Grant: Doctoral: Vanier Canada Graduate Scholarships

Adolescent e-cigarette use has seen a dramatic increase in recent years with past year nicotine vaping among Ontario grade 7-12 students growing from 10.7% to 22.7% between 2017 and 2019. JUUL is currently the most popular e-cigarette, with 78% of the Canadian e-cigarette market share. It is also unique in its higher nicotine concentrations through the use of nicotine salts which allows for smoother inhalation and higher absorption, all potentially contributing to its high uptake among adolescents. Currently, the behavioural and neural mechanisms underlying the high uptake of JUUL e-cigarettes in youth, as well as the long-term causal consequences of this use, are not known. Therefore, there is a critical need for establishing the short- and long-term effects of nicotine vapour on the adolescent brain. There is a substantial body of literature that suggests that adolescents are especially vulnerable to the addictive effects of nicotine. There are also longitudinal studies that associate adolescent e-cigarette use with a greater risk for future initiation of cigarette smoking. This may suggest that adolescent nicotine vapour exposure produces behavioural and neural effects that are distinct from those in adults, and may impact the neurodevelopmental trajectories in adolescents that lead to future addiction vulnerability. No studies to date have studied the causal impacts of adolescent nicotine vapour exposure on future nicotine addiction liability and related neural circuitry. The proposed research intends to contribute to our understanding of the vulnerability of the adolescent brain to the rewarding effects of e-cigarette vapour. This research has the potential to have a high impact through improving our knowledge of nicotine's short- and long-term effects on brain circuitry, apprising the public of the potential neurodevelopmental ramifications of adolescent nicotine exposure, and through future research aimed at preventing or reversing these effects.