Association between Cannabis Use and Psychotic Experiences: Investigating Potential Psychological and Cognitive Mechanisms - CANTRIPS Study
Association between Cannabis Use and Psychotic Experiences: Investigating Potential Psychological and Cognitive Mechanisms (CANTRIPS) is a longitudinal study that investigates the relationship between cannabis use and psychotic-like experiences (PLEs), and the possible mechanisms (eg. Memory, Perception & Predictive Processing etc.) that may underlie this association.
We are now open for a new round of participant recruitment in the UK.
Aims
We would like to explore the following hypotheses:
- Individuals that consume cannabis and perform worse on the cognitive tasks at baseline will predict a larger extent of increase in frequency and associated distress of PLEs.
- For participants that do not meet the criteria of ultra-high risk (UHR) of developing psychosis at baseline, cannabis use and a worse performance on the cognitive tasks at baseline will predict a higher chance of transiting to UHR group at follow-up.
- For participants that meet the criteria of UHR of developing psychosis at baseline, cannabis use and a worse performance on the cognitive tasks at baseline will predict a higher chance of transiting to psychosis at follow-up.
- The association between cannabis use and psychotic symptoms can be explained by cognitive mechanisms such as deficits in memory, perception and predictive processing etc., which will present as a mediating factors.
Methods
Participants
- Aged between 16-35
- Based in the UK
- English Language Fluency
- Cannabis Use or Not
Online Survey (Gorilla Platform)
- Demographic Information
- Questionnaire on Psychotic-like Experiences (CAPE-15)
- Questionnaire on Cannabis Use
- Two Cognitive Tasks (SPACE Task and Prediction Task)
- SPACE Task: How people make decisions based on different weighting of priors and new information.
- Prediction Task: How people make decisions by integrating two sources of information in congruent and contradictory conditions.
Online Interview (Microsoft Teams)
- Two Cognitive Tasks (Memory Task and Perception Task)
- Demographic Information
- Cannabis Use Patterns (CEQ Questionnaire)
- Subclinical Psychotic Symptoms (CAARMS Interview)
Participants are being recruited through poster presentation across University of London Institutions, flyer distribution on King's College London campuses and Central London, and Advertisement on social media (e.g. Instagram, Facebook, X, etc.)
Participants who take part in the online survey and meet the criteria for the online interview will be invited through Email and WhatsApp.
Impact
Studies have shown that there is a correlation between regular cannabis use and increased risk for psychosis, but the directionality of this association remains unclear since most of the studies that have been done are cross-sectional studies.
Through this longitudinal study, we are be able to figure out the causality and make possible predictions of the risk of developing psychotic symptoms, transiting to UHR and psychosis based on cannabis use pattern and task performance.
Principal Investigator
Professor of Translational Neuroscience and Psychiatry