Four Weekly Ayahuasca Sessions Lead to Increases in “Acceptance” Capacities : A Comparison Study With a Standard 8-Week Mindfulness Training Program, Joaquim Soler et al., 2018,

Four Weekly Ayahuasca Sessions Lead to Increases in “Acceptance” Capacities : A Comparison Study With a Standard 8-Week Mindfulness Training Program

Joaquim Soler, Matilde Elices, Elisabeth Dominguez-Clavé, Juan C. Pascual, Amanda Feilding, Mayte Navarro-Gil, Javier García-Campayo and Jordi Riba

Frontiers in Pharmacology, 2018, 9, 224.

doi: 10.3389/fphar.2018.00224


Background : The therapeutic effects of the Amazonian plant tea ayahuasca may relate to its ability to enhance mindfulness capacities. Ayahuasca induces a modified state of awareness through the combined action of its active principles: the psychedelic N,N-dimethyltryptamine (DMT) and a series of centrally acting b-carbolines, mainly harmine and tetrahydroharmine. To better understand the therapeutic potential of ayahuasca, here we compared the impact on mindfulness capacities induced by two independent interventions: (a) participation in four ayahuasca sessions without any specific purpose related to improving mindfulness capacities; and (b) participation in a standard mindfulness training course: 8 weeks mindfulness-based stress reduction (MBSR), with the specific goal of improving these skills.

Methods : Participants of two independent groups completed two self-report instruments: The Five Facet Mindfulness Questionnaire (FFMQ) and the Experiences Questionnaire (EQ). The MINDSENS Composite Index was also calculated, including those EQ and FFMQ items that have proven to be the most sensitive to meditation practice. Group A (n = 10) was assessed before and after the last of four closely spaced consecutive ayahuasca sessions. Group B (n = 10) was assessed before and after completion of a standard 8-week MBSR course.

Results : MBSR training led to greater increases in overall mindfulness scores after the 8-week period. MBSR but not ayahuasca led to increases in the MINDSENS Composite Index. However, the ayahuasca sessions induced comparable increases in the Non-Judging subscale of the FFMQ, specifically measuring “acceptance.” Improving this capacity allows for a more detached and less judgmental stance toward potentially distressing thoughts and emotions.

Conclusion : The present findings suggest that a small number of ayahuasca sessions can be as effective at improving acceptance as more lengthy and costly interventions. Future studies should address the benefits of combining ayahuasca administration with mindfulness-based interventions. This will allow us to investigate if ayahuasca will improve the outcome of psychotherapeutic interventions.

