaelen et al. (2018) and Davis et al. (2020) suggest that mystical experiences may be predictive of PF, which may be due to an acceptance and/or release of emotions (MacLean, Johnson, & Griffiths, 2011), however more research is needed in understanding mystical experiences and PF in the context of other characteristics of the psychedelic experience.
Ego-dissolution
Ego-dissolution is an experience of self-awareness (Letheby & Gerrans, 2017), where a user's ego-boundaries dissolve and there is a significant or complete loss of self, and/or a deep sense of universal connection (Nour, Evans, Nutt, & Carhart-Harris, 2016). Ego-dissolution may increase PF by facilitating individuals to understand that their concerns, self-interests, and tendencies to focus on the self are unimportant in the ‘grand scheme of things’. However, more research is needed to support these assumptions and the potential association between ego-dissolution and PF.
Insight
Gaining insight is often reported after having a psychedelic experience, including realizations about maladaptive ways of coping, clarity on the direction to move one's life, being more empathetic towards others, and understanding that thoughts and emotions are connected to prior life events (Davis, Xin, Sepeda, Garcia-Romeu, & Williams, 2021). Insight may facilitate greater awareness that alternative explanations exist for why difficult situations occur and thereby lead to various solutions for coping with such situations. Thus, it makes sense that insight would be associated with PF by modifying one's life values and behavior (Lerner & Lyvers, 2006; Watts & Luoma, 2020).
The current study
Psychedelic research to date has mainly focused on therapeutic outcomes rather than processes of change. PF has been explored as an explanatory construct for these benefits, however, little research has been conducted on what it is about the psychedelic experience that might be driving increases in PF. Therefore, the current study aims to further understand the psychedelic correlates of PF. Specifically, it was hypothesized that intention, comfort/safety during the experience, decentering, mystical experiences, ego-dissolution, and insight would be significantly associated with greater reports of PF. We do not posit specific hypotheses about the relative contribution of each of these characteristics when examined simultaneously and thus consider that to be exploratory.
Methods
Participants
The current study recruited participants from social media [e.g., Twitter (now known as “X”), Reddit, Facebook] who had previously used classic psychedelics or were interested in using classic psychedelics within the next year. Inclusion criteria were being 18 years of age or older and having a working proficiency of English. A total of 449 participants attempted the survey. For the purposes of the analysis reported here, only those who had previously used a psychedelic are included. After cleaning the data, 182 participants were removed, leaving a total of 267 eligible for analyses (see Fig. 1).
Participant flow diagram
Citation: Journal of Psychedelic Studies 9, 1; 10.1556/2054.2024.00350
Participants were on average 31 years old (SD = 11.4; ranging from 18 to 66) and 58.1% indicated having taken a classic psychedelic at least 10 times in their life. The majority identified as male (61.2%), White (74.1%), and heterosexual/straight (69.4%); 52.4% reported an education below an Associate's Degree and 47.6% reported an Associate's Degree or greater. Most participants reside in North America (79.4%) and earn a pre-tax income of $74,999 or lower (63.5%). See Table 1.
Demographic characteristics
| Sample characteristics | N | Valid %a | Total %b | M (SD) | |
| Age | 164 | 100% | 61.4% | 31 (11.4) | |
| Gender | |||||
| Male | 104 | 61.2% | 39% | ||
| Female | 57 | 33.5% | 21.3% | ||
| Non-Binary | 7 | 4.1% | 2.6% | ||
| A gender not specified | 2 | 1.2% | 0.7% | ||
| Sexual Orientation | |||||
| Heterosexual or Straight | 118 | 69.4% | 44.2% | ||
| Bisexual | 37 | 21.8% | 13.9% | ||
| An orientation not listed | 5 | 2.9% | 1.9% | ||
| Queer | 3 | 1.8% | 1.1% | ||
| Pansexual | 2 | 1.2% | 0.7% | ||
| Heteroflexible | 2 | 1.2% | 0.7% | ||
| Gay | 2 | 1.2% | 0.7% | ||
| Lesbian | 1 | 0.6% | 0.4% | ||
| Race | |||||
| White/Caucasian American/European American | 126 | 74.1% | 47.2% | ||
| Other | 25 | 14.7% | 9.4% | ||
| Latino/a/x, Hispanic | 9 | 5.3% | 3.4% | ||
| Asian, Southeast Asian or Pacific Islander | 5 | 2.9% | 1.9% | ||
| African American | 2 | 1.2% | 0.7% | ||
| Middle Eastern | 2 | 1.2% | 0.7% | ||
| Black/Caribbean, West Indian | 1 | 0.6% | 0.4% | ||
| Education Level | |||||
| Less than 12 years of education | 1 | 0.6% | 0.4% | ||
| Pre-university educational completion or equivalent (e.g., in the U.S., the term is High School/GED) | 23 | 13.7% | 8.6% | ||
| Some university classes or no degree | 47 | 28.0% | 17.6% | ||
| Technical or trade/vocational school | 17 | 10.1% | 6.4% | ||
| Associate's Degree | 14 | 8.3% | 5.2% | ||
| Bachelor's Degree | 40 | 23.8% | 15.0% | ||
| Master's Degree | 17 | 10.1% | 6.4% | ||
| PhD or other Professional Degree (PsyD, MD, JD, DVM, etc.) | 9 | 5.4% | 3.4% | ||
| Residence | |||||
| North America | 135 | 79.4% | 50.6% | ||
| Europe | 26 | 15.3% | 9.7% | ||
| Australia | 5 | 2.9% | 1.9% | ||
| Central America | 1 | 0.6% | 0.4% | ||
| South America | 1 | 0.6% | 0.4% | ||
| Asia | 1 | 0.6% | 0.4% | ||
| Pacific Islands | 1 | 0.6% | 0.4% | ||
| Income Before Taxes (Converted to USD) | |||||
| 24,999 or lower | 37 | 25% | 13.9% | ||
| 25,000 – 49,999 | 36 | 24.3% | 13.5% | ||
| 50,000 – 74,999 | 21 | 14.2% | 7.9% | ||
| 75,000 – 99,000 | 16 | 10.8% | 6.0% | ||
| 100,000 or greater | 31 | 20.9% | 11.6% | ||
| Unknown | 7 | 4.7% | 2.6% | ||
| Current Religious Affiliation | |||||
| Not currently affiliated | 102 | 60.7% | 38.2% | ||
| Other | 31 | 18.5% | 11.6% | ||
| Christian or Protestant (e.g., Baptist, Presbyterian, Lutheran, etc.) | 12 | 7.1% | 4.5% | ||
| Buddhist | 8 | 4.8% | 3.0% | ||
| Catholic | 6 | 3.6% | 2.2% | ||
| Jewish | 2 | 1.2% | 0.7% | ||
| Pantheist | 2 | 1.2% | 0.7% | ||
| Agnostic | 2 | 1.2% | 0.7% | ||
| Muslim | 1 | 0.6% | 0.4% | ||
| Hindu | 1 | 0.6% | 0.4% | ||
| Taoist | 1 | 0.6% | 0.4% | ||
| Previous Religious Affiliation | |||||
| Yes | 71 | 59.2% | 26.6% | ||
| No | 49 | 40.8% | 18.4% | ||
| Religious Identification | |||||
| Spiritual | 51 | 30% | 19.1% | ||
| Spiritual & Agnostic | 43 | 25.3% | 16.1% | ||
| Spiritual, Agnostic, & Atheistic | 19 | 11.2% | 7.1% | ||
| Atheistic | 15 | 8.8% | 5.6% | ||
| Agnostic | 14 | 8.2% | 5.2% | ||
| Agnostic & Atheistic | 13 | 7.6% | 4.9% | ||
| Spiritual & Atheistic | 9 | 5.3% | 3.4% | ||
| Neither Spiritual, Agnostic, & Atheistic | 6 | 3.5% | 2.2% | ||
Note. A. Valid % represents participants who responded to the item. B. Total % represents the 267 participants eligible for analyses. C. Cases with more than one racial identity or current religious affiliation were categorized into ‘other’.
Procedure
The Institutional Review Board approved this study (Protocol #: 2021-0011). Participants were recruited from social media postings on X (formerly Twitter) and within psychedelic-based groups on Facebook and Reddit. A Qualtrics link to the survey was provided and once participants consented, they were directed to the questions.
Measures
General use (“consumption”) questions
Psychedelic consumption information was gathered. We asked how many times a participant had taken a classic psychedelic before, the type used, exact dose, believed strength of dose, route of administration, whether they were under the influence of other psychoactive substance(s) (excluding caffeine and nicotine), time since the experience, and whether music was present.
