Adolescent brain development and the risk for alcohol and other drug problems

Impaired Control (Both Attempts to Control Drinking and Failed Control) as Prospective Predictors of Negative Outcomes Among Young Adults Who Drink Heavily

OBJECTIVE

Impaired control over alcohol is a hallmark of addiction relevant to young adults, but additional prospective findings are needed, particularly in samples reporting heavy drinking. Further, we lack understanding of how attempts and failed efforts to control drinking relate to each other in predicting outcomes. We hypothesized that attempted and failed control would prospectively predict outcomes, with endorsement of both being especially problematic.

METHOD

We used data from young adults reporting heavy drinking who enrolled in laboratory alcohol self-administration studies (n = 109). Mixed-effects models were used to predict drinks per drinking day, heavy drinking, and negative consequences across baseline and 6- and 12-month follow-ups. Interactions by time and between attempted and failed control were tested.

RESULTS

Higher failed control was associated with steeper declines in consequences and heavy drinking over time compared with lower failed control. However, higher attempted or failed control was still associated with more consequences and alcohol use than lower impaired control at multiple time points. A significant interaction indicated that the combination of higher attempted and failed control was associated with the most drinks per drinking day. There was also a significant Attempted × Failed Control interaction for heavy drinking.

CONCLUSIONS

These findings provide further evidence supporting impaired control over alcohol use as a risk factor among young adults. Those reporting both higher attempted and failed control drank the most per day. Either attempted or failed control was associated with negative consequences. Those reporting both higher attempted and failed control may be in greatest need of intensive intervention.

Adolescent alcohol exposure persistently alters orbitofrontal cortical encoding of Pavlovian conditional stimulus components in female rats

Exposure to alcohol during adolescence impacts cortical and limbic brain regions undergoing maturation. In rodent models, long-term effects on behavior and neurophysiology have been described after adolescent intermittent ethanol (AIE), especially in males. We hypothesized that AIE in female rats increases conditional approach to a reward-predictive cue and corresponding neuronal activity in the orbitofrontal cortex (OFC) and nucleus accumbens (NAc). We evaluated behavior and neuronal firing after AIE (5 g/kg intragastric) or water (CON) in adult female rats. Both AIE and CON groups expressed a ST phenotype, and AIE marginally increased sign-tracking (ST) and decreased goal-tracking (GT) metrics. NAc neurons exhibited phasic firing patterns to the conditional stimulus (CS), with no differences between groups. In contrast, neuronal firing in the OFC of AIE animals was greater at CS onset and offset than in CON animals. During reward omission, OFC responses to CS offset normalized to CON levels, but enhanced OFC firing to CS onset persisted in AIE. We suggest that the enhanced OFC neural activity observed in AIE rats to the CS could contribute to behavioral inflexibility. Ultimately, AIE persistently impacts the neurocircuitry of reward-motivated behavior in female rats.

Epigenetic regulation of microglia and neurons by proinflammatory signaling following adolescent intermittent ethanol (AIE) exposure and in human AUD

Adolescent alcohol drinking is linked to high rates of adult alcohol problems and alcohol use disorder (AUD). The Neurobiology of Alcohol Drinking in Adulthood (NADIA) consortium adolescent intermittent ethanol (AIE) models adolescent binge drinking, followed by abstinent maturation to adulthood to determine the persistent AIE changes in neurobiology and behavior. AIE increases adult alcohol drinking and preference, increases anxiety and reward seeking, and disrupts sleep and cognition, all risks for AUD. In addition, AIE induces changes in neuroimmune gene expression in neurons and glia that alter neurocircuitry and behavior. HMGB1 is a unique neuroimmune signal released from neurons and glia by ethanol that activates multiple proinflammatory receptors, including Toll-like receptors (TLRs), that spread proinflammatory gene induction. HMGB1 expression is increased by AIE in rat brain and in post-mortem human AUD brain, where it correlates with lifetime alcohol consumption. HMGB1 activation of TLR increase TLR expression. Human AUD brain and rat brain following AIE show increases in multiple TLRs. Brain regional differences in neurotransmitters and cell types impact ethanol responses and neuroimmune gene induction. Microglia are monocyte-like cells that provide trophic and synaptic functions, that ethanol proinflammatory signals sensitize or "prime" during repeated drinking cycles, impacting neurocircuitry. Neurocircuits are differently impacted dependent upon neuronal-glial signaling. Acetylcholine is an anti-inflammatory neurotransmitter. AIE increases HMGB1-TLR4 signaling in forebrain, reducing cholinergic neurons by silencing multiple cholinergic defining genes through upregulation of RE-1 silencing factor (REST), a transcription inhibitor known to regulate neuronal differentiation. HMGB1 REST induction reduces cholinergic neurons in basal forebrain and cholinergic innervation of hippocampus. Adult brain hippocampal neurogenesis is regulated by a neurogenic niche formed from multiple cells. In vivo AIE and in vitro studies find ethanol increases HMGB1-TLR4 signaling and other proinflammatory signaling as well as reducing trophic factors, NGF, and BDNF, coincident with loss of the cholinergic synapse marker vChAT. These changes in gene expression-transcriptomes result in reduced adult neurogenesis. Excitingly, HMGB1 antagonists, anti-inflammatories, and epigenetic modifiers like histone deacetylase inhibitors restore trophic the neurogenesis. These findings suggest anti-inflammatory and epigenetic drugs should be considered for AUD therapy and may provide long-lasting reversal of psychopathology.

The influence of socioenvironmental risk factors on risk-taking behaviors among Bahamian adolescents: a structural equation modeling analysis

Background

Adolescents' risk-taking behaviors can have profound impacts on their future health. Few studies have established a relationship between multiple social environmental factors and adolescent risk behaviors. We used structural equation modeling to examine the role of parental monitoring and environmental risks on adolescents' behavioral intentions and risk behaviors.

Methods

Data were collected through the baseline survey of a national implementation project among 2205 Grade 6 students in 24 government schools in The Bahamas in 2019. Structural equation modeling examined relations among parental monitoring, environmental risk factors, behavioral intentions, and risk behaviors.

