Ayahuasca improves emotion dysregulation in a community sample and in individuals with borderline-like traits

Ayahuasca is a traditional Amazonian psychoactive brew prepared from Banisteriopsis caapi (containing β-carboline monoamine oxidase inhibitors such as harmine and tetrahydroharmine) and Psychotria viridis (which contains N,N-dimethyltryptamine, DMT). Orally, DMT is rendered active by the β-carbolines' MAO-inhibiting action. Acute ayahuasca exposure produces a conscious, dream-like state marked by introspection, visual phenomena and heightened emotion; pharmacological actions implicated include 5-HT2A/5-HT1A agonism by DMT and interactions with the sigma-1 receptor, which may promote neural plasticity. Prior studies have reported beneficial effects of ayahuasca on depression, anxiety, substance use and wellbeing, and some work has suggested that a single session can enhance mindfulness-related capacities such as decentering, non-judging and non-reactivity—capacities that overlap with those trained in mindfulness-based interventions. The present study, led by Domínguez-Clavé and colleagues, set out to evaluate whether ayahuasca alters emotion regulation (ER) and mindfulness-related capacities in a community sample. A secondary aim was to explore these effects in a subgroup of participants exhibiting borderline personality disorder (BPD)-like traits, given that emotion dysregulation is central to BPD and that improvements in decentering and mindfulness are therapeutic targets in this population. The study therefore tested pre-to-24-hour-post changes on validated self-report measures of ER, mindfulness facets and decentering in volunteers attending naturalistic ayahuasca ceremonies.

This was an observational, within-subjects study of 45 volunteers recruited from three ayahuasca-using communities in the province of Barcelona. Ceremonies involved 20–25 attendees and participants consumed consecutive ayahuasca doses spaced by around 1 hour; procedural and ritual details varied slightly across groups but assessment procedures were identical. Questionnaires were completed shortly before the ceremony (baseline) and readministered 24 hours after ayahuasca intake. Participation was voluntary, written informed consent was obtained, and the protocol was approved by the Sant Pau Hospital Ethics Committee. Participants were divided into two subgroups using the McLean Screening Instrument for BPD (MSI-BPD): a BPD-like group scoring ≥ 5 (n = 12) and a non-BPD group scoring < 5 (n = 33). The authors explicitly used the lower cutoff of 5 to identify individuals with BPD-like traits rather than to diagnose BPD. Most participants had prior ayahuasca experience, while about one-third were naïve. Outcome measures included the Difficulties in Emotion Regulation Scale (DERS; 28 items, five subscales: emotional awareness, lack of clarity, emotional non-acceptance, emotional interference, lack of control), the Five Facet Mindfulness Questionnaire–Short Form (FFMQ-SF; 24 items assessing observing, describing, acting with awareness, non-judging, non-reacting), and the Experiences Questionnaire (EQ; 11-item decentering measure). The MINDSENS composite index, combining EQ and sensitive FFMQ items, was also calculated. The MSI-BPD was used for subgrouping. For analysis, sociodemographic comparisons used paired t tests or chi-square tests as appropriate. Missing item data were mean-imputed when < 20% of items were missing per scale (this affected < 5% of questions overall). Changes before versus after ayahuasca were tested primarily with multivariate ANOVAs for FFMQ and DERS subscales and univariate ANOVAs for EQ and MINDSENS, supplemented by two-way repeated measures ANOVAs to evaluate time and time×group interaction effects. Partial eta squared (η2) values were reported as effect-size estimates and p < 0.05 was considered significant. The extracted text indicates no acute-effect instruments were administered during the ceremonies and that the assessment was intentionally minimal to avoid interfering with participants' experiences.