Set and setting
Participants answered context-relevant questions to capture set and setting, including having an intention (yes/no), perceived meaningfulness of the intention, rated on a scale from 1 (not meaningful) – 10 (very meaningful), and comfort/safety level directly prior to and during the experience, rated from 1 (not comfortable/safe at all) to 10 (very comfortable/safe).
Characteristics of psychedelic experience
Participants responded to survey items thinking of either their sole psychedelic experience if they had only used once before, or their most meaningful psychedelic experience if they had used more than once.
Decentering
The 13-item decentering subscale of the Experiences Questionnaire (Fresco et al., 2007) assessed ability to detach from the self and recognize thoughts and emotions as temporary processes of the mind. Responses to items (e.g., “I can observe unpleasant feelings without being drawn into them”) were rated from 1 (never) to 5 (all the time) and summed to create a total; higher scores represent greater decentering. The measure was reliable in this sample (α = 0.88).
Mystical experiences
Three subscales from the Revised Mystical Experiences Questionnaire (Barrett et al., 2015) containing a total of 27 items were used to measure different types of mystical experiences: mystical experiences (“Experience of oneness or unity with objects and/or persons perceived in your surroundings”), positive mood (“Feelings of peace and tranquility”), and space/time (“Loss of your usual sense of time”). All items were rated from 0 (None; not at all) to 5 (Extremely; more than ever before in my life and stronger than four). Subscale scores were summed, with higher totals representing greater mystical experience. In the current sample, the reliability was high: 0.96 for mystical experiences, 0.89 for positive mood, and 0.88 for space/time. For all three subscales combined, α = 0.96.
Ego-dissolution
The 8-item ego-dissolution subscale of the Ego-Dissolution Inventory (EDI; Nour et al., 2016) assessed the loss of sense of self, the extent to which ego-boundaries were disrupted during the psychedelic session, and the sense of union with one's surroundings (e.g., “I felt at one with the universe,” “I felt far less absorbed by my own issues and concerns''). Items were scored from 0 (“No, not more than usually”) - 100 (“Yes, entirely or completely”) and summed such that higher scores represent greater levels of ego-dissolution. Reliability was good (α = 0.88).
Insight
The Psychological Insight Questionnaire (Davis et al., 2020) consists of 28 items used to measure the degree to which respondents experience acute insight. Items are scored from 0 (“No; not at all”) to 5 (“Extremely, more than ever before in my life”) and summed to create a total, with higher scores reflecting greater insight. Sample items included: “Realized how current feelings or perceptions are related to events from my past” and “Discovered how aspects of my life are affecting my well-being”. The measure was highly reliable in the current sample (α = 0.97).
Psychological flexibility
The Cognitive Flexibility Inventory (CFI; Dennis & Vander Wal, 2010) was selected to assess PF. It consists of 20 items used to measure three aspects of PF: the tendency to perceive difficult situations as controllable (e.g., “When encountering difficult situations, I become so stressed that I cannot think of a way to resolve the situation”), the ability to perceive multiple alternative explanations for life occurrences and human behavior (e.g., “I consider multiple options before making a decision”), and the ability to generate multiple alternative solutions to difficult situations (e.g., “I often look at a situation from different viewpoints”). Items were rated on a scale of 1 (Strongly disagree) to 7 (Strongly agree) with six items being reverse scored; items were summed such that higher scores reflect greater PF. The current study showed an α of 0.91.
Socio-demographics
Participants answered questions regarding age, gender identity, sexual orientation, education level, income, residence, race/ethnicity, religious affiliation, and religious identification. In addition, the five-item Religious Salience Scale (Blaine & Crocker, 1995) was used to measure the prominence or importance of religion in everyday thoughts and feelings. Items were measured on a scale from 1 (“Strongly Disagree”) to 7 (“Strongly Agree”). Sample items include: “My religious or spiritual beliefs are what lie behind my whole approach to life” and “Being a religious or spiritual person is important to me.” All items were summed, with higher totals reflecting greater perceived importance of religion/spirituality. Reliability in the current study was high (α = 0.94).
Planned data analysis
All analyses were performed with IBM SPSS Statistics – Version 27, using pairwise deletions. An A-priori power analysis was conducted using G*Power (Faul, Erdfelder, Buchner, & Lang, 2009) to determine the minimum sample size for the correlations and regression analysis. Using a one-tailed bivariate correlational model with medium effect size (r = 0.30), and power set to 0.8, and p = 0.05, the required sample was 67. For general multivariate linear regression, using 6 independent variables, a medium effect size (f2) of 0.15, power of 0.8, and p = 0.05, the required sample was 98. As described below, four variables were associated with PF and were added to the regression equation. Using the same settings for a hierarchical regression, with 4 variables in set A and 6 in set B, G*power did not show an increase in the suggested sample size (however, Soper's 2022 calculator suggests a sample of 101; both G*power and Soper revealed that a general multivariate model with 10 independent variables requires 118 participants). The sample size in our regression analysis after pairwise deletions was 114, which falls within the suggested range (98–118).
