When ketamine enters the bloodstream, it quickly travels to the brain and causes a temporary alteration in the level of consciousness. The default mode of thinking and perceiving is interrupted, and a radically different awareness of the world develops. The effects of ketamine on the brain and body wears off very quickly, and all patients return to baseline. Remarkably, the benefits of the treatments have been shown to last. It is believed that the sustained symptom improvements continue after the treatment is due to the shifting of connections within the brain and also from insight gained. A similar lasting benefit has been established in meditation, breathwork, yoga and other practices that induce new pathways in the brain.
When administered rapidly at a relatively high dose all at once, ketamine induces general anesthesia which is like a state of deep sleep. However, at a slower and lower dose infusion, the brain enters a state of aroused imagination and dissociation from the body. The senses such as sight, hearing, and proprioception (the sense of body positioning and balance) are altered. This allows the “mind’s eye” to hyperfocus on a dreamlike psychedelic inward landscape.
Many patients have described the psychedelic effects of ketamine as:
- A sacred mystical journey that enables connection with the divine;
- A flossing or deep scrubbing of the mind;
- A feeling of consciousness occurring outside the brain as if mind is separate from matter;
- An experience of floating from up above and looking back down on the body;
- The experience of ego or even physical death and having the feeling of euphoria or acceptance; a connection with ancestry; the experience of deep empathy for other individuals or beings; and developing the ability to revisit a previous trauma but not experiencing the pain that typically follows.
These experiences are beyond logic but communicate a sense of a deep and universal “truth” that is beyond words. The psychedelic experience can disintegrate the perception of the physical world, while maintaining conscious awareness. Then as you start to return to the normal waking and rational thought, you notice different patterns in your surroundings and develop a slightly new way of seeing. The world remains the same, but you the viewer have transformed, infused with a greater sense of wisdom. This is a type of insight learning that contrasts with the fact-based declarative learning where information is memorized. Insight is an unconscious enhancement of your awareness, where you are somehow changed, you feel different, there is a sense of skills being gained, but you struggle to explain exactly how.
These psychedelic landscapes induced by ketamine can be visited during deep states of meditation by experienced practitioners. In essence, ketamine should be thought of as medication enhanced meditation. While in this enhanced state, it stimulates or strengthens connections of the brain to talk to other areas of the brain that normally do not communicate. Many theories of mood disorders such as depression and chronic pain are caused by neural communication barriers where the person is stuck in the loud cross talk between two stressed out brain areas that manifest negative thought patterns, cravings, flashbacks to previous traumatic memories or an amplified sense of pain. During a state of medication enhanced meditation, an elevated state of consciousness and brain activity is achieved, which lowers the drawbridges and opens guard doors of the mind, allowing new perspectives and more positive processing of information.
Yet ketamine produces a brain state very distinct than the calm, focused practice of meditation. Ketamine itself works in a complicated and non-specific manner. We know that it binds to and reduces activity or inhibits the N-methyl-D-aspartate (NMDA) receptor. The NMDA performs a wide variety of functions in the brain. It is believed that ketamine blocks this receptor at “inhibitory interneurons,” which normally serve as the “breaks” to slow down and allow the brain to process information in an orderly manner. When the breaks are released, consciousness becomes disinhibited, and a more wide-spread activation of the brain occurs, which why a person feels dissociated from the body.
This momentary enhancement of consciousness stimulates the production of proteins in brain cells, particularly at nerve endings. Brain cells sprout little protein spikes called dendrites that form connections called synapses with other brain cells. So, when the music is over and the ketamine wears off, which it does quite rapidly, one is able to connect with the insight and emotions, and extinguish automatic negative thinking even though the state of consciousness returns to baseline. The effects of ketamine last because it forms new physical cellular pathways in the brain, which is called synaptogenesis. This is what inspired the name of the practice Genesis Ketamine Centers and is the mechanism underlying the process of neuroplasticity.
These connections are fragile, and it is easy to revert to the previous default state of negativity, so it is important to reinforce these new brain patterns. This is done by the treatment protocol that emphasizes that therapy sessions typically occur as a series of six, approximately one week apart and that booster infusions may be needed at even longer intervals. Many patients, depending on the condition, require more than six sessions to see lasting benefits. In addition, reinforcement of these new pathways comes from non-psychedelic practices such as meditation, mindfulness, conscious breath-work, physical exercise, nutrition, healthy sleep hygiene, gratitude, acceptance, and other practices to preserve the insights and more positive thought and emotional patterns gained from ketamine treatments.
We tend to associate mind-altering drug use, such as alcohol, cocaine, heroin, and others as causing negative health consequences. Habitual use of ketamine certainly will lead to irreversible damages, but in the appropriate setting, ketamine has shown promise to improve brain health.
Some mechanisms of ketamine that have been studied that support improved brain health include:
- The increase of the synthesis of brain-derived neurotrophic factor (BDNF), which is a protein that plays an important role in brain cell survival and growth, serves as a neurotransmitter modulator, and supports neuroplasticity.
- Ketamine administration leads to a surge in glutamate levels, which increases binding to the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor, also known as AMPA receptor, which is involved in learning and is believed to play a role in its antidepressant effect.
- In fact, the AMPA receptor activity has been shown to further increase activation of the mammalian target of rapamycin (mTOR) pathway, and subsequent stimulation of dendritic spine formation, the underlying proteins that form new connections in the brain.
- Studies have found increased transforming growth factor β1 (TGF-β1) expression, which is a protein that supports microglia, which work like the “janitorial” services of brain cells to “clean” and repair the nervous system.
Without diving too much deeper into these technical details, and to ground us back to the take home point, basic research demonstrates numerous reasons on why ketamine can protect and promote healing in the brain, in addition to insight learning. It is a powerful tool that can be used with many consciousness medicine practices to elevate health and a sense of wellness.
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