Sample characteristics: Forty-five individuals (27 female, 18 male) took part, with a mean age of 39.89 years. The BPD-like subgroup (n = 12; 7 female, 5 male) had a higher mean age (43.58) than the non-BPD subgroup (mean 39.89; p = 0.04) and had greater prior ayahuasca experience. The MSI-BPD mean scores differed as expected between groups (BPD-like 6.27, SD = 1.34; non-BPD 1.52, SD = 1.48; p < 0.025). The extracted text reports a between-group baseline difference for the DERS lack of control subscale (p = 0.10); the p-value given is above conventional significance thresholds, so the report is ambiguous regarding conventional significance. Pre–post effects (whole sample): Two-way repeated measures ANOVA identified significant main effects of time on several outcomes. On the DERS, scores decreased significantly for emotional non-acceptance (p < 0.01), emotional interference (p < 0.05), and lack of control (p < 0.01). For the FFMQ, significant increases were observed on observing, acting with awareness, non-judging and non-reacting (all p < 0.01), while describing did not change (p > 0.05). Decentering (EQ) and the MINDSENS index both increased significantly (p < 0.01). The only reported time×group interaction was for the DERS lack of control subscale (p = 0.024), indicating group-dependent change on that measure. Within-group findings: In the non-BPD group (n = 33), one-factor ANOVAs indicated significant pre–post improvements on DERS emotional non-acceptance (large effect, η2 = 0.37), emotional interference (medium effect, η2 = 0.15) and lack of control (large effect, η2 = 0.24). No changes were observed for lack of clarity or emotional awareness. On the FFMQ, the non-BPD subgroup showed marked gains on observing (η2 = 0.63), acting with awareness (η2 = 0.24), non-reacting (η2 = 0.20) and non-judging (η2 = 0.28); describing did not change. EQ decentering increased with a medium effect (η2 = 0.16) and MINDSENS showed a large effect (η2 = 0.25). In the BPD-like subgroup (n = 12), one-factor ANOVAs showed significant pre–post reductions on DERS emotional interference (small–medium effect, η2 = 0.08) and lack of control (medium effect, η2 = 0.12). No significant pre–post changes were found for the other DERS subscales, any FFMQ subscales, EQ decentering or MINDSENS in this subgroup. The authors note that non-parametric Wilcoxon paired tests yielded some additional significant findings (for example, in FFMQ non-judging, non-reacting and observing), but these were not confirmed in the ANOVA—an outcome the authors attribute to the small size of the BPD-like subgroup. Finally, none of the participants reported adverse psychopathological effects related to the ayahuasca sessions.

Domínguez-Clavé and colleagues interpret their findings as the first evidence that a single ayahuasca session can positively influence emotion regulation, extending prior work on ayahuasca's benefits in affective and substance-use disorders. They emphasise that emotion dysregulation underlies many psychiatric conditions, notably BPD, and that therapies targeting ER (for example, emotion-regulation therapy and other psychotherapeutic approaches) focus on contact with and acceptance of emotions. In the present sample, improvements in ER were most robust in participants without BPD-like traits, with significant reductions in emotional non-acceptance, emotional interference and lack of control. The BPD-like subgroup also showed reductions in emotional interference and lack of control, but effects were smaller and fewer measures reached significance—an outcome the authors suggest may reflect limited statistical power. The researchers additionally report that ayahuasca enhanced several mindfulness-related capacities, including decentering, non-judging and non-reacting, and unexpectedly produced increases in the attention-related FFMQ facets observing and acting with awareness. They compare these changes to those produced by mindfulness-based interventions and note convergence with earlier studies that found single-session or short-course effects on acceptance and decentering. The authors propose that ayahuasca might augment attentional and acceptance capacities that are central to therapeutic change and could be combined with psychological interventions such as dialectical behaviour therapy or mindfulness training to enhance outcomes. The paper highlights several limitations acknowledged by the investigators. Chief among them is the uncontrolled, exploratory design in a convenience sample of community participants rather than a formal clinical trial in diagnosed patients; the BPD-like subgroup did not constitute a clinically diagnosed BPD sample. Most participants had prior ayahuasca experience, although about one-third were naïve, and no instrument was used to quantify acute subjective effects during the sessions. The small size of the BPD-like subgroup limits confidence in subgroup comparisons, and the authors note that placebo or expectancy effects cannot be ruled out. Given these caveats, they call for further research using larger samples, clinical populations, longer follow-up, comparisons of naïve versus experienced users, and designs capable of addressing placebo effects. Clinically, the authors tentatively suggest that ayahuasca could be considered as a complementary tool to enhance ER and mindfulness capacities, but stress the need for more rigorous evidence before therapeutic recommendations can be made.

The authors conclude that ayahuasca may acutely improve both emotion regulation and mindfulness-related capacities, findings that could have therapeutic relevance across several mental disorders. While acknowledging controversy about using dissociative or psychoactive interventions in populations with BPD, the observed benefits in individuals with BPD-like traits support further research to evaluate ayahuasca's potential role in clinical practice.