Results
Descriptive statistics
All continuous measures were normally distributed (Kim, 2013). SPSS revealed one outlier on PF; given psychedelic experiences are highly subjective and to maximize power, we decided to retain that participant's data in the analyses.
Psychedelic consumption characteristics
The majority of participants reported taking a classic psychedelic at least 10 times in their life (58.1%). The two most common psychedelics were LSD (44.4%) and psilocybin (39.1%). Most participants characterized their dose as moderate (36.9%) or moderately high (37.3%) and consumed the substance orally (80.5%). The majority (60.1%) also indicated they were not under the influence of other substances (excluding caffeine and nicotine) during the psychedelic session that they held in mind while responding to the survey. Music was present for 86.8% of the sample. See Table 2.
Consumption characteristics
| Sample characteristics | N | Valid %a | Total %b | |
| Classic Psychedelic Experiences | ||||
| 1 time | 16 | 6.0% | 6.0% | |
| 2–4 times | 40 | 15.0% | 15.0% | |
| 5–10 times | 56 | 21.0% | 21.0% | |
| 10+ times | 155 | 58.1% | 58.1% | |
| Substance | ||||
| LSD | 118 | 44.4% | 44.2% | |
| Psilocybin | 104 | 39.1% | 39.0% | |
| Ayahuasca | 22 | 8.3% | 8.2% | |
| N,N-DMT, 5-Me0-DMT | 20 | 7.5% | 7.5% | |
| Mescaline | 2 | 0.8% | 0.7% | |
| Dose Characterization | ||||
| Low | 11 | 4.2% | 4.1% | |
| Moderate | 97 | 36.9% | 36.3% | |
| Moderately High | 98 | 37.3% | 36.7% | |
| High | 57 | 21.7% | 21.3% | |
| Route of Administration | ||||
| Oral | 211 | 80.5% | 79.0% | |
| Sublingual | 29 | 11.1% | 10.9% | |
| Smoked/Vaporized | 19 | 7.3% | 7.1% | |
| Other | 3 | 1.1% | 1.1% | |
| Under Influence of other Substancesc | ||||
| No | 158 | 60.1% | 59.2% | |
| Yes | 105 | 39.9% | 39.3% | |
| Presence of Music | ||||
| Yes | 223 | 86.8% | 83.5% | |
| No | 34 | 13.2% | 12.7% | |
Note. a. Valid % represents participants who responded to the item. b. Total % represents the 267 participants eligible for analyses. c. Under influence of other substances excludes caffeine and nicotine.
Study variable descriptives
Descriptive statistics of main study variables are in Table 3. For PF, the total score average is commensurate with “Agreed Somewhat” suggesting greater adaptability to new experiences and the ability to perceive multiple explanations or solutions for life events. Participant responses on decentering suggest that most participants appraised themselves as having some ability to separate from the self, and view their thoughts and emotions as temporary, instead of ruminating over them. Most participants generally agreed to having a mystical experience, a loss of sense of self (i.e., identity), disrupted ego-boundaries, and greater external connection during their only or most meaningful psychedelic experience. Additionally, most participants were able to realize aspects of their life that they had been previously unaware of such as life goals or life purpose and clarity around circumstances or events that had been holding them back. For comparisons of these means to prior studies see Table 4.
Descriptive statistics of main study measures
| M1 | SD | Scale range | Actual range | Skewness | Kurtosis | |||
| Statistic. | Std. error | Statistic. | Std. error | |||||
| Psychological Flexibility | 110.90 | 15.41 | 20–140 | 50–138 | −1.11 | 0.173 | 2.09 | 0.345 |
| Decentering | 45.14 | 8.92 | 13–65 | 21–63 | −0.45 | 0.155 | −0.19 | 0.309 |
| Mystical Experiences | 97.48 | 29.77 | 0–135 | 3–135 | −1.08 | 0.163 | 0.73 | 0.324 |
| Ego-Dissolution | 531.82 | 190.02 | 0–800 | 0–800 | −0.64 | 0.18 | −0.25 | 0.358 |
| Insight | 89.02 | 35.76 | 0–140 | 0–140 | −0.75 | 0.184 | −0.12 | 0.366 |
| Religious Salience | 18.79 | 10.45 | 5–35 | 5–35 | 0.011 | 0.189 | −1.47 | 0.376 |
Note. 1. Total scale mean.