Results

Students had engaged in various delinquent, substance use, and sexual risks. In the structural equation model, parental monitoring demonstrated direct negative (protective) effects on behavioral intentions and risk behaviors, whereas environmental risk factors had a direct positive effect on adolescent behavioral intentions and risk behaviors. The model had an R2 value of 0.57 for adolescent risk behaviors.

Conclusion

Parental monitoring and environmental risk factors had strong influences on risk-taking behaviors of early adolescents. Future adolescent health behavior interventions should consider offering additional prevention resources to early adolescents who are exposed to multiple environmental risk factors.

Brain structural covariance network features are robust markers of early heavy alcohol use

BACKGROUND AND AIMS

Recently, we demonstrated that a distinct pattern of structural covariance networks (SCN) from magnetic resonance imaging (MRI)-derived measurements of brain cortical thickness characterized young adults with alcohol use disorder (AUD) and predicted current and future problematic drinking in adolescents relative to controls. Here, we establish the robustness and value of SCN for identifying heavy alcohol users in three additional independent studies.

DESIGN AND SETTING

Cross-sectional and longitudinal studies using data from the Pediatric Imaging, Neurocognition and Genetics (PING) study (n = 400, age range = 14-22 years), the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) (n = 272, age range = 17-22 years) and the Human Connectome Project (HCP) (n = 375, age range = 22-37 years).

CASES

Cases were defined based on heavy alcohol use patterns or former alcohol use disorder (AUD) diagnoses: 50, 68 and 61 cases were identified. Controls had none or low alcohol use or absence of AUD: 350, 204 and 314 controls were selected.

MEASUREMENTS

Graph theory metrics of segregation and integration were used to summarize SCN.

FINDINGS

Mirroring our prior findings, and across the three data sets, cases had a lower clustering coefficient [area under the curve (AUC) = -0.029, P = 0.002], lower modularity (AUC = -0.14, P = 0.004), lower average shortest path length (AUC = -0.078, P = 0.017) and higher global efficiency (AUC = 0.007, P = 0.010). Local efficiency differences were marginal (AUC = -0.017, P = 0.052). That is, cases exhibited lower network segregation and higher integration, suggesting that adjacent nodes (i.e. brain regions) were less similar in thickness whereas spatially distant nodes were more similar.

CONCLUSION

Structural covariance network (SCN) differences in the brain appear to constitute an early marker of heavy alcohol use in three new data sets and, more generally, demonstrate the utility of SCN-derived metrics to detect brain-related psychopathology.

Abuse-like toluene exposure during early adolescence alters subsequent ethanol and cocaine behavioral effects and brain monoamines in male mice

Currently, there is a gap in understanding the neurobiological impact early adolescent toluene exposure has on subsequent actions of other drugs. Adolescent (PND 28-32) male Swiss-Webster mice (N = 210) were exposed to 0, 2000, or 4000 ppm of toluene vapor for 30 min/day for 5 days. Immediately following the last toluene exposure (PND 32; n = 15) or after a short delay (PND 35; n = 15), a subset of subjects' brains was collected for monoamine analysis. Remaining mice were assigned to one of two abstinence periods: a short 4-day (PND 36) or long 12-day (PND 44) delay after toluene exposure. Mice were then subjected to a cumulative dose response assessment of either cocaine (0, 2.5, 5, 10, 20 mg/kg; n = 60), ethanol (0, 0.5, 1, 2, 4 g/kg; n = 60), or saline (5 control injections; n = 60). Toluene concentration-dependently increased locomotor activity during exposure. When later challenged, mice exposed previously to toluene were significantly less active after cocaine (10 and 20 mg/kg) compared to air-exposed controls. Animals were also less active at the highest dose of alcohol (4 g/kg) following prior exposure to 4000 ppm when compared to air-exposed controls. Analysis of monoamines and their metabolites using High Pressure Liquid Chromatography (HPLC) within the medial prefrontal cortex (mPFC), nucleus accumbens (NAc), dorsal striatum (dSTR), and ventral tegmental area (VTA) revealed subtle effects on monoamine or metabolite levels following cumulative dosing that varied by drug (cocaine and ethanol) and abstinence duration. Our results suggest that early adolescent toluene exposure produces behavioral desensitization to subsequent cocaine-induced locomotor activity with subtle enhancement of ethanol's depressive effects and less clear impacts on levels of monoamines.

Voluntary alcohol consumption during distinct phases of adolescence differentially alters adult fear acquisition, extinction and renewal in male and female rats

Alcohol use during adolescence coincides with elevated risks of stress-related impairment in adults, particularly via disrupted developmental trajectories of vulnerable corticolimbic and mesolimbic systems involved in fear processing. Prior work has investigated the impact of binge-like alcohol consumption on adult fear and stress, but less is known about whether voluntarily consumed alcohol imparts differential effects based on adolescence phases and biological sex. Here, adolescent male and female Long Evans rats were granted daily access to alcohol (15%) during either early (Early-EtOH; P25-45) or late adolescence (Late-EtOH; P45-55) using a modified drinking-in-the-dark design. Upon adulthood (P75-80), rats were exposed to a three-context (ABC) fear renewal procedure. We found that male and female Early-EtOH rats showed faster acquisition of fear but less freezing during early phases of extinction and throughout fear renewal. In the extinction period specifically, Early-EtOH rats showed normal levels of freezing in the presence of fear-associated cues, but abnormally low freezing immediately after cue offset, suggesting a key disruption in contextual processing and/or novelty seeking brought by early adolescent binge consumption. While the effects of alcohol were most pronounced in the Early-EtOH rats (particularly in females), Late-EtOH rats displayed some changes in fear behavior including slower fear acquisition, faster extinction, and reduced renewal compared with controls, but primarily in males. Our results suggest that early adolescence in males and females and, to a lesser extent, late adolescence in males is a particularly vulnerable period wherein alcohol use can promote stress-related dysfunction in adulthood. Furthermore, our results provide multiple bases for future research focused on developmental correlates of alcohol mediated disruption in the brain.

