When Biology Helps Us Change
What Incretin-Based Medicines and Psychedelics May Have in Common
Over the past few years, two very different areas of medicine have been receiving growing attention.
One involves psychedelic therapies being studied at research institutions such as Johns Hopkins Center for Psychedelic and Consciousness Research, Stanford Psychedelic Science Group, and Imperial College Center for Psychedelic Research. Scientists are exploring how compounds like psilocybin may help people with depression, trauma, addiction, and other conditions.
The other involves a newer class of metabolic medications often referred to as incretin-based therapies, including drugs such as semaglutide and tirzepatide. These medicines were originally developed for diabetes but have become widely known for their effects on appetite and weight regulation.
At first glance, these developments appear unrelated. One belongs to the world of consciousness research and psychotherapy. The other emerged from endocrinology and metabolic medicine. Yet researchers are beginning to notice something interesting. Both approaches appear to influence some of the same underlying systems involved in habit formation, reward processing, and behavioral change.
Understanding that overlap may illuminate something deeper about how people change.
What Incretin-Based Medicines Actually Do
Many of these medications work by mimicking hormones known as incretins, which the body naturally releases after eating. These hormones help regulate blood sugar, appetite, and digestion.
Some drugs, such as semaglutide (sold under brand names like Ozempic and Wegovy), act primarily by activating GLP-1 receptors.
Others, such as tirzepatide (sold as Mounjaro and Zepbound), activate two incretin pathways—GLP-1 and another hormone called GIP.
Despite these differences, the medicines are often discussed together because they produce similar metabolic effects. Most people know these medications for their effects on appetite. They slow gastric emptying, increase feelings of fullness, and reduce hunger signals. But researchers have also discovered that incretin signaling interacts with areas of the brain involved in motivation and reward, including the ventral tegmental area and nucleus accumbens. These regions are central to dopamine signaling and reinforcement learning.
Because of this, many people taking these medications report not only changes in appetite but also reductions in other reward-driven behaviors. Some describe decreased interest in alcohol, fewer cravings for highly processed foods, or less impulsive reward seeking. Researchers are now studying whether incretin-based medicines may have potential roles in treating addictive behaviors.
How Psychedelics Affect Behavior
Classic psychedelics such as LSD and DMT appear to influence behavior through a different biological pathway. These compounds activate serotonin receptors in the brain, particularly the 5-HT2A receptor, which is associated with perception, cognition, and emotional processing.
Research suggests that psychedelic compounds can temporarily increase neuroplasticity, allowing the brain to form new patterns of connection and communication. Brain imaging studies also show changes in the default mode network, a system associated with self-referential thinking and habitual mental narratives. During psychedelic experiences, activity in this network often decreases while communication between normally separate brain regions increases. Many participants describe this state as allowing them to step outside familiar patterns of thinking and see their lives from a wider perspective.
Two Different Mechanisms, Similar Outcomes
Although incretin-based medicines and psychedelics act on very different biological systems, their effects sometimes converge in an interesting way. Both appear capable of interrupting automatic behavioral loops.
Incretin-based medicines appear to work by reducing the intensity of reward signals. People often report fewer cravings and less impulsive motivation toward certain behaviors.
Psychedelics appear to work by changing the way the brain interprets those signals. They may allow people to axamine habits and patterns from a new vantage point.
In simplified terms:
Incretin medicines may quiet the signal.
Psychedelics may change the perspective on the signal.
In both cases, the result can be a moment where previously rigid patterns become more flexible.
The Gut–Brain Connection
Another interesting overlap involves the gut–brain axis, the network of communication between the digestive system and the brain. Incretin hormones originate partly in the digestive system and communicate with the brain through hormonal pathways and the vagus nerve. Psychedelic experiences, particularly those involving compounds such as DMT found in ayahuasca, often involve strong physical sensations in the body. Many participants report that emotional processing during these experiences is accompanied by visceral sensations in the gut or chest.
Scientists increasingly recognize that emotional regulation, metabolism, and cognition are deeply interconnected through these biological systems. What we experience psychologically is often closely linked to signals moving through the body.
A Window for Change
One concept that appears repeatedly in psychedelic research is the idea of a temporary window of increased plasticity. For a period after a psychedelic experience, the brain may be more flexible and receptive to new perspectives and behaviors. Researchers are beginning to ask whether incretin-based medicines may create a different kind of window by reducing the biological signals that reinforce habitual reward seeking.
In both cases, the biology shifts slightly in a direction that may make behavioral change more possible. The change itself, however, still depends on what a person chooses to do during that window.
Psychedelics and Addiction: An Emerging Area of Research
One area where this overlap may become particularly important is addiction. Early research into psychedelic therapies has shown promising results for conditions such as smoking cessation and alcohol use disorder. Some studies have reported unusually high rates of long-term abstinence following carefully structured psychedelic therapy sessions.
At the same time, incretin-based medications are now being studied for their potential ability to reduce alcohol consumption and other reward-driven behaviors. Although the mechanisms differ, both approaches appear to influence the biological systems that reinforce habit loops. Researchers are only beginning to explore how these insights might complement one another.
A Broader Perspective on Change
What makes this convergence interesting is not that these two approaches are identical. They are not. They come from entirely different traditions of medicine and science. Yet both seem to illuminate something important about human behavior.
Habits are rarely changed through willpower alone. They are shaped by complex interactions between biology, environment, and meaning.
Sometimes meaningful change begins when the systems that reinforce those habits become temporarily more flexible. Whether that flexibility comes from shifts in metabolism, changes in neural signaling, or profound experiences that alter perspective, the same question eventually emerges:
What will someone do with that moment of openness?
Selected References
Carhart-Harris, R. L., & Friston, K. J. (2019). REBUS and the Anarchic Brain: Toward a Unified Model of the Brain Action of Psychedelics. Pharmacological Reviews.
Johnson, M. W., Garcia-Romeu, A., & Griffiths, R. R. (2017). Long-term follow-up of psilocybin-facilitated smoking cessation. Journal of Psychopharmacology.
Timmermann, C., et al. (2019). Neural correlates of the DMT experience assessed with multivariate EEG. Scientific Reports.
Secher, A., et al. (2014). Central GLP-1 receptor signaling and reward pathways. Diabetes.
Müller, T. D., et al. (2019). The role of GLP-1 in appetite and reward signaling. Cell Metabolism.
