Longitudinal fMRI reveals altered developmental trajectories of functional network organisation associated with adolescent cannabis use
Elizabeth J Davies, Natalie Ertl, Tom P. Freeman, Anya Borissova, Rachel Lees Thorne, Shelan Ofori, Kat Petrilli, Clare Mokrysz, Helen Valerie Curran, Will Lawn, Matthew B. Wall
Study at a glance
AI-extracted from the abstract| Characteristics | Observational longitudinal study |
|---|---|
| Sample size | 66 |
| Population | Adolescents aged 16-17 years and adults aged 26-29 years, including regular cannabis users and age-matched cannabis-naive controls |
| Duration | Two time points one year apart |
| Topics | Cannabis |
| Key findings | Age-by-cannabis-use-group interactions were found in one-year changes in salience and default mode network connectivity, including divergent changes in anticorrelations with medial prefrontal, thalamic, cerebellar and juxtapositional regions, with directionality differing by network and region. Cannabis users also showed decreased positive executive control connectivity and reduced anticorrelation in associative striatal connectivity. The authors suggest these patterns may reflect age-related differences in neurobiological sensitivity to cannabis exposure. |
Abstract
Adolescence is a critical period of brain development during which the endocannabinoid system continues to mature. These developmental changes may contribute to age-related differences in the association between cannabis use and large-scale functional network organisation, yet this association remains incompletely characterised. We hypothesised that regular cannabis use would be associated with differential one-year changes in resting-state functional connectivity between adolescents and adults. Resting-state fMRI data at two time points, one year apart, were analysed from 66 participants (31 aged 16-17 years; 35 aged 26-29 years) including 29 with regular cannabis use and 37 age-matched cannabis-naive controls. Seed-to-voxel analyses examined longitudinal changes in functional connectivity across age and cannabis-use groups. Year change, age by user-group interactions were identified in salience and default mode network connectivity, including divergent changes in anticorrelations with medial prefrontal, thalamic, cerebellar and juxtapositional regions. Directionality of effects differed by network and region. Additional main effects of user group were observed for executive control and associative striatal connectivity, with the cannabis-use group showing decreased positive connectivity and reduced anticorrelation, respectively. Changes in functional connectivity were developmentally dissociable and predominantly observed in regions contributing to attentional and transmodal processing. These findings suggest that cannabis may be associated with alterations in the maturational refinement of higher-order neural systems, potentially reflecting age-related differences in neurobiological sensitivity to cannabis exposure. Considering developmental stage may therefore be important for characterising cannabis-related neurobiological differences and may have implications for understanding age-dependent vulnerability to cannabis-related psychiatric outcomes.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |