Effects of ayahuasca on gratitude and relationships with nature: An open-label, naturalistic study

Classic serotonergic psychedelics, including DMT which is the primary psychoactive component in the ayahuasca brew, have attracted renewed scientific and public interest because clinical trials pairing these drugs with psychotherapeutic support have reported therapeutic and prosocial effects. While earlier work has documented clinical improvements (for example in depression and substance use) and personality shifts such as increased openness and feelings of connection, several social and personality domains reported anecdotally after psychedelic use—specifically gratitude and relationships with nature—have been comparatively understudied. Aday and colleagues designed a naturalistic, open‑label, within‑subjects study to address this gap by measuring changes in gratitude, nature relatedness, and a related construct termed nature appreciation before and after attendance at an ayahuasca retreat. The investigators also tested whether acute subjective experiences during the most intense ayahuasca session—mystical‑type experience, awe, and ego dissolution—predicted post‑acute changes, and examined baseline predictors such as age and prior psychedelic use.

Design and setting: The study used an open‑label, naturalistic, within‑subjects design conducted at Soltara Healing Center, an all‑inclusive ayahuasca retreat in Puntarenas Province, Costa Rica. Participants completed surveys one week before the retreat (T1), one week after the retreat ended (T2), and one month after the retreat (T3). Acute subjective measures referencing each participant's most intense ayahuasca session were collected at T2. Participants and intervention: Attendees registered for the retreat were invited to participate. Inclusion requirements included being at least 18 years old and completing a medical intake that screened out contraindicated psychiatric disorders (for example schizophrenia or bipolar disorder), contraindicated medications (for example lithium), and certain medical conditions (for example heart ailments). Retreat stays ranged 5–12 nights, and participants took part in 2–7 ayahuasca ceremonies (mean = 3.67, SD = 0.85) led by Shipibo curanderos. The retreat context included meals, accommodation, access to natural grounds, and optional recreational activities such as yoga and hiking. Measures and timing: Baseline demographics and lifetime psychedelic use were collected at T1. The main outcome measures administered at T1, T2, and T3 were a multifaceted gratitude scale (AS, analysed by facet and total score), the NR‑6 (a short nature relatedness scale), and an APR measure of nature appreciation. Acute measures collected at T2 (referenced to the most intense session) were the MEQ30 (mystical‑type experience questionnaire), the AWE‑S (awe scale), and the EDI (ego dissolution inventory). Participants completed surveys online via Qualtrics. Sample and attrition: Seventy‑seven participants completed the baseline survey. Sixty‑five (84% of baseline) completed the one‑week post survey, and 55 (71% of baseline) completed the one‑month follow‑up. One participant who did not partake in any ceremonies was excluded, leaving a final analysed sample of N = 54 (mean age = 41.17, SD = 11.24; 24 female). The sample was highly educated (88.9% college degree or higher), majority non‑Hispanic white (74.1%), and skewed toward higher income (38.9% > $125,000/year). A wide range of prior psychedelic experience was reported. Data analysis: Changes over time in AS total and its eight facets were tested with a 3 × 8 repeated‑measures ANOVA (Time × Facet). NR‑6 and APR totals were each analysed with one‑way repeated‑measures ANOVAs across the three time points. Relationships between acute subjective measures (MEQ30, AWE‑S, EDI) and change scores at one week (∆1 = T2 − T1) and one month (∆2 = T3 − T1) were examined using Pearson correlations. The investigators reported effect sizes and conducted planned pairwise comparisons where applicable.

