Psychedelics stimulate cells in the hippocampus and thus reduce anxiety

The results show that the psychedelic DOI (2,5-dimethoxy-4-iodoamphetamine) reduced anxiety in mice and rats while activating the ventral hippocampus and the so-called fast-firing interneurons there.

“It was not known which brain areas and cell types are involved when psychedelics suppress anxiety,” said Alex Kwan, associate professor of biomedical engineering at Cornell University and senior author of the study, published today in the journal Neuron“The idea is that if we know the underlying neurobiology, we can develop a better drug that targets these signaling pathways.”

“The work provides an understanding of the cellular trigger of psychedelic-induced anxiety relief,” said Vidita Vaidya, professor of biological sciences at the Tata Institute of Fundamental Research in Mumbai and corresponding author of the paper.

The pathway in the ventral hippocampus – a brain structure involved in social memory, emotion and affect – does not appear to cause the hallucinations that are a hallmark of DOI. That suggests that some of the therapeutic effects of psychedelics – including relief of PTSD, depression and anxiety – may be limited to certain brain circuits, Vaidya said.

“This opens up the possibility of developing psychedelic-inspired drugs that target anxiety without inducing powerful hallucinations,” she added.

The study builds on previous research that found abnormal hyperactivity in the ventral hippocampus of anxious animals, specifically neurons that communicate with the amygdala, the main processing center for emotions.

“There is evidence that these cells are active in anxiety states. Perhaps the drug works by silencing some of these cells,” Kwan said.