Voluntary alcohol consumption during distinct phases of adolescence differentially alters adult fear acquisition, extinction and renewal in male and female rats

Alcohol use during adolescence coincides with elevated risks of stress-related impairment in adults, particularly via disrupted developmental trajectories of vulnerable corticolimbic and mesolimbic systems involved in fear processing. Prior work has investigated the impact of binge-like alcohol consumption on adult fear and stress, but less is known about whether voluntarily consumed alcohol imparts differential effects based on adolescence phases and biological sex. Here, adolescent male and female Long Evans rats were granted daily access to alcohol (15%) during either early (Early-EtOH; P25-45) or late adolescence (Late-EtOH; P45-55) using a modified drinking-in-the-dark design. Upon adulthood (P75-80), rats were exposed to a three-context (ABC) fear renewal procedure. We found that male and female Early-EtOH rats showed faster acquisition of fear but less freezing during early phases of extinction and throughout fear renewal. In the extinction period specifically, Early-EtOH rats showed normal levels of freezing in the presence of fear-associated cues, but abnormally low freezing immediately after cue offset, suggesting a key disruption in contextual processing and/or novelty seeking brought by early adolescent binge consumption. While the effects of alcohol were most pronounced in the Early-EtOH rats (particularly in females), Late-EtOH rats displayed some changes in fear behavior including slower fear acquisition, faster extinction, and reduced renewal compared with controls, but primarily in males. Our results suggest that early adolescence in males and females and, to a lesser extent, late adolescence in males is a particularly vulnerable period wherein alcohol use can promote stress-related dysfunction in adulthood. Furthermore, our results provide multiple bases for future research focused on developmental correlates of alcohol mediated disruption in the brain.

Differential consumption of alcohol, caffeine, and caffeinated alcohol by adolescent rats, and effects on post-adolescent gene expression signatures in the nucleus accumbens and orbitofrontal cortex

Caffeinated alcoholic beverages (CABs) are widely consumed despite little known about their behavioral and biological effects. Furthermore, CABs are also popular among adolescents, a particularly vulnerable and maturing demographic. In this preliminary study, we compared levels of daily adolescent voluntary consumption of caffeine (0.03%), alcohol (10%), caffeinated alcohol (0.03% + 10%), or vehicle and evaluated the effects of this on mRNA expression in brain regions associated with addiction and known to be affected by each drug. Beginning on postnatal day 30, rats were allowed unrestricted access to gelatin combined with one, both, or neither drug for twenty days. Compared to vehicle-consuming animals, consumption of gelatin was significantly attenuated when alcohol was included. The addition of caffeine to alcohol increased alcohol consumption in the early days of access compared to alcohol alone; however, after two weeks, alcohol consumption between these groups reached comparable levels. Compared to animals consuming caffeine alone, combining caffeine with alcohol significantly reduced caffeine intake. Targeted mRNA analysis of tissue collected from the nucleus accumbens and orbitofrontal cortex after the consumption period identified unique patterns of differentially expressed genes between treatment groups, across a broad array of neurotransmitter systems. Of particular note were genes related to a number of solute transporters and serotonergic functions. This preliminary work suggests unique pharmacological and behavioral effects from consuming caffeinated alcohol during adolescence. Since CABs are widely consumed by adolescents, these results suggest that more research into the pharmacological and behavioral effects elicited by CABs is warranted.

Motives for Cannabis Use and Risky Decision Making Influence Cannabis Use Trajectories in Teens

The current study will examine the interactive effects of motives for cannabis use (i.e., health or recreational) and risky decision making (DM) on cannabis use trajectories among adolescents. Data from 171 adolescents, aged 14-17 at the initial visit (baseline), were prospectively analyzed across five time points approximately six months apart. Latent growth curve modeling and linear regression analyses were used. We found a significant interactive effect of "recreational motives" and risky DM on the rate of cannabis use over time. Specifically, among those less likely to use cannabis for recreational purposes, riskier DM was associated with a faster increase in the rate of use over time relative to those with lower risky DM. Additionally, a significant main effect showed that those with a greater proclivity to use cannabis for health purposes had higher initial levels of use at baseline and faster increases in the rate of use over time. Regardless of risky DM, using cannabis for health purposes is associated with faster increases in cannabis use escalation. Additionally, risky DM does impact the association between recreational motives for use and cannabis use trajectories. Future work should examine these associations with additional motives for cannabis use that have been previously validated within the literature.

How Specific is Alcohol-Specific Self-Control? A Longitudinal Study of the Mediating Role of Alcohol-Specific Self-Control in the Relation Between General Self-Control and Adolescent Alcohol Use

Although accumulating studies indicate that alcohol-specific self-control can be useful in predicting adolescent alcohol use, little is known about its specificity. This longitudinal study aimed to advance our understanding of domain-specific self-control by examining whether alcohol-specific self-control mediates the effect of general self-control on adolescent alcohol use or has generalizing effects by also mediating the effect of general self-control on other behavior requiring self-control (adolescent digital media use and smoking). Data from 906 adolescents aged 11-14 years who were enrolled in the Dutch study Prevention of Alcohol Use in Students were used. Data were collected using online questionnaires at four annual measurements. Structural equation modelling revealed that higher alcohol-specific self-control fully mediated the effect of higher general self-control on alcohol use. Alcohol-specific self-control did not mediate the effect of higher general self-control on digital media use, but did partially mediate the effect of higher general self-control on smoking. These results suggest that alcohol-specific self-control is domain-specific, but not necessarily substance-specific. The domain-specificity of alcohol-specific self-control provides evidence for its theoretical relevance for the explanation of adolescent alcohol use. It also suggests leverage points for intervention programs focusing on improving alcohol-specific self-control to reduce adolescent alcohol use.

I spy with my little eye: An eye-tracking study examining adolescents' attention to alcoholic and non-alcoholic beverages in Instagram stories

Social media users are frequently exposed to alcohol images on Instagram, which in turn influences their own alcohol behaviors. Yet, it is unclear what factors drive attention to alcohol cues. In an eye-tracking study (N = 108; Mage = 16.54), we examined adolescents' attention to Instagram Stories depending on: (a) the type of beverage depicted (beer vs water), (b) the character-product interaction portrayed (CPI: peers in images shown consuming [high CPI] vs holding beverages [low CPI]) and, (c) participant's own susceptibility (high vs low-risk alcohol drinker). Our results illustrated that adolescents allocated an equal amount of attention to beer and water depicted in Instagram images. Furthermore, they devoted more attention to Instagram images wherein peers were shown consuming water and beer (high CPI) compared to those wherein peers were holding these beverages (low CPI). Surprisingly, high-risk alcohol drinkers were more responsive to both beer and water cues than low-risk drinkers. This was particularly the case for Instagram images with high CPI. These findings have implications for how health cues on Instagram are attended to and processed.

