Serotonergic Psychedelics in Neural Plasticity
Summary & key facts
This review explains that classical serotonergic psychedelics — drugs like psilocybin, DMT (in ayahuasca), LSD, and ibogaine — can change brain cells and connections in lab and animal studies. These drugs have been shown to help neurons grow new branches and form more synapses, which are the contact points where brain cells talk to each other. The review says these effects might help explain why scientists are interested in using psychedelics to treat conditions such as depression, addiction, and anxiety, but it also points out that the biology is complex, effects depend on dose and sex, and some drugs can be toxic at high doses, so more research is needed.
- Psychedelic drugs can boost neuroplasticity, which means they help neurons grow new branches and make more synapses — the tiny contact points where brain cells communicate.
- In lab-grown rat brain cells, DMT increased the number, length, and complexity of neuron branches and raised the number of dendritic spines, which are markers of new synapses.
- A single large dose of DMT increased synapse number and the strength and frequency of excitatory signals in the prefrontal cortex of adult rats, showing structural and functional change together.
- A low, repeated dose of DMT produced the opposite effect in one study: it reduced spine density in female rats but not in males, which shows effects can depend on dose and sex.
- Noribogaine, the main breakdown product of ibogaine, increased branching of neurons in cultured cells, but high doses of ibogaine itself can damage certain brain cells in animals, revealing safety concerns.
- Many classical psychedelics act at the serotonin 2A receptor (called 5-HT2A), and blocking that receptor can stop some psychedelic-induced changes and the subjective hallucinatory effects in humans and animals.
- Some compounds that encourage plasticity lack strong hallucinatory effects, which suggests it might be possible to get brain-changing benefits without intense psychedelic experiences.
- The review links these neuroplastic changes to why researchers are exploring psychedelics for psychiatric problems like depression, addiction, anxiety, and PTSD, but it stresses that the evidence is mostly from cells and animals and that hu
Abstract
Psychedelics, compounds that can induce dramatic changes in conscious experience, have been used by humans for centuries. Recent studies have shown that certain psychedelics can induce neural plasticity by promoting neurite growth and synapse formation. In this review, we focus on the role of classical serotonergic psychedelics in neural plasticity and discuss its implication for their therapeutic potentials.