Comparison of study measures with previous studies
| Construct | Measure (Author) | Current study | Previous studies |
| Psychological Flexibility | CFI (Dennis & Vander Wal, 2010) | M = 110.90 (SD = 15.41) | M = 103.05 (SD = 6.81) patients with opioid substance abuse following Quality of Life therapy (Khodarahimi, Ghadampour, Heidaryani, & Karami, 2020; α = 0.89) |
| Decentering | EQ (Fresco et al., 2007) | M = 45.14 (SD = 8.92) | M = 41.75 (SD = 7.29) ayahuasca participants 24 h following use (Murphy-Beiner & Soar, 2020; α = 0.84) |
| Mystical Experiences | MEQ (Barrett et al., 2015) | M1 = 3.61 (SD = 1.10) based on a scale from 0 to 5 | M1 = 2.82 (SD = 0.11) participants following 5-MeO-DMT use (Barsuglia et al., 2018) Mystical Experiences (α = 0.96); Positive mood (α = 0.90); Space/time (α = 0.93) |
| Ego-Dissolution | EDI (Nour et al., 2016) | M = 531.82 (SD = 190.02) | M = 480 (SD = 218.4) participants four weeks following an ayahuasca experience (Uthaug et al., 2018) |
| Insight | PIQ (Davis et al., 2020) | M = 89.02 (SD = 35.76) | M = 86.9 (SD = 45.9) cross-sectional study exploring insight in psilocybin and LSD users (Davis et al., 2021; α = 0.93) |
| Religious Salience | RS (Blaine & Crocker, 1995) | M1 = 3.95 (SD = 2.26) based on a scale from 1 to 7 | M = 4.481 (SD = 2.00) US adults, beliefs about supernatural messages via psychedelic use (Exline, Schutt, Pait, & Wilt, 2022; α = 0.95) |
Note. 1 Item means and Standard Deviations. Abbreviations: CFI = Cognitive Flexibility Inventory; EQ = Experiences Questionnaire; MEQ = Mystical Experiences Questionnaire; EDI = Ego Dissolution Inventory; PIQ = Psychological Insight Questionnaire; RS = Religious Salience Scale.
Associations between demographics and study variables
Correlations appear in Table 5. Age and income were significantly associated with PF such that as age and income increased, reports of PF increased. Additionally, the number of prior psychedelic experiences and religious salience were associated with greater PF. These socio-demographics were therefore included in the regression analyses as covariates. T-tests and ANOVAs were run on categorical demographics; no significant differences in PF emerged.
Correlation coefficients for study variables and covariates
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | |
| 1. Age | |||||||||||||
| 2. Edu. | 0.3** | ||||||||||||
| (162) | |||||||||||||
| 3. Inc. | 0.5** | 0.3** | |||||||||||
| (135) | (140) | ||||||||||||
| 4. Exp. | 0.3** | 0.0 | 0.2* | ||||||||||
| (164) | (168) | (141) | |||||||||||
| 5. Dose | 0.2** | 0.0 | 0.0 | 0.4** | |||||||||
| (164) | (168) | (141) | (263) | ||||||||||
| 6. RS | 0.2* | 0.0 | 0.0 | 0.1 | 0.1 | ||||||||
| (159) | (163) | (137) | (165) | (165) | |||||||||
| 7. Int. | 0.2** | 0.1 | 0.0 | 0.1 | 0.1 | 0.3** | |||||||
| (148) | (150) | (125) | (221) | (221) | (147) | ||||||||
| 8. CSI | 0.1 | 0.0 | 0.0 | 0.1 | 0.1 | 0.0 | 0.0 | ||||||
| (164) | (168) | (141) | (258) | (257) | (165) | (221) | |||||||
| 9. CSD | 0.1 | −0.1 | 0.1 | 0.1 | −0.1* | 0.0 | 0.0 | 0.2** | |||||
| (162) | (166) | (140) | (254) | (253) | (163) | (219) | (253) | ||||||
| 10. EQ | 0.1 | 0.1 | 0.2* | 0.3** | 0.2** | 0.3** | 0.2** | 0.1** | 0.2** | ||||
| (161) | (165) | (138) | (247) | (247) | (162) | (245) | (247) | (243) | |||||
| 11. ME | 0.1 | −0.1 | −0.0 | 0.3** | 0.3** | 0.3** | 0.3** | 0.1 | 0.1* | 0.3** | |||
