Cannabis Increases Psychosis Risk Due to Brain Connectivity Shortfalls

Summary: Younger adults at risk of schizophrenia exhibit reduced neural concentration, a crucial brain connectivity deficit that cannabis use appears to compound, according to new research. Lower synaptic mass was found to be related to social withdrawal and depressive behaviors, both of which are currently ill addressed by medications. According to research, cannabis interferes with the mental development process known as neural pruning.

Using innovative head searching, the study marks the second real-time assessment of mental structural changes in high-risk individuals, offering insights into psychosis progression. These findings may help to develop treatments for treating schizophrenia ‘ cultural and functional imbalances. Second, we need to determine whether these mental changes may help us identify earlier illness developments.

Important Facts:

• Young adults who are at risk of schizophrenia may experience neural cutting disruptions as a result.
• Motivational and social withdrawal are related to lower neural density.
• This is the first real-time assessment of mental fundamental shifts in high-risk populations.

Origin: McGill University

Young people at risk of schizophrenia exhibit reduced mental communication, a gap that cannabis use appears to worsen, a new study has found. The discovery opens the door to psychotic therapies that focus on the symptoms that existing treatments ignore.

In the first-of-its-kind research, McGill University researchers detected a marked increases in neural density—the connections between neurons that enable mental communication—in individuals at risk of illness, compared to a good control group.

” No every cannabis user may develop schizophrenia, but for some, the risks are higher. Our analysis helps define why”, said&nbsp, Dr. Romina Mizrahi, top author of the study and professor in McGill’s Department of Psychiatry.

” Cannabis appears to disrupt the body’s normal process of refining and cutting neurons, which is essential for healthy mind development”.

Hope for innovative procedures

The team studied 49 participants between the ages of 16 and 30 using cutting-edge mind scanning technology, including those who have recently experienced schizophrenic symptoms and who are thought to be at higher risk.

The findings, published in&nbsp, JAMA Psychiatry, &nbsp, indicate that lower neural mass is linked to interpersonal withdrawal and lack of motivation, signs the experts say are difficult to treat.

” Current medications largely target hallucinations, but they do n’t address symptoms that make it difficult to manage social relationships, work, or school”, said first author Belen Blasco, a PhD student at McGill’s Integrated Program in Neuroscience.

We may eventually develop treatments that improve social function and the quality of life for those affected by our focus on synaptic density.

Cannabis is a well-known risk factor for schizophrenia, but this is the first time researchers have tracked structural changes in a high-risk population’s brains in real time.

Next research will be conducted by the team to determine whether these brain changes, which could lead to earlier intervention, can be predicted for psychosis development.

Funding: The study was conducted at the Douglas Mental Health University Institute and McGill University’s Montreal Neurological Institute-Hospital. The Canadian Institute of Health Research provided financial support for it.

About this news about psychosis and CUD.

Author: Keila DePape
Source: McGill University
Contact: Keila DePape – McGill University
Image: The image is credited to Neuroscience News

Original Research: Open access.
Romina Mizrahi and colleagues ‘” Clinical High Risk and Early Psychosis: Synaptic Density” JAMA Psychiatry

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Abstract

Clinical High Risk and Early Psychosis: Synaptic Density

Importance  

Synaptic dysfunction is involved in schizophrenia pathophysiology. However, whether in vivo synaptic density is reduced in early stages of psychosis, including its high-risk states, remains unclear.

Objective  

To investigate whether first-episode psychosis ( FEP ) and clinical high risk ( CHR ) result in a reduction in synaptic density and whether cannabis use has an impact on synaptic density, as well as how group-specific gray matter microstructure and psychotic symptoms affect the binding potential of SV2A binding proteins.

Design, Setting, and Participants&nbsp, &nbsp,

From July 2021 to October 2023, this cross-sectional study was carried out in a psychiatric hospital providing tertiary care. Patients with healthy controls and a clean urine drug test ( aside from cannabis ) were participants with antipsychotic-free or minimally exposed FEP or CHR.

Main Outcomes and Measures&nbsp, &nbsp,

Synaptic density was quantified with dynamic 90-minute]¹⁸F] SynVesT-1 positron emission tomography ( PET ) scans across prioritized brain regions of interest ( ROIs ) delineated in individual magnetic resonance images ( MRIs ). Urine drug tests revealed cannabis use. To calculate neurite density, diffusion-weighted MRI was used to assess gray matter microstructure.

Results  

A total of 49 participants were included, including 16 patients with FEP ( mean]SD] age, 26.1]4.6] years, 9 males and 7 females ), 17 patients at CHR ( mean]SD] age, 21.2]3.5] years, 8 males and 9 females ), and 16 healthy controls ( mean]SD] age, 23.4]3.6] years, 7 males and 9 females ).

Synaptic density was significantly different between groups ( F2, 273 = 4.02, &nbsp, P = .02, Cohen&nbsp, F = 0.17, ROI: &nbsp, F5, 273 = 360.18, &nbsp, P &lt, .01, Cohen&nbsp, F = 2.55 ) with a group × ROI interaction ( F10, 273 = 2.67, &nbsp, P &lt, .01, Cohen&nbsp, F = 0.32 ). Synaptic density was lower in cannabis users ( F1, 272 = 5.31, &nbsp, P = .02, Cohen&nbsp, F = 0.14 ).

Lower synaptic density across groups was associated with more negative symptoms ( Positive and Negative Syndrome Scale negative scores: &nbsp, F1, 81 = 4.31, &nbsp, P = .04, Cohen&nbsp, F = 0.23, Scale of Psychosis-Risk Symptoms negative scores: &nbsp, F1, 90 = 4.12, &nbsp, P = .04, Cohen&nbsp, F = 0.21 ). SV2A binding potential was significantly associated with neurite density index ( F1, 138 = 6.76, &nbsp, P = .01, Cohen&nbsp, F = 0.22 ).

Conclusions and Relevance&nbsp, &nbsp,

In this study, synaptic density reductions were found to be present in the early stages of psychosis, its risk states, and its negative symptoms. Further investigation is necessary to understand the effects of SV2A on CHR and psychosis negative symptoms. The longitudinal impact of cannabis use on the synaptic density in CHR should be studied in future studies.