It’s well established that cannabis use can trigger psychosis in young people susceptible to schizophrenia. Until January 2025,however, the origins of this trigger mechanism remained a mystery. With the publication of a new study by members of Canada’s McGill University Department of Psychiatry in the journal JAMA Psychiatry, this mechanism has become clearer — suggesting, among other things, new avenues for the development of medications to treat those with cannabis psychosis and related disorders.
The researchers examined the binding potential of a protein called SVA2, which is closely related to the density of synapses (signal connections) in the human brain. Questions pursued were whether synaptic density is altered among those with first-episode psychosis (FEP) and clinical high risk (CHR) for psychosis, and whether cannabis use affects synaptic density.
They found, in their study of 49 young adults in their20s, that synaptic density was reduced in CHR patients and in those who had suffered FEP, as well as in cannabis users. It is also “associated with negative symptoms” in all three groups. The researchers suggested that SVA2 can be used as a molecular target in new drugs to help treat psychosis caused by cannabis use, and to better understand the reduced synaptic density in all of the above patients. They also advised that larger, long-term studies be conducted to fully investigate cannabis’s effect on synaptic density.
For more information, click here, or click here to read the JAMA publication.