| (158) | (162) | (137) | (224) | (224) | (159) | (223) | (224) | (220) | (222) | ||||
| 12. ED | 0.0 | −0.1 | −0.0 | 0.3** | 0.3** | 0.2** | 0.1 | 0.2* | 0.1 | 0.2** | 0.7** | ||
| (134) | (135) | (115) | 182) | (182) | (132) | (181) | (182) | (180) | (179) | (177) | |||
| 13. PIQ | 0.1 | −0.2* | −0.1 | 0.4** | 0.2* | 0.3** | 0.3** | 0.1 | 0.0 | 0.2** | 0.7** | 0.3** | |
| (151) | (156) | (131) | (174) | (174) | (154) | (173) | (174) | (171) | (171) | (170) | (141) | ||
| 14. PF | 0.2* | 0.1 | 0.3** | 0.3** | 0.1 | 0.3** | 0.3** | 0.2* | 0.2* | 0.6** | 0.2** | 0.2* | 0.2* |
| (154) | (157) | (133) | (197) | (197) | (154) | (196) | (197) | (194) | (194) | (191) | (160) | (162) |
Note. *p < 0.05 **p < 0.01; (2-Tailed). N values are listed in parentheses beneath correlations. Pairwise deletions were used.
Left Column Abbreviations. 1: Age; 2: Education Level; 3: Income; 4: Number of Previous Psychedelic Experiences; 5: Dose Characterization; 6: Religious Salience; 7: Intention; 8: CSI = Comfort/Safety going into the Experience; 9: CSD = Comfort/Safety during the Experience; 10: EQ = Decentering; 11: ME = Mystical Experiences; 12: ED = Ego Dissolution; 13: PIQ = Insight; 14: Psychological Flexibility.
Hypothesis testing
We tested the hypothesis that self-perceived meaningful intention, comfort/safety during the psychedelic experience, decentering, mystical experiences, ego-dissolution, insight, would be associated with PF. As predicted, the correlations reveal significant bivariate associations between PF and these variables, such that greater reports of these characteristics were associated with greater reports of PF.
We also examined if these results remained after controlling for demographics and consumption characteristics, and explored the relative contribution of each psychological process to PF when examined simultaneously. To do so, we ran an exploratory multivariate hierarchical regression analysis with PF as the outcome variable. All regression analysis assumptions were met (i.e., no multicollinearity, independence of residuals, variance of residuals are constant, normal distribution of residuals, no outlier bias per Cook's Distance).
The regression model was built as follows: age and income were added on the first block (model one), then religious salience (model two), followed by number of psychedelic experiences (model three), intention (model four), comfort/safety during the experience (model five), and then decentering, mystical experiences, ego-dissolution, and insight as a block (model six). The final model revealed that income, intention, and decentering were the only variables to remain significant. See Table 6.
Hierarchical multiple regression for psychological flexibility
| Variables | B | SE | β | t | p | R2 |
| Model 1 | ||||||
| Constant | 101.22 | 4.11 | 24.63 | <0.001 | ||
| Age | 0.03 | 0.14 | 0.02 | 0.19 | 0.851 | |
| Income | 3.20 | 1.03 | 0.31 | 3.11 | 0.002 | 0.088 |
| Model 2 | ||||||
| Constant | 94.86 | 4.40 | 21.56 | <0.001 | ||
| Age | −0.06 | 0.13 | −0.05 | −0.45 | 0.651 | |
| Income | 3.61 | 1.00 | 0.35 | 3.62 | <0.001 | |
| Religious Salience | 0.42 | 0.13 | 0.29 | 3.26 | 0.001 | 0.160 |
| Model 3 | ||||||
| Constant | 81.66 | 6.54 | 12.49 | <0.001 | ||
| Age | −0.13 | 0.13 | −0.09 | −0.96 | 0.338 | |
| Income | 3.36 | 0.97 | 0.33 | 3.45 | <0.001 | |
| Religious Salience | 0.39 | 0.13 | 0.26 | 3.08 | 0.003 | |
| Number of Psychedelic Experiences | 3.88 | 1.50 | 0.23 | 2.67 | 0.009 | 0.204 |