Successful word retraining, maintenance and transference of practice to everyday activities: A single case experimental design in early onset alcohol-induced brain damage

Word retraining programs have been shown to improve naming ability post-stroke and in progressive aphasias. Here, we investigated benefits for a 22-year-old Danish man (DJ), whose difficulties followed brain damage from heavy alcohol misuse. Using a multiple baseline-across-behaviours design (target behaviour: retrieval of word list items), DJ completed a 4-week "Look, Listen, Repeat" program on a computer. Ninety personally relevant target words were selected to create three matched lists. List 1 was trained for 10 sessions over 2 weeks, followed by 9 sessions for List 2 over 2 weeks, while the third list remained untrained. Naming performance was evaluated at baseline, during the intervention, and at 1 and 4 months post-training. Naming improved following each intervention block (p < .001), with only one data point overlapping between the baseline and treatment phases for trained items. Untrained words remained unchanged (p = 1.00), with 50% of data points non-overlapping across baseline to treatment phases. Performance was maintained over time, and appeared to generalize, with DJ naming more trained objects in their natural setting (85%) than untrained items (64%). While more evidence is needed, brief (20-minute), intensive (5-day/week) word retraining programs may assist word retrieval for people with brain damage associated with alcohol misuse.

Neurotoxicology of alcohol: a bibliometric and science mapping analysis

Alcohol consumption is common in many societies and has increased considerably, resulting in many socioeconomic and public health problems. In this sense, studies have been carried out in order to understand the mechanisms involved in alcohol consumption and related harmful effects. This study aimed to identify and map the knowledge and to perform bibliometric analysis of the neurotoxicology of alcohol based on the 100 most cited articles. A search was carried out in the Web of Science Core Collection database and information was extracted regarding the journal, authors, keywords, year of publication, number of citations, country and continent of the corresponding author. For each selected manuscript, the study design, alcohol exposure model, dose, period of exposure, and effect on the central nervous system and research hotspots were mapped. The journal with the highest number of publications was Alcoholism: Clinical and Experimental Research (n = 11 papers), the author who contributed the most was Crews FT (n = 8 papers), the studies had a total of 288 keywords and 75% of the publications were from the United States of America. The experimental studies evaluated the effects of prenatal and postnatal exposure and were conducted in rats and mice using doses ranging from 2.5 to 14 g/kg/day, with administration by subcutaneous, intraperitoneal, intragastric, or inhalation route or with free access through drinking bottles. Among the studies mapped, the oldest one (1989) aimed to understand the systemic damage and mechanisms of action involved, while the most recent focused on understanding the receptors and mechanisms involved in addiction, as well as genetic factors. Our results show the panorama of the most widespread scientific production in the scientific community on the neurotoxicology of ethanol, a high prevalence was observed in studies that addressed fetal alcohol syndrome and/or the effects of ethanol on neurodevelopment.

Behavioral changes and dendritic remodeling of hippocampal neurons in adolescent alcohol-treated rats

Objective: Earlier, we and others have reported that alcohol exposure in adolescent rat impaired performance of a spatial memory task in the Morris water maze. The goal of the present study was to investigate the effects of acute adolescent alcohol treatment on the hippocampus-dependent (contextual fear conditioning) and hippocampus-independent (cued fear) memories. The study also looked at the structural changes in anterior CA1 hippocampal neurons in adolescent alcohol-treated rats. Methods: Adolescent female rats were administered with a single dose of alcohol (1.0, 1.5, or 2.0 g/kg) or vehicle either before training (pre-training) or after training (pre-testing). Experimental and control rats were trained in the fear conditioning paradigm, and 24 h later tested for both contextual fear conditioning as well as cued fear memory. Separate groups of rats were treated with either alcohol (2 g/kg) or vehicle and sacrificed 24 h later. Their brains were harvested and processed for rapid Golgi staining. Randomly selected CA1 pyramidal neurons were analyzed for dendritic branching and dendritic spine density. Results: Pre-training alcohol dose-dependently attenuated acquisition of hippocampus-dependent contextual fear conditioning but had no effect on the acquisition of amygdala-associated cued fear. When administered following training (pre-testing), alcohol did not alter either contextual conditioning or cued fear memory. Golgi stained CA1 pyramidal neurons in alcohol treated female rats had reduced basilar tree branching and less complex dendritic arborization. Conclusion: Alcohol specifically impaired hippocampal learning in adolescent rats but not amygdala-associated cued fear memory. Compared to vehicle-treated rats, CA1 hippocampal pyramidal neurons in alcohol-treated rats had less complex dendritic morphology. Together, these data suggest that adolescent alcohol exposure produces changes in the neuronal organization of the hippocampus, and these changes may be related to impairments in hippocampus-dependent memory formation.

Prospective, longitudinal study to isolate the impacts of marijuana use on neurocognitive functioning in adolescents

Introduction

Policies to legalize possession and use of marijuana have been increasingly supported across the United States. Although there are restrictions on use in minors, many substance abuse scientists anticipate that these policy changes may alter use patterns among adolescents due to its wider availability and a softening of beliefs about its potentially harmful consequences. Despite the possibility that these policies may increase the prevalence of use among adolescents, the effects of marijuana on neurodevelopment remain unclear, clouding arguments in favor of or opposition to these policies.

Methods

The present prospective, longitudinal study was designed to isolate the neurodevelopmental consequences of marijuana use from its precursors during adolescence-a period of heightened vulnerability for both substance use and disrupted development due to environmental insults. Early adolescents who were substance-naïve at baseline (N = 529, aged 10-12) were recruited and tracked into adolescence when a subgroup initiated marijuana use during one of three subsequent waves of data collection, approximately 18 months apart.

Results

Results suggest that marijuana use may be specifically related to a decline in verbal learning ability in the short term and in emotion recognition, attention, and inhibition in the longer-term.

Discussion

These preliminary findings suggest that marijuana use has potential to adversely impact vulnerable neurodevelopmental processes during adolescence. Intensive additional investigation is recommended given that state-level policies regulating marijuana use and possession are rapidly shifting in the absence of good scientific information.

Resistance exercise was safe for the pregnancy and offspring's development and partially protected rats against early life stress-induced effects

Promising evidence points to gestational physical exercise as the key to preventing various disorders that affect the offspring neurodevelopment, but there are no studies showing the impact of resistance exercise on offspring health. Thus, the aim of this study was to investigate whether resistance exercise during pregnancy is able to prevent or to alleviate the possible deleterious effects on offspring, caused by early life-stress (ELS). Pregnant rats performed resistance exercise throughout the gestational period:they climbed a sloping ladder with a weight attached to their tail, 3 times a week. Male and female pups, on the day of birth (P0), were divided into 4 experimental groups: 1) rats of sedentary mothers (SED group); 2) rats of exercised mothers (EXE group); 3) rats of sedentary mothers and submitted to maternal separation (ELS group) and 4) rats of exercised mothers and submitted to MS (EXE + ELS group). From P1 to P10, pups from groups 3 and 4 were separated from their mothers for 3 h/day. Maternal behavior was assessed. From P30, behavioral tests were performed and on P38 the animals were euthanized and prefrontal cortex samples were collected. Oxidative stress and tissue damage analysis by Nissl staining were performed. Our results demonstrate that male rats are more susceptible to ELS than females, showing impulsive and hyperactive behavior similar to that seen in children with ADHD. This behavior was attenuated by the gestational resistance exercise. Our results demonstrate, for the first time, that resistance exercise performed during pregnancy seems to be safe for the pregnancy and offspring's neurodevelopment and are effective in preventing ELS-induced damage only in male rats. Interestingly, resistance exercise during pregnancy improved maternal care and it is reasonable to propose that this finding may be related to the protective role on the animals neurodevelopment, observed in our study.

Effects of current smoking severity on brain gray matter volume in opioid use disorder - a voxel-based morphometry study

Background: Cigarette smoking (CS) and opioid use disorder (OUD) significantly alter brain structure. Although OUD and cigarette smoking are highly comorbid, most prior neuroimaging research in OUD did not control for smoking severity. Specifically, the combined effect of smoking and OUD on the brain gray matter volume (GMV) remains unknown.Objectives: We used structural magnetic resonance imaging (sMRI) to examine: (1) the GMV differences between OUD and non-OUD individuals with comparable smoking severity; and (2) the differential effect of smoking severity on the brain GMV between individuals with and without OUD.Methods: We performed a secondary analysis of existing sMRI datasets of 116 individuals who smoked cigarettes daily, among whom 60 had OUD (CS-OUD; 37 male, 23 female) and 56 did not (CS; 31 male, 25 female). Brain GMV was estimated by voxel-based morphometry analysis.Results: Compared to the CS group, the CS-OUD group had a higher GMV in the occipital cortex and lower GMV in the prefrontal and temporal cortex, striatum, and pre/postcentral gyrus (whole-brain corrected-p < .05). There was a significant interaction between group and smoking severity on GMV in the medial orbitofrontal cortex (whole-brain corrected-p < .05), such that heavier smoking was associated with lower medial orbitofrontal GMV in the CS-OUD but not CS participants (r=-0.32 vs. 0.12).Conclusions: Our findings suggest a combination of independent and interactive effects of cigarette smoking and OUD on the brain gray matter. Elucidating the neuroanatomical correlates of comorbid opioid and tobacco use may shed the light on the development of novel interventions for affected individuals.

Targeting Persistent Changes in Neuroimmune and Epigenetic Signaling in Adolescent Drinking to Treat Alcohol Use Disorder in Adulthood

Studies universally find early age of drinking onset is linked to lifelong risks of alcohol problems and alcohol use disorder (AUD). Assessment of the lasting effect of drinking during adolescent development in humans is confounded by the diversity of environmental and genetic factors that affect adolescent development, including emerging personality disorders and progressive increases in drinking trajectories into adulthood. Preclinical studies using an adolescent intermittent ethanol (AIE) exposure rat model of underage binge drinking avoid the human confounds and support lifelong changes that increase risks. AIE increases adult alcohol drinking, risky decision-making, reward-seeking, and anxiety as well as reductions in executive function that all increase risks for the development of an AUD. AIE causes persistent increases in brain neuroimmune signaling high-mobility group box 1 (HMGB1), Toll-like receptor, receptor for advanced glycation end products, and innate immune genes that are also found to be increased in human AUD brain. HMGB1 is released from cells by ethanol, both free and within extracellular vesicles, that act on neurons and glia, shifting transcription and cellular phenotype. AIE-induced decreases in adult hippocampal neurogenesis and loss of basal forebrain cholinergic neurons are reviewed as examples of persistent AIE-induced pathology. Both are prevented and reversed by anti-inflammatory and epigenetic drugs. Findings suggest AIE-increased HMGB1 signaling induces the RE-1 silencing transcript blunting cholinergic gene expression, shifting neuronal phenotype. Inhibition of HMGB1 neuroimmune signaling, histone methylation enzymes, and galantamine, the cholinesterase inhibitor, both prevent and reverse AIE pathology. These findings provide new targets that may reverse AUD neuropathology as well as other brain diseases linked to neuroimmune signaling. SIGNIFICANCE STATEMENT: Adolescent underage binge drinking studies find that earlier adolescent drinking is associated with lifelong alcohol problems including high levels of lifetime alcohol use disorder (AUD). Preclinical studies find the underage binge drinking adolescent intermittent ethanol (AIE) model causes lasting changes in adults that increase risks of developing adult alcohol problems. Loss of hippocampal neurogenesis and loss of basal forebrain cholinergic neurons provide examples of how AIE-induced epigenetic and neuroimmune signaling provide novel therapeutic targets for adult AUD.

Exploring Substance Misuse Behaviors Among Black Girls in Detention: Intersections of Trauma, Sex, and Age

High risk substance misuse, trauma and gang involvement are prevalent in adolescents and often occur with youth involved with the youth punishment system. Evidence suggests that system involvement is related to trauma histories, substance misuse, as well as gang involvement. This study investigated the associations between individual and peer factors and their relationship to problem drug and alcohol use among Black girls involved with the youth punishment system. Data were collected from 188 Black girls in detention at baseline, as well as 3 and 6 month follow up periods. Measures assessed were abuse history, trauma history, sex while using drugs and alcohol, age, government assistance, and drug use. Significant findings from the multiple regression analyses indicated that younger girls were more likely to have a higher prevalence of having a drug problem than older girls at baseline. Having sex while on drugs and alcohol at the 3 month follow up period was correlated with drug use. These findings highlight how individual and peer factors can influence problem substance misuse, their behavior and peer relationships among Black girls in detention.

