Dr. Conrod invited to comment on a study published in the American Journal of Psychiatry on long term effects of cannabis on brain health. Comment on "Long-Term Cannabis Use and Cognitive Reserves and Hippocampal Volume in Midlife."

A unique sample of 86 youths was recruited from a population-based sample of over 3800 adolescents who had been followed from 13 to 17 years of age. Three groups were identified based on validated developmental trajectories: a control trajectory with low and decreasing Psychotic-like experiences (PLEs), and two atypical trajectories with moderate to elevated baseline PLEs that subsequently decreased or increased. All had functional magnetic resonance imaging data collected during a facial emotion processing task. Functional activation and connectivity data were analyzed for different contrasts. The increasing trajectory reported more positive symptoms and exhibited dysconnectivity in areas that influence emotion salience and face perception. Whereas, the decreasing trajectory reported more negative symptoms had impairments in visual information integration areas. These group-specific features might account for the differential symptom expression. 

Fifteen to 25-year-olds are the age group most likely to misuse prescription drugs. Few studies have tested theory-driven models of adolescent risk for prescription drug misuse. Moreover, rarely are distinct pathways to different forms of prescription drug misuse considered.

The major aim of our systematic review and meta-analyses was to highlight the relationship between cognitive biases and psychotic-like experiences (PLEs) when both are assessed by self-reports measures.

Major neurocognitive changes occur during adolescence, making this phase one of the most critical developmental periods of life. Furthermore, this phase in life is also the time in which youth substance use begins. Several studies have demonstrated the differential associations of alcohol and cannabis use concerning the neurocognitive functioning of both males and females.

A mainstay treatment for opioid addiction in North America is methadone maintenance therapy (MMT) - a form of opiate agonist therapy (OAT).

Most psychopathological disorders develop in adolescence. The biological basis for this development is poorly understood. To enhance diagnostic characterization and develop improved targeted interventions, it is critical to identify behavioural symptom groups that share neural substrates.

This study examined the secondary mental health outcomes of two contrasting alcohol prevention approaches, whereby one intervention targets common underlying personality risk for alcohol use and mental health problems (Preventure) and the other targets alcohol- and drug-related behaviours and cognitions (Climate Schools).

The cortical‐cerebellar circuit is vulnerable to heavy drinking (HD) in adults. We hypothesized early microstructural modifications of the pons/midbrain region, containing core structures of the reward system, in HD adolescents.

Increases in screen time have been found to be associated with increases in depressive symptoms. However, longitudinal studies are lacking.

Studying the neural consequences of tobacco smoking during adolescence, including those associated with early light use, may help expose the mechanisms that underlie the transition from initial use to nicotine dependence in adulthood.

To examine the secondary effects of a personality-targeted intervention on bullying and harms among adolescent victims and bullies.

To characterize the structural and functional neurobiology of a large group of adolescents exhibiting a behaviorally and emotionally dysregulated phenotype.

Impulse control is becoming a critical survival skill for the twenty-first century. Impulsivity is implicated in virtually all externalizing behaviours and disorders, and figures prominently in the aetiology and long-term sequelae of substance use disorders (SUDs).

There are indications that screen time is associated with symptoms of anxiety in adolescents, but from a longitudinal perspective, the magnitude, specificity, and temporal precedence in this association are relatively under-explored. To address this gap, over the course of 4 years, we annually surveyed adolescents assessing their usage of various types of screen time per day and symptoms of anxiety.