This study acquired a wireless EEG in naturalistic environment, as a tool for capturing brainwave patterns during consumption of a N,N-Dimethyltryptamine (DMT). The results unveiled the profound impact of this potent psychedelic drugs on theta oscillations in human brain.
DMT have piqued the curiosity of both the general public and researchers for its influence on mental health and wellbeing. Although its potential therapeutic properties are gaining attention, the neurological workings remain a mystery.
The inner workings of psychedelics, DMT in focus here, are multifaceted. They appear to engage many brain regions, inducing distinct EEG shifts.
This study suggests a strong link between specific EEG bands and the type of experiences one might have on DMT. To observe the influence of ayahuasca on the participants brain, they recorded EEG in naturalistic environment.
The study showed negative correlation between the baseline theta band power fluctuations, and the conscious experience reported by the subjects, indexing feelings of unity and transcendence.
Wireless EEG in naturalistic environment
Researchers recruited a group of DMT users passionate about probing their own consciousness. These participants were not casual users but were deeply intrigued by the DMT experience.
35 participants (7 females, average age 33) with varying DMT and ayahuasca experiences were recruited. They needed at least two prior encounters with these substances. Requirements were a 24-hour drug-free period before the study, and willingness to use DMT in front of the research team.
Participants used DMT as they typically would, within their preferred settings and were set-up with the wireless EEG the naturalistic environment.
This unique approach stands apart from the usual controlled lab settings. It brings forth its own set of advantages. The primary goal was to discern changes in EEG spectral power due to DMT and tie these changes to conscious experiences.
EEG recording procedure
Before taking DMT, participants had their EEG measured with eyes open and closed for 5 minutes each. Once DMT was given, EEG recordings began as they exhaled, continuing until they fell back to their normal state. Each run lasted around 6 minutes.
Psychometrics questionnaires
Before their DMT session, participants filled out surveys about anxiety levels and their mindset.
After DMT, they answered questions on altered states, mystical experiences, and near-death feelings. They also evaluated how their environment and interactions influenced their experience. Both before and after DMT, they took personality, anxiety, and absorption tests.
Comparing DMT’s Impact on EEG Source and Scalp Levels
To estimate sources (Figure below) during DMT consumption, researchers compared them to eyes closed condition. Compared to eyes closed, DMT consumption revealed posterior increases in delta power.
Theta band had similar but milder changes. The alpha band showed opposite effects. Alpha power decreased in occipito-temporal regions under DMT.
Beta power rose in posterior areas and dropped in prefrontal regions. Gamma power increased in occipital, parietal, and temporal areas with DMT.
These findings align with previously reported findings on source localisation during DMT inhalation. Nonetheless, but notable differences emerged in theta and beta bands.
The change in baseline theta oscillations is especially intriguing, hinting at their potential role in evoking mystical experiences.
Compounds like DMT majorly interact with the serotonin 5-HT2A receptors in our brains. This specific targeting could be pivotal in shaping the profound subjective experiences these substances usher in.
Correlation between theta oscillations with Conscious Experience
This study investigated the correlations between spectral power and survey subscales. Initial scalp-level analysis showed negative correlation between theta power and unity, mysticism and transcendence.
Importantly, this finding holds only for the theta band. Baseline theta power demonstrated a stark negative correlation with specific conscious experiences post-DMT. Reported finding was consistent across specific electrodes and mirrored the scalp findings.
This finding confirmed that DMT’s effects weren’t just neurological. They had a direct bearing on participants’ conscious experiences.
Predictive Models can estimate individual response to DMT
Using machine learning, the study aimed to predict subjective experiences based on EEG patterns. These models showed the potential to gauge an individual’s response to DMT based on their resting neural activity. This study proposed that the theta oscillations can predict the mystical experiences induced by DMT.
Conclusion
This study pioneers EEG in naturalistic environment for predicting psychedelic effects from initial neurophysiological data. While their therapeutic value remains debated, it’s linked to the conscious state during the psychedelic experience. Future research may correlate specific experiences with therapeutic benefits.
The challenge lies in crafting desired effects, necessitating in-depth exploration of baseline psychological and neural responses to these drugs.
The original publication source: https://www.frontiersin.org/articles/10.3389/fpsyt.2021.720066/full#B71
