Don’t psychedelics just calm you down
Not necessarily - but the question these researchers, Praachi Tiwari et al., from Cornell University wanted to answer was how precisely - or what specifically happens in the brain to lower anxiety in some psychedelics?
OK and with what psychedelic?
They used a psychedelic called DOI that is a so-called serotonergic psychedelic. This similar to psilocybin, mescalin, and LSD targets the serotonin system in the brain.
Isn’t serotonin related to mood?
Yes, it is, but this neurotransmitter and modulator is involved in multiple processes.
And what did these researchers find?
Well, they found that DOI activates a specific type of neuron in a subregion of the hippocampus. The hippocampus is often associated with memory and navigation.
Activate - shouldn’t it be quieting neurons?
Yes and not. This activated so-called interneurons which connect different neurons and this resulted in quieting neighbouring neurons. This follows on from research that showed that anxiety in animals is also associated with communication between the ventral hippocampus and the amygdala our emotional and fear processing “centres”.
But what about the hallucinatory effects?
This seems to be independent of the hallucinatory effects. So there appear to be different mechanisms and in this case the anxiety appears to be reduced due to activation of neurons in the hippocampus.
And how will this help us?
Well, it gives us a clear understanding of what is happening in the brain with anxiety and potential other targets for this.
Other posts on psychedelics:
Reference
Praachi Tiwari, Pasha A. Davoudian, Darshana Kapri, et al.
Ventral hippocampal parvalbumin interneurons gate the acute anxiolytic action of the serotonergic psychedelic DOI.
Neuron, 2024
DOI: 10.1016/j.neuron.2024.08.016