Nicotine use during late adolescence and young adulthood is associated with changes in hippocampal volume and memory performance

BackgroundWith the advent of electronic nicotine delivery systems, the use of nicotine and tobacco products (NTPs) among adolescents and young adults remains high in the US. Use of e-cigarettes additionally elevates the risk of problematic use of other substances like cannabis, which is often co-used with NTPs. However, their effects on brain health, particularly the hippocampus, and cognition during this neurodevelopmental period are poorly understood.MethodsHealthy late adolescents/young adults (N = 223) ages 16-22 completed a structural MRI to examine right and left hippocampal volumes. Memory was assessed with the NIH Toolbox Picture Sequence Memory Test (PSMT) and Rey Auditory Verbal Learning Test (RAVLT). Cumulative 6-month NTP and cannabis episodes were assessed and modeled continuously on hippocampal volumes. Participants were then grouped based on 6-month NTP use to examine relationships with the hippocampus and memory: current users (CU) endorsed weekly or greater use; light/abstinent users (LU) endorsed less than weekly; and never users (NU).ResultsNTP use predicted larger hippocampal volumes bilaterally while cannabis use had no impact nor interacted with NTP use. For memory, larger left hippocampal volumes were positively associated with PSMT performance, RAVLT total learning, short delay and long delay recall for the NU group. In contrast, there was a negative relationship between hippocampal volumes and performances for LU and CU groups. No differences were detected between NTP-using groups.ConclusionThese results suggest that the hippocampus is sensitive to NTP exposure during late adolescence/young adulthood and may alter typical hippocampal morphometry in addition to brain-behavior relationships underlying learning and memory processes

Efficacy of Mentalization-Based Group Therapy for adolescents:A pilot randomised controlled trail

oai:ojs.pkp.sfu.ca:article/2647Background: Suicide is the leading cause of death in adolescents. Furthermore, up to one quarter of adolescents who self-harm will repeat self-harm within one year, highlighting the need for evidence-based prevention and treatment services. Mentalization Based Therapy (MBT) has yielded promising outcomes for individuals who self-harm, however to date only one study has examined MBT in adolescents, wherein the treatment protocol consisted of individual and family therapy. Currently, there has been no development or examination of MBT-A in a group format for adolescents. Methods/Design: The present study is a randomised controlled single blind feasibility trial that aims to (1) adapt the original explicit MBT introductory group manual for an adolescent population (MBT-Ai) and to (2) assess the feasibility of MBT-Ai through examination of consent rates, attendance, attrition and self-harm. Participants are adolescents presenting to Child and Adolescent Mental Health Services (CAMHS) with self-harming behaviors within the last 6 months. Young people will be randomised to a 12-week MBT-Ai group plus treatment as usual (TAU) or TAU alone. Participants will be assessed at baseline and at 12-, 24- and 36-weeks post-baseline. Discussion: This paper describes the development of a treatment manual and the protocol of a randomised controlled feasibility trial of MBT-Ai aimed at treating adolescents who self-harm. Further investigation of a full-scale trial will be necessary to instill benefits if pilot results suggest efficacy. Trial registration: NCT0277169

The Combined Effects of Nicotine and Cannabis on Cortical Thickness Estimates in Adolescents and Emerging Adults

Early life substance use, including cannabis and nicotine, may result in deleterious effects on the maturation of brain tissue and gray matter cortical development. The current study employed linear regression models to investigate the main and interactive effects of past-year nicotine and cannabis use on gray matter cortical thickness estimates in 11 bilateral independent frontal cortical regions in 223 16-22-year-olds. As the frontal cortex develops throughout late adolescence and young adulthood, this period becomes crucial for studying the impact of substance use on brain structure. The distinct effects of nicotine and cannabis use status on cortical thickness were found bilaterally, as cannabis and nicotine users both had thinner cortices than non-users. Interactions between nicotine and cannabis were also observed, in which cannabis use was associated with thicker cortices for those with a history of nicotine and tobacco product (NTP) use in three left frontal regions. This study sheds light on the intricate relationship between substance use and brain structure, suggesting a potential modulation of cannabis' impact on cortical thickness by nicotine exposure, and emphasizing the need for further longitudinal research to characterize these interactions and their implications for brain health and development