Fast Tracking the Road to Zen:
Exploring the Parallels Between the Neural Mechanisms Underlying Regular Meditation and the Psychedelic Experience
Author: Alyssa Swiderski
Could a tiny pill offer the same psychological benefits as years of meditation practice? This idea is now being explored as psychedelics are making a comeback in the world of modern psychiatry. Meditation focuses on building awareness of our thoughts or psychical surroundings and practicing acceptance. Over time, this shifts the way in which the mind responds to stress. It’s hard to find a psychologist or physician who doesn’t acknowledge the potential of meditation or mindfulness in improving mental health. However, researchers are now exploring a new idea: what if the same mental shift could happen in just a few hours?
Psychedelics are psychoactive substances capable of inducing “trips” - alterations of mental state, affecting mood, thinking, and perception (Nichols, 2016). Psychedelics have captivated experts with several studies investigating their effectiveness and safety in treating mental illnesses including anxiety, depression, and addiction (De Gregorio et al., 2021). This interest stems at least partly from their ability to stimulate existential experiences that have lasting psychological impacts (Griffiths et al., 2006).
Both regular meditation and psychedelics share the ability to produce therapeutic effects in populations with mental illness. Here we explore the parallels that can be drawn between their effects on the brain.
GABA and Serotonin: The Brain’s Relax and Feel Good Chemicals
Gamma-aminobutyric acid (GABA) is the brain's primary “calming chemical”. It signals the body to relax and calm brain activity, helping to reduce stress and anxiety. In a study analyzing blood flow in the brain of Buddhist meditators, researchers found higher levels of GABA in the prefrontal cortex (PFC), the area of the brain that regulates thoughts, emotions, and actions (Newberg & Iversen, 2003). Similarly, animal studies show that psychedelics also boost levels of GABA in the PFC (Wojtas et al., 2022). This implies that meditation and psychedelics could tap into the same brain pathway to induce calming effects.
Serotonin is known as the brain’s “feel-good” chemical because it helps regulate mood and emotions. A study showed that in people who regularly meditated, serotonin levels in urine were much greater than those who did not meditate (Bujatti & Riederer, 1976). Levels of serotonin increased even more directly following meditation practice (Bujatti & Riederer, 1976). Psychedelics work by activating the serotonin system in the brain, and potentially mimicking the effects of this natural chemical. This may explain the shared mood enhancing effects of both meditation and psychedelics.
The Default Mode Network: The Ego Centre of our Brain
The default mode network contains the parts of the brain that are activated when the mind is at rest, including when you are daydreaming, thinking about yourself, reflecting on the past or picturing your future. It is like the “ego centre” of the brain. The communication between parts of this brain network is often disrupted in individuals with a range of mental health conditions such as anxiety and depression (Coutinho et al., 2016). With the default mode network in overdrive, it can lead to excessive negative thinking or worry, distress, or self-criticism. In mindfulness meditation we help our brain deactivate this network and break habits of self-focused thinking (Garrison et al., 2015). Interestingly, brain imaging studies show that psychedelics create lasting changes in the way the default mode network communicates (Madsen et al., 2021). By quieting this network, it diminishes this “ego centre” and we lose our preoccupation with ourselves, decrease negative self-focused thought, rumination, and create more room for positive outwardly thinking!
Functional connectivity is a term used to describe communication happening between different areas of the brain. In individuals suffering from mental illness, “cross-talk” between brain regions working to process emotions is usually weaker. Meditation could help to strengthen these connections and help people to better regulate their emotions (Hölzel et al., 2013). Functional magnetic resonance imaging (fMRI), shows more cross-talk between these key regulatory regions after psychedelic use, a finding that also correlates with improvements in symptoms of depression (Mertens et al., 2020; Stoliker et al., 2024). Not only specific to these regions, communication increases between various regions that do not regularly interact under normal conditions (Carhart-Harris et al., 2012). By temporarily effecting the brain’s communication systems, psychedelics could make the brain more flexible, allowing for new perspectives and patterns of thought.
Although the meditation and psychedelic use could seem worlds apart, they may intersect more than we think. By acting on similar networks and regions in the brain, both may be involved in emotional regulation and mood. However, while much remains to be learned, these findings highlight the brains flexibility and its potential to be reshaped opening new doors for the treatment of mental disorders.
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