"We Want to See Youth That Would Be Better People Than Us": A Case Report on Addressing Adolescent Substance Use in Rural South Africa

Research suggests that substance use, particularly among adolescents may lead to increased illegal activities as well as physical and social health consequences. Around the world, communities, overburdened with adolescent and youth substance use, are finding ways to address this public health threat. Using a case study based on a focus group discussion with nine founding members, this paper reports on the case of Sibanye-a rural community coalition whose mission is to reduce the burden of adolescent substance use on families in rural South Africa. The focus group discussions were audio-recorded, transcribed verbatim, and analyzed using Nvivo 12. This work highlights the power of an engaged collective effort in addressing key community issues, even in rural areas of emerging economies where health and community infrastructure may be limited. The Sibanye coalition taps into its collective wealth of community knowledge to provide social contributions and aesthetics to help adolescents abstain from substance use and sexual risk behaviors. These activities offer adolescents safe places to meet each other, health education, and the ability to structure their free time meaningfully. Engaging community residents, particularly disadvantaged groups, should be central to any local and national strategies for promoting health and well-being.

Relationship Quality and Mental Health Implications for Adolescents during the COVID-19 Pandemic: a Longitudinal Study

Although parent-adolescent and peer-adolescent relationship quality are critical for adolescent wellbeing during typical stressful life events, the unique features of the COVID-19 pandemic put into question whether strong parent-adolescent and peer-adolescent relationship quality functioned as protective factors of adolescent mental health in this context. The current longitudinal study examined a community sample of adolescents across 3 time points, each 6 months apart (Time 1: Fall, 2019; n = 163, 50.9% male; mean age = 15.75 years, SD = 1.02). Results showed that increases in depression symptoms, perceived stress, and emotion dysregulation from Fall 2019 to Fall 2020 were predicted by changes in parent, but not peer relationship quality. The current study demonstrates that adolescent-parent relationship quality may be protective against mental health difficulties during the COVID-19 pandemic, while adolescent-peer relationship quality may not. Identifying protective factors that may play a role in mitigating the impact of the pandemic, and other such widespread health crises, on youth mental health is critical in reducing the long-term psychological harm of the viral outbreak, as well as promoting adolescent wellbeing and resilience.

Sexually dimorphic development of the mesolimbic dopamine system is associated with nuanced sensitivity to adolescent alcohol use

Alcohol use remains a major public health concern and is especially prevalent during adolescence. Adolescent alcohol use has been linked to several behavioral abnormalities in later life, including increased risk taking and impulsivity. Accordingly, when modeled in animals, male rats that had moderate alcohol consumption during adolescence exhibit multiple effects in adulthood, including increased risk taking, altered incentive learning, and greater release of dopamine in the mesolimbic pathway. It has been proposed that alcohol arrests neural development, "locking in" adolescent physiological, and consequent behavioral, phenotypes. Here we examined the feasibility that the elevated dopamine levels following adolescent alcohol exposure are a "locked in" phenotype by testing mesolimbic dopamine release across adolescent development. We found that in male rats, dopamine release peaks in late adolescence, returning to lower levels in adulthood, consistent with the notion that high dopamine levels in adolescence-alcohol-exposed adults were due to arrested development. Surprisingly, dopamine release in females was stable across the tested developmental window. This result raised a quandary that arrested dopamine levels would not differ from normal development in females and, therefore, may not contribute to pathological behavior. However, the aforementioned findings related to risk-based decision-making have only been performed in male subjects. When we tested females that had undergone adolescent alcohol use, we found that neither risk attitude during probabilistic decision-making nor mesolimbic dopamine release was altered. These findings suggest that different developmental profiles of the mesolimbic dopamine system across sexes result in dimorphic susceptibility to alcohol-induced cognitive and motivational anomalies exposure.

Does abstaining from alcohol in high school moderate intervention effects for college students? Implications for tiered intervention strategies

Brief motivational intervention (BMI) and personalized feedback intervention (PFI) are individual-focused brief alcohol intervention approaches that have been proven efficacious for reducing alcohol use among college students and young adults. Although the efficacy of these two intervention approaches has been well established, little is known about the factors that may modify their effects on alcohol outcomes. In particular, high school drinking may be a risk factor for continued and heightened use of alcohol in college, and thus may influence the outcomes of BMI and PFI. The purpose of this study was to investigate whether high school drinking was associated with different intervention outcomes among students who received PFI compared to those who received BMI. We conducted moderation analyses examining 348 mandated students (60.1% male; 73.3% White; and 61.5% first-year student) who were randomly assigned to either a BMI or a PFI and whose alcohol consumption was assessed at 4-month and 15-month follow-ups. Results from marginalized zero-inflated Poisson models showed that high school drinking moderated the effects of PFI and BMI at the 4-month follow-up but not at the 15-month follow-up. Specifically, students who reported no drinking in their senior year of high school consumed a 49% higher mean number of drinks after receiving BMI than PFI at the 4-month follow-up. The results suggest that alcohol consumption in high school may be informative when screening and allocating students to appropriate alcohol interventions to meet their different needs.

Treadmill Exercise Prevents Cognitive Impairments in Adolescent Intermittent Ethanol Rats by Reducing the Excessive Activation of Microglia Cell in the Hippocampus

The excessive activation of microglia cell induced by adolescent intermittent ethanol (AIE) leads to neuroinflammation in the hippocampus. The endocannabinoid system plays a key role in the modulation of microglia activation. Accumulating evidence suggests that regular exercise improves learning and memory deficits in AIE models. The purpose of this study was to explore the effects of treadmill exercise intervention on the cognitive performance, activation of microglia cells and the expression of monoacylglycerol lipase (MAGL), cannabinoid receptor type 1 (CB1R) and cannabinoid receptor type 2 (CB2R) in the hippocampus of AIE rats. Here, we show that AIE rats exhibited cognitive impairments, whereas the treadmill exercise improves the cognitive performance in AIE rats. In order to explore the possible mechanisms for the exercise-induced attenuation of cognitive disorder, we examined the neuroinflammation in the hippocampus. We found that treadmill exercise led to the decrease in the level of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and the increase in the level of anti-inflammatory cytokine (IL-10). In addition, we found that treadmill exercise reduced the excessive activation of the microglia cell in the hippocampus of AIE rats. Finally, we found that AIE led to a decrease in the expression of CB1R and CB2R in the hippocampus; however, the treadmill exercise further decreased the expression of CB2R in the hippocampus of AIE rats. Our results suggest that treadmill exercise attenuates AIE-induced neuroinflammation and the excessive activation of hippocampus microglial cells, which may contribute to the exercise-induced improvement of cognitive performance in AIE rats.