| Model 4 | ||||||
| Constant | 76.70 | 6.61 | 11.61 | <0.001 | ||
| Age | −0.20 | 0.13 | −0.14 | −1.49 | 0.140 | |
| Income | 3.63 | 0.95 | 0.36 | 3.82 | <0.001 | |
| Religious Salience | 0.29 | 0.13 | 0.19 | 2.23 | 0.028 | |
| Number of Psychedelic Experiences | 3.73 | 1.41 | 0.23 | 2.65 | 0.009 | |
| Intention | 1.27 | 0.46 | 0.24 | 2.74 | 0.007 | 0.248 |
| Model 5 | ||||||
| Constant | 69.42 | 7.67 | 9.05 | <0.001 | ||
| Age | −0.21 | 0.13 | −0.16 | −1.63 | 0.106 | |
| Income | 3.57 | 0.94 | 0.35 | 3.79 | <0.001 | |
| Religious Salience | 0.30 | 0.13 | 0.20 | 2.35 | 0.021 | |
| Number of Psychedelic Experiences | 3.67 | 1.40 | 0.22 | 2.63 | 0.010 | |
| Intention | 1.25 | 0.46 | 0.24 | 2.73 | 0.007 | |
| Comfort/Safety During Experience | 1.02 | 0.56 | 0.15 | 1.81 | 0.073 | 0.264 |
| Model 6 | ||||||
| Constant | 53.64 | 7.75 | 6.92 | <0.001 | ||
| Age | −0.15 | 0.12 | −0.11 | −1.25 | 0.215 | |
| Income | 2.79 | 0.88 | 0.27 | 3.16 | 0.002 | |
| Religious Salience | 0.16 | 0.13 | 0.11 | 1.25 | 0.213 | |
| Number of Psychedelic Experiences | 2.19 | 1.42 | 0.13 | 1.54 | 0.127 | |
| Intention | 0.87 | 0.44 | 0.17 | 1.99 | 0.049 | |
| Comfort/Safety During Experience | 0.47 | 0.53 | 0.07 | 0.89 | 0.377 | |
| Decentering | 0.73 | 0.15 | 0.43 | 4.97 | <0.001 | |
| Mystical Experiences | −0.03 | 0.07 | −0.06 | −0.41 | 0.682 | |
| Ego-Dissolution | 0.00 | 0.01 | 0.03 | 0.30 | 0.767 | |
| Insight | 0.01 | 0.05 | 0.02 | 0.16 | 0.870 | 0.384 |
Note. Adjusted R2 was used to determine contribution. Model 1 summary: [F (2, 112) = 6.47, p = 0.002, R2 = 0.09]; Model 2 summary: [F (3, 111) = 8.23, p < 0.001, R2 = 0.16]; Model 3 summary: [F (4, 110) = 8.30, p < 0.001, R2 = 0.20]; Model 4 summary: [F (5, 109) = 8.53, p < 0.001, R2 = 0.25]; Model 5 summary: [F (6, 108) = 7.80, p < 0.001, R2 = 0.26]; Model 6 summary: [F (10, 104) = 8.11, p < 0.001, R2 = 0.38]. (Total n = 114).
Discussion
We proposed that intention, comfort/safety during the experience, decentering, mystical experiences, ego-dissolution, and insight would be significantly associated with PF among users of classic psychedelics. The bivariate correlations showed that these relationships were significant and positive. After controlling for potential influences of demographics and consumption characteristics, and including all main study variables in the model simultaneously, results revealed that intention and decentering were the only hypothesized variables to retain significance. This is interesting to note given that comfort/safety during the experience, mystical experiences, ego-dissolution, and insight were individually associated with PF and speaks to the need to examine these characteristics together instead of separately. It is likely that characteristics of the psychedelic experience work together in their association with PF, or some might simply be more strongly associated with PF, rendering the other characteristics insignificant once they are added to the equation.
Forming a meaningful intention is likely a very important preparation technique for understanding the reason(s) for embarking upon a psychedelic experience in the first place and can be useful in surrendering to, accepting, or interpreting any challenging experiences that arise during the session (Wolff et al., 2020). Indeed, intentions that facilitate a shift in perspective suggest how setting a meaningful intention can influence PF.