Sample and retention: From 77 participants at baseline, 65 completed the one‑week follow‑up and 55 completed the one‑month follow‑up; after excluding one person who did not partake in ceremonies, analyses used N = 54. Participants attended on average 3–4 ceremonies during their retreat. Gratitude (AS): The repeated‑measures ANOVA for AS showed a significant main effect of Time (F(1, 53) = 34.97, p < .001, ηp2 = 0.40). Planned comparisons indicated AS total scores at one week (T2) and one month (T3) post‑retreat were significantly higher than baseline (T1), while T2 and T3 did not differ from one another. The main effect of Facet was also significant (F(1, 53) = 709.19, p < .001, ηp2 = .93), with every facet increasing at T2 and T3 compared to baseline. A Time × Facet interaction (F(1, 53) = 5.68, p < .001, ηp2 = 0.10) reflected that the ritual and interpersonal facets showed particularly clear increases at T2 and T3 versus baseline. Change in gratitude did not correlate with the number of ayahuasca sessions attended (r = .03, p > .05), and the authors reported no evidence of attrition bias. Acute subjective measures of awe (AWE‑S) and mystical‑type experience (MEQ30), but not ego dissolution (EDI), were weakly to moderately correlated with one‑week and one‑month increases in AS total scores. Nature relatedness (NR‑6) and nature appreciation (APR): For NR‑6, Time had a significant effect (F(1, 53) = 26.27, p < .001, ηp2 = 0.33): one‑week and one‑month scores were higher than baseline and did not differ from each other. APR exhibited a comparable pattern (F(1, 53) = 31.79, p < .001, ηp2 = 0.38), with T2 and T3 exceeding T1 and no difference between T2 and T3. As with gratitude, AWE‑S and MEQ30—but not EDI—showed weak correlations with changes in NR‑6 and APR. Mystical‑type experiences and baseline predictors: Using a criterion of scoring ≥ 60% on each MEQ30 subscale to define a "complete mystical‑type experience," 37 of 54 participants (68.52%) met that threshold. Regarding baseline predictors of acute effects, age was negatively correlated with MEQ30 scores (r = −.34, p = .010) and with AWE‑S scores (r = −.39, p = .004), but not with EDI (r = −.18, p = .140). Lifetime history of psychedelic use was not significantly related to acute MEQ30 (r = .11, p = .424), AWE‑S (r = .05, p = .703), or EDI (r = .11, p = .388) scores.

Aday and colleagues report that participants who attended an ayahuasca retreat showed sustained increases in gratitude, nature relatedness, and nature appreciation at both one week and one month after the retreat, relative to baseline. Acute reports of mystical‑type experience and feelings of awe during the most intense ayahuasca session predicted these post‑acute increases, whereas ego dissolution did not. The findings extend prior work with other psychedelics by demonstrating similar post‑acute changes following ayahuasca and by including a measure of nature appreciation that had not been used in previous psychedelic studies. The authors interpret the correlations between awe, mystical experience, and subsequent increases in gratitude and nature‑related constructs as consistent with a possible mechanism in which intense, awe‑provoking experiences create meaningful memories that elevate gratitude and foster a stronger bond with nature. They note that awe and mystical‑type experience were very strongly correlated in their data (r = .86, p < .001), which may reflect overlapping phenomenology in this setting. Several limitations are acknowledged. The open‑label, uncontrolled, naturalistic design precludes causal attribution to pharmacology alone, and the retreat context included non‑pharmacological influences (for example, access to nature, yoga, social interactions) that could have contributed to the observed changes. The sample was demographically homogeneous (high education and income, majority non‑Hispanic white), limiting generalisability. The authors also remark on the practical difficulty of double‑blind trials with psychedelics given their salient acute effects. Other limitations include the variable number of ceremonies per participant and reliance on self‑report rather than behavioural or observer measures. For future research, the investigators recommend incorporating blinded controlled designs where feasible, longer follow‑up intervals to assess durability of change, behavioural and third‑party measures of gratitude and pro‑environmental behaviour, and mediation analyses to test whether prosocial shifts contribute to clinical improvements seen in other psychedelic studies. They also highlight strengths of the current study—adequate power, good retention, multiple follow‑ups, ecological validity, and use of validated multi‑facet measures—and conclude that their results provide preliminary evidence that ayahuasca‑occasioned mystical experiences and awe are associated with sustained increases in gratitude and connection to nature, with possible implications for mental health and pro‑environmental behaviour. The authors emphasise the need for further well‑powered research to address the noted limitations.