Self-supervised learning of neighborhood embedding for longitudinal MRI

In recent years, several deep learning models recommend first to represent Magnetic Resonance Imaging (MRI) as latent features before performing a downstream task of interest (such as classification or regression). The performance of the downstream task generally improves when these latent representations are explicitly associated with factors of interest. For example, we derived such a representation for capturing brain aging by applying self-supervised learning to longitudinal MRIs and then used the resulting encoding to automatically identify diseases accelerating the aging of the brain. We now propose a refinement of this representation by replacing the linear modeling of brain aging with one that is consistent in local neighborhoods in the latent space. Called Longitudinal Neighborhood Embedding (LNE), we derive an encoding so that neighborhoods are age-consistent (i.e., brain MRIs of different subjects with similar brain ages are in close proximity of each other) and progression-consistent, i.e., the latent space is defined by a smooth trajectory field where each trajectory captures changes in brain ages between a pair of MRIs extracted from a longitudinal sequence. To make the problem computationally tractable, we further propose a strategy for mini-batch sampling so that the resulting local neighborhoods accurately approximate the ones that would be defined based on the whole cohort. We evaluate LNE on three different downstream tasks: (1) to predict chronological age from T1-w MRI of 274 healthy subjects participating in a study at SRI International; (2) to distinguish Normal Control (NC) from Alzheimer's Disease (AD) and stable Mild Cognitive Impairment (sMCI) from progressive Mild Cognitive Impairment (pMCI) based on T1-w MRI of 632 participants of the Alzheimer's Disease Neuroimaging Initiative (ADNI); and (3) to distinguish no-to-low from moderate-to-heavy alcohol drinkers based on fractional anisotropy derived from diffusion tensor MRIs of 764 adolescents recruited by the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA). Across the three data sets, the visualization of the smooth trajectory vector fields and superior accuracy on downstream tasks demonstrate the strength of the proposed method over existing self-supervised methods in extracting information related to brain aging, which could help study the impact of substance use and neurodegenerative disorders. The code is available at https://github.com/ouyangjiahong/longitudinal-neighbourhood-embedding.

Family affluence as a protective or risk factor for adolescent drunkenness in different countries and the role drinking motives play

AIMS

Previous research has shown mixed results (positive, negative or no effects) regarding socio-economic disparities in adolescent drunkenness. This study investigates whether family affluence is differently associated with frequency of adolescent drunkenness in traditional countries, at a later diffusion of innovation adopter stage according to the Theory of Diffusions of Innovations by Rogers (2003), compared with more progressive countries at a more advanced stage. Furthermore, we investigated as to whether differences in this association can be explained by differences in adolescent drinking motives.

METHODS

This study used data from the 2009/2010 survey of the Health Behaviour in School-aged Children (HBSC) study, including 25,566 alcohol-using adolescents aged 11-19 years old from 11 European countries. The Global Innovativeness Index was used to classify countries in progressive or more traditional countries. Multi-level regression analyses and structural equation modelling were conducted.

FINDINGS

In traditional countries, family affluence showed a positive association with adolescent frequency of drunkenness. A higher endorsement of social (drinking to celebrate an event) and enhancement motives (drinking to increase moods) by adolescents with a higher family affluence mediated this positive association between family affluence and frequency of drunkenness. In progressive countries, family affluence was negatively associated with frequency of drunkenness. In these countries, a higher endorsement of coping drinking motives by adolescents with a lower family affluence mediated this association.

CONCLUSION

A country's diffusion of innovation stage (i.e., traditional vs. progressive) seems to shape the direction of the association between family affluence and adolescent drunkenness including the psychological pathways that explain these socio-economic inequalities. This is most likely due to a quicker and smoother adoption of the new 'low drunkenness norms' ('it is not cool to drink to get drunk') in progressive countries and among adolescents with a higher family affluence.

Predictors of Emergency Department Opioid Use Among Adolescents and Young Adults

OBJECTIVE

It is well established that adolescents and young adults are increasingly vulnerable to the effects of early opioid exposures, with the emergency department (ED) playing a critical role in such introduction. Our objective was to identify predictors of ED opioid administration (ED-RX) and prescribing at discharge (DC-RX) among adolescent and young adults using a machine learning approach.

METHODS

We conducted a secondary analysis of ED visit data from the National Hospital Ambulatory Medical Care Survey from 2014 to 2018. Visits where patients were aged 10 to 24 years were included. Predictors of ED-RX and DC-RX were identified via machine learning methods. Separate weighted logistic regressions were performed to determine the association between each predictor, and ED-RX and DC-RX, respectively.

RESULTS

There were 12,693 ED visits identified within the study time frame, with the majority being female (58.6%) and White (70.7%). Approximately 12.3% of all visits were administered an opioid during the ED visit, and 11.5% were prescribed one at discharge. For ED-RX, the strongest predictors were fracture injury (odds ratio [OR], 5.24; 95% confidence interval [CI], 3.73-7.35) and Southern geographic region (OR, 3.01; 95% CI, 2.14-4.22). The use of nonopioid analgesics significantly reduced the odds of ED-RX (OR, 0.46; 95% CI, 0.37-0.57). Fracture injury was also a strong predictor of DC-RX (OR, 5.91; 95% CI, 4.24-8.25), in addition to tooth pain (OR, 5.47; 95% CI, 3.84-7.69).

CONCLUSIONS

Machine learning methodologies were able to identify predictors of ED-RX and DC-RX, which can be used to inform ED prescribing guidelines and risk mitigation efforts among adolescents and young adults.