Decentering was the only other characteristic to retain significance in the final regression model. The process of decentering allows individuals to create a space between their sense of self and any thoughts or emotions that arise during the psychedelic experience. During decentering, individuals may see the root for why they think or feel a particular way, which then provides an opportunity to view these thoughts, emotions, and experiences from another perspective, which may explain why decentering had the strongest association with PF. Without being able to step back, or detach, from one's thoughts, emotions, or beliefs, the characteristics of PF (e.g., openness, adaptation, and acceptance) would be more difficult to achieve and maintain. It seems decentering may well be the main path by which to achieve PF. Although one might argue that these two concepts are quite similar, especially given the overlap in cognitive focus, they are distinct constructs (e.g., the bivariate correlation shows 67% unique/33% shared variance between them).
Although intention and decentering were the only two variables to remain significant in the final regression model, it is likely that they, along with comfort/safety during the experience, mystical experiences, ego-dissolution, and insight, work together in their association with PF. Viewing the current study's results alongside other existing findings, there is likely a complex, reciprocal relationship among predictors of PF, which may be obscured by the cross-sectional design. It may be the case that there is a spiral or feedback loop in place that makes it difficult for these characteristics of the psychedelic experience to be parsed out without longitudinal models.
Limitations and future directions
There are several limitations to this study. One is the relatively small sample size given the number of variables in the regression model. While regressions are typically robust with small samples (e.g., Gavilanes, 2020), and our sample was within the range recommended to obtain reliable effects, replication in larger samples would further validate and bolster confidence in our findings. As previously noted, the current study is cross-sectional in nature, therefore firm conclusions regarding the direction of effects cannot be drawn. Future longitudinal designs, with larger samples, can disentangle the complex interactions among these variables as well as reveal patterns in how they might fluctuate.
Some methodological limitations include response bias and participants' ability to recall their psychedelic experience accurately due to time that passed or encountering new information regarding psychedelic substances. Most notable, however, is that the PF measure focused solely on cognitive aspects of this construct. Measure choice was made due to some analyses of the generally used PF scale in psychedelic users (Acceptance and Action Questionnaire II) that indicated it tends to reflect psychological distress more so than PF (e.g, Tyndall et al., 2019). However, the assessment for decentering also comprised mostly cognitively-focused items. Thus, it is not surprising that decentering was related to PF given this overlap in assessment. While the cognitive domain is a component of PF, and further understanding and replication of its association with elements of the psychedelic experience is warranted, we suggest that future research examine how psychedelic characteristics might predict other components of PF as described in the PFM, such as shifts in sense of self, values, or committed behaviors.
The current findings also suggest religious salience may be an important avenue for future research as it was significantly correlated with numerous characteristics of the psychedelic experience, suggesting that perceived importance of religion/spirituality may facilitate decentering, mystical experiences, ego-dissolution, and PF. However, this variable has rarely been explicitly studied as a predictor of outcomes in psychedelic research. One notable exception is a study by Neitzke-Spruill and Glasser (2018); they found that religious-identifying participants who set a religious intention reported significantly stronger mystical experiences with psychedelics. Taken together, these findings point to religious/spiritual salience as a promising area for future investigation.
Conclusion
The current study aimed to fill a gap in the literature by investigating the association between PF and various characteristics of the psychedelic experience including intention, comfort/safety during the experience, decentering, the mystical experience, ego-dissolution, and insight that could potentially serve as the mechanism of action between use of psychedelics and increased PF. While all were correlated with PF, regression results revealed intention and decentering remained significantly associated with PF after controlling for demographics and consumption characteristics. Results also revealed interesting significant correlations with religious salience which has not received much prior research attention. To further clarify predictors of PF, future research should employ longitudinal designs with larger samples, and a broader assessment of PF components.
Although classic psychedelics are illegal in many countries, psychedelic research has increased in the past decade, with both cross-sectional and random-control trial studies finding positive health outcomes such as addiction recovery, reduced PTSD, spiritual growth, and increased positive outlooks on life. Future research should continue to explore psychedelic experiences across the fields of psychology, neuroscience, religion and spirituality. By doing so, a larger picture can be developed to facilitate a fuller understanding of psychedelic use and well-being.
Acknowledgements
The current research stems from the first author's masters' thesis. Part of these results were presented at the Psychedemia Conference, Columbus Ohio (August 2022), with a travel grant from the Source Research Foundation. We thank the individuals who took the time to participate in this study and would also like to extend gratitude towards the thesis committee members for helpful feedback and support: Dr. Jon Horvitz and Dr. Teresa Lopez-Castro. The authors are also grateful to the anonymous reviewers who offered suggestions that strengthened this manuscript.
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