Most of the participants who received the psilocybin considered it to have produced one of the most spiritual experiences of their entire life. These participants produced significantly higher scores on measurements of mysticism, sacredness, transcendence, and ineffability. Furthermore, participants who received psilocybin were found to have had significantly higher levels of positive mood, peace, harmony, and happiness, more positive attitudes about life, and significant increases in altruistic social behaviors.
Psychedelics used by shamans and those who partake in their rituals alter brain function by decreasing cerebral blood flow and functional connectivity between the default mode network (DMN) and the frontal cortex. The DMN is a resting state network which plays a key role in daydreaming, metacognition, rumination, memory retrieval as well as reflection.
The ability psychedelics have in decoupling this network from its associated regions increases the flexibility of brain networks which in turn produces a more open communication among them. Psychedelic decoupling permits a freer operation of the medial temporal lobe structures and produces a consciousness that is based in somatic (body) awareness and subjective feeling states. This type of cognition occurs without the metacognitive ability for self-reflection provided by the frontal cortex.
A study in PLOS One, conducted by Palhano and colleagues titled “The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network,” used fMRI techniques to inspect the DMN during the psychedelic state induced by ayahuasca in 10 experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians and commonly used by shamans that is composed of a mixture of compounds which increases the transmission of serotonin and dopamine.
The researchers found that ayahuasca caused a significant decrease in activity through most parts of the DMN, some of which include the posterior cingulate cortex (PCC)/precuneus and the medial prefrontal cortex (mPFC). Functional connectivity within the PCC/precuneus decreased after ayahuasca intake. The researchers concluded that the altered state of consciousness induced by ayahuasca, like those induced by psilocybin, meditation, and deep sleep, is linked to the modulation of the activity and the connectivity of the DMN.
My clinical research currently explores activation of the DMN and endogenous opioid regulation in patients with fibromyalgia during meditative practices. A variety of endogenous opioid peptides (for example, endorphins, enkephalins, dynorphins, and endomorphins), similar to morphine and opium, are naturally produced by the body and are elicited by contemplative states and ritual activities. Both endogenous and exogenous opioids (that is, opium and morphine) have similar effects in engaging neurotransmitter networks that induce positive emotions and inhibit pain. Opioids activate the dopaminergic networks and induce feelings of euphoria, belongingness, and enhance stress tolerance.
Shamanistic activities can directly stimulate the release of these endogenous opioids through nighttime rituals, exposure to temperature extremes, self-inflicted wounds, and emotional manipulations that evoke fear. In turn, these visceral experiences can have significant impacts upon the sense of self/ego and personal narrative of an individual.
A case study by Santarpia and colleagues, published in the Journal of Humanistic Psychology titled “The narrative effects of shamanic mythology in palliative care,” investigated the therapeutic effects of narrative interventions in psycho-oncology. The authors found that shamanism sessions enabled their patient to produce a larger and more singular narrative about her end-of-life experience: from the initial narrative position of feeling “the acute consciousness of finiteness” to an emergent narrative position based on “consciousness of an interdependence/ interconnection in all human and spiritual relationships.”
Narrative therapy driven by shamanic practices not only affords the person an opportunity to process an experience but also to assist them in “meaning making.” A narrative that can be transformed and re-evaluated by shamanic ritual may be a promising means of empowering a patient with a sense of healing even when a cure is not in sight.
Shamanism must be explored further in order to determine how it effects the mind, the body, and the spirit. Based upon preliminary findings within the fields of molecular medicine, psycho-oncology, and contemplative neuroscience, it seems as if the scientific community is only at the beginning of discovering how shamanism can shape and even possibly heal our human condition in this century.