Keywords : ayahuasca, mindfulness, acceptance, Non-Judging, human



In recent years there has been a renewed interest in the potential use of psychedelics for the treatment of different psychiatric conditions (Sessa, 2005; Mithoefer et al., 2016). One of the substances that have gained attention is ayahuasca; a tea obtained from the mix of Banisteriopsis caapi with Psychotria viridis (Rubiaceae) or Diplopterys cabrerana (Malpighiaceae) (McKenna et al., 1984). The b-carboline alkaloids present in ayahuasca [i.e., harmine, tetrahydroharmine (THH), and harmaline] show monoamine-oxidase (MAO) inhibiting properties (Buckholtz and Boggan, 1977b) and also serotonin reuptake inhibition (THH; Buckholtz and Boggan, 1977a). The leaves of P. viridis and D. cabrerana contain N,N-dimethyltryptamine (DMT), an alkaloid that is also extracted into the ayahuasca brew during the infusion process. DMT is the main psychotropic agent of ayahuasca, and possibly the responsible for the dream-like experience induced by the tea. This modified state of consciousness is characterized by the presence of visual imagery and the recollection of highly emotional autobiographic memories (Riba et al., 2001). On a molecular level, DMT has affinity for 5-HT2A and 5-HT1A binding sites, where it acts as an agonist or partial agonist (Riba et al., 2001; Carbonaro et al., 2015). Although DMT has been regarded as the primary ayahuasca compound acting on the CNS, recent research has shown that the b-carbolines may also have a relevant contribution to the overall effects of ayahuasca in the brain. Specifically, harmine, THH, and the harmine metabolite harmol, stimulate adult neurogenesis in vitro (Morales-García et al., 2017). Traditionally, ayahuasca has been consumed for ritual and medical purposes in the Amazon Basin. Today its use has spread worldwide, encouraging research on its potential therapeutic effects (Domínguez-Clavé et al., 2016). Compared to non-users, habitual ayahuasca consumers show lower hopelessness (Santos et al., 2007) and depression levels, and higher scores on certain personality traits like agreeableness and openness (Barbosa et al., 2016). Experimental studies of acute ayahuasca administration to healthy volunteers have found that ayahuasca targets key nodes of the default mode network (Valle et al., 2016; Sampedro et al., 2017) that are associated with higher self-consciousness and pathological ruminations (Vogt and Laureys, 2005). Additionally, data shows increased blood flow in several brain regions implicated in cognitive control, emotion regulation, and memory (Riba et al., 2006; Sanches et al., 2016). Recent clinical studies on its utility as an adjunct to psychological interventions have demonstrated therapeutic benefits in treatment-resistant depression (Osório Fde et al., 2015; Dos Santos et al., 2016; Sanches et al., 2016) and substance abuse (Fábregas et al., 2010; Thomas et al., 2013).

In a previous work by our group (Soler et al., 2016), we argued that the therapeutic effects of ayahuasca might be related to increases in mindfulness-related capacities. Mindfulness entails a focus on the present experience and reaching a state of non-judgmental awareness, enhanced curiosity and openness (Kabat- Zinn, 1990; Bishop et al., 2004; Baer et al., 2006). These qualities can be considered from a dimensional trait perspective, but can also be fostered through meditative practice. In the last three decades there has been a proliferation of mindfulness-based interventions designed to teach individuals how to maximize these skills. Probably the most commonly used intervention is the Mindfulness-Based Stress Reduction (MBSR; Kabat-Zinn, 1990) approach, an 8-week program that has been widely applied to deal with a number of medical and psychiatric conditions. MBSR focuses on the cultivation of mindfulness through formal meditation practices (i.e., body scan, sitting meditation and yoga), and on the integration of mindfulness-principles into everyday activities (Kabat-Zinn, 1990). In our previous study (Soler et al., 2016), we assessed mindfulness-related capacities before and after one dose of ayahuasca, finding that ayahuasca intake led to increases in three core mindfulness facets : decentering, defined as the capacity to observe one’s thoughts and inner experiences in a detached manner (Fresco et al., 2007); Non-Judging and Non-Reacting, defined, respectively, as the ability to take non-judgmental and non-reactive stances toward emotions, thoughts and experiences in general (Baer et al., 2006). Moreover, in a subsequent study using magnetic resonance imaging (MRI) we reported that post-acute metabolic and connectivity changes in the brain after a single ayahuasca session were associated with maintained elevations in the nonjudgmental attitudes 2 months later (Sampedro et al., 2017).

Together, the above data indicates that traditional mindfulness training techniques are not the only pathway to foster mindfulness capacities. They further suggest that ayahuasca intake may attain analogous results (Soler et al., 2016). However, the specific domains targeted by either approach have not been assessed. Here, we conducted an exploratory-comparison study in order to evaluate the similarities and differences of the two approaches. Specifically, we compared the impact on mindfulness scores of: (a) participation in four consecutive ayahuasca sessions without the specific purpose of improving mindfulness capacities; and (b) participation in a standard mindfulness training course (8 weeks MBSR), with the specific goal of improving these skills. We hypothesized that both interventions would result in significant improvements in mindfulness capacities. However, given the lack of previous research comparing these two interventions hypotheses in regards to changes in specific-mindfulness facets were not made.