Brain Morphology Predictors of Alcohol, Tobacco, and Cannabis Use in Adolescence: A Systematic Review

In the last decade, extensive research has emerged on the predictive value of brain morphology for substance use initiation and related problems during adolescence. This systematic review provides an overview of longitudinal studies on pre-existing brain variations and later initiation of alcohol, tobacco, and cannabis use (N = 18). Adolescent structural neuroimaging studies that started before substance use initiation suggest that a smaller anterior cingulate cortex (ACC) volume, thicker or smaller superior frontal gyrus, and larger nucleus accumbens (NAcc) volume are associated with future alcohol use. Also, both smaller and larger orbitofrontal cortex (OFC) volumes were associated with future cannabis and combined alcohol/cannabis use. Smaller amygdala volumes were related to future daily tobacco smoking. These findings could point to specific vulnerabilities for adolescent substance use, as these brain areas are involved in cognitive control (ACC), reward (NAcc), motivation (OFC), and emotional memory (amygdala). However, the reported findings were inconsistent in directionality and laterality, and the largest study on alcohol use predictors reported null findings. Therefore, large population-based longitudinal studies should investigate the robustness and mechanisms of these associations. We suggested future research directions regarding sample selection, timing of baseline and follow-up measurements, and a harmonization approach of study methods.

Cumulative Stressors and Adolescent Substance Use: A Review of 21st-Century Literature

The aim of this review is to assess empirical studies from the last 2 decades that have examined the association between cumulative stressors and adolescent substance use. Cumulative stressors were measured in these studies with adverse childhood experiences or adolescent stressful life events inventories. The 109 articles meeting the eligibility criteria that emerged from the review demonstrated a consistent, yet modest, association between cumulative stressors and adolescent substance use. Of note, several studies found that the associations were moderated or mediated by genetic factors related to cortisol regulation, intrapersonal factors such as low self-control, or interpersonal factors such as peer substance use. The review's findings thus suggest that efforts to reduce the effects of cumulative stressors on substance use could gainfully identify and target these risk moderators and mediators.

Associations of Cannabis Use across Adolescence and Early Adulthood With Health and Psychosocial Adjustment in Early Adulthood and Midadulthood in Men

Background

Associations between men's prior cannabis use and their physical and psychosocial adjustment were examined using prospective data across adolescence (ages 13-20 years), early adulthood (ages 20-30 years), and midadulthood (ages 30-38 years). The theoretical framework was based in developmental-contextual and lifespan approaches.

Method

Models were tested using men in the Oregon Youth Study who had been studied since ages 9 to 10 years and who, in childhood, lived in neighborhoods with higher than average rates of delinquency. Cannabis use in adolescence was used to predict early adult outcomes (and early adult use to midadult outcomes). In addition, a set of covariates was added to the models, including childhood risk factors assessed at age 9 years (ie, family socioeconomic status; externalizing behaviors; and if available, the childhood proxy for the outcome [eg, age 9 intelligence scale]) and alcohol use in adolescence (or early adulthood). physical health outcomes included accidental injuries, problems resulting from a prior injury, body mass index, self-report health, and also pain and cardiovascular risk (blood pressure and pulse rate) in midadulthood. Psychosocial outcomes included income, housing insecurity, intelligence, depressive symptoms, psychosis symptoms, hostility/aggression, social problems, and attention problems.

Results

Whereas there was almost no prediction from prior cannabis use to the physical health outcomes, there were comprehensive associations of cannabis use from the prior developmental period and psychosocial outcomes in both early adulthood and midadulthood.

Conclusion

Cannabis use in prior developmental periods was associated with a broad range of types of poor psychosocial adjustment in adulthood.

The effect of obstructed action efficacy on reward-based decision-making in healthy adolescents: a novel functional MRI task to assay frustration

Frustration is common in adolescence and often interferes with executive functioning, particularly reward-based decision-making, and yet very little is known about how incidental frustrating events (independent of task-based feedback) disrupt the neural circuitry of reward processing in this important age group. While undergoing functional magnetic resonance imaging (fMRI), 45 healthy adolescents played a card game in which they had to guess between two options to earn points, in low- and high-stake conditions. Functioning of button presses through which they made decisions was intermittently blocked, thereby increasing frustration potential. Neural deactivation of the precuneus, a Default Mode Network region, was observed during obstructed action blocks across stake conditions, but less so on high- relative to low-stake trials. Moreover, less deactivation in goal-directed reward processing regions (i.e., caudate), frontoparietal "task control" regions, and interoceptive processing regions (i.e., somatosensory cortex, thalamus) were observed on high-stake relative to low-stake trials. These findings are consistent with less disruption of goal-directed reward seeking during blocked action efficacy in high-stake conditions among healthy adolescents. These results provide a roadmap of neural systems critical to the processing of frustrating events during reward-based decision-making in youths and could help to characterize how frustration regulation is altered in a range of pediatric psychopathologies.

Alcohol and Nicotine Use among Adolescents: An Observational Study in a Sicilian Cohort of High School Students

In recent years, the mode of alcoholic intake known as binge drinking (BD) has become a common practice, especially among adolescents who, due to socio-environmental motives, tend to reach a rapid state of drunkenness. This drunkeness leads to alterations in brain areas responsible for executive functions and cognitive processes, as well as to the genesis of factors that predispose to lasting addiction. Likewise, nicotine leads to a comparable degree of addiction. On this basis, the aim of this research was to evaluate, on a cohort of 349 high school students (15−17 years old) in the province of Palermo, the following: (I) the drinking model of alcoholic beverages; (II) the use of nicotine and the degree of dependence; (III) the correlation between the consumption of alcoholic beverages and the use of nicotine. We employed the AUDIT-C test and the Fagerström test, two valid and standard instruments, in order to assess alcohol and nicotine use, respectively. Statistical analysis of the data showed that male and female students consumed alcohol prominently in a BD mode (77.2%, audit score (AS) 3.497, confidence interval (CI) 3.206−3.788; 69.6%, AS 2.793, CI 2.412−3.274) and nicotine (41.5%, Fagerström score (FS) 3.882, CI 3.519−4.245; 28%, FS 3.286, CI 2.547−4.024). Furthermore, a positive correlation between alcohol consumption and nicotