Here, we identify a shared spatial pattern of cortical thickness (CT) in normative development and several psychiatric and neurological disorders. Principal component analysis (PCA) was applied to CT of 68 regions in the Desikan-Killiany atlas derived from three large-scale datasets comprising a total of 41,075 neurotypical participants. PCA produced a spatially broad first principal component (PC1) that was reproducible across datasets.

Increasing evidence implicates cannabis consumption as a key risk factor in the development of psychosis, but the mechanisms underpinning this relationship remain understudied. This study proposes to determine whether sleep disruption acts as a mediator of the cannabis-to-psychosis relationship.

Self-disturbances constitute a hallmark of psychosis, but it remains unclear whether these alterations are present in at-risk populations, and therefore their role in the development of psychosis has yet to be confirmed. The present study addressed this question by measuring neural correlates of self-other processing in youth belonging to three developmental trajectories of psychotic experiences. During a self-other processing task, youth who showed an increasing trajectory displayed hypoactivation of the dorsomedial prefrontal cortex and hypoconnectivity with the cerebellum. By contrast, youth who showed a decreasing trajectory displayed decreased activation of the superior temporal gyrus, the inferior frontal gyrus, and the middle occipital gyrus. These findings suggest that the increasing trajectory is associated with alterations that might erode distinctions between self and other, influencing the emergence of symptoms such as hallucinations. The decreasing trajectory, in comparison, was associated with hypoactivations in areas influencing attention and basic information processing more generally. These alterations might affect the trajectories’ susceptibilities to positive vs. negative symptoms, respectively.

This study characterizes service provider needs, gaps, and problem areas in the provision of opioid-related services for young people ages 15 to 25 across Canada.

There is a lack of knowledge regarding how diverse young people (ages 15–25) experience opioid use, connect to opioid-related services, and navigate opioid use disorder. Knowledge is urgently needed to inform the development of prevention and treatment for youth. This article outlines a protocol for a pan-Canadian youth engagement summit and discusses the successes and challenges experienced and outlines suggestions for future engagement initiatives of this kind.

With the opioid overdose and health crisis rapidly growing and evolving in North America, this special issue provides an opportunity to present a series of studies involving investigators in this field from across the country. Our working group involves diverse expertise in disciplines including critical public health, sociology, psychiatry, psychology, and anthropology.

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."

Youth and young adults have been significantly impacted by the opioid overdose and health crisis in North America. Our review of key international reports indicates there are few youth-focused interventions and treatments for opioid use. Our scoping review sought to identify, characterize, and qualitatively evaluate the youth-specific clinical and pre-clinical interventions for opioid use among youth.

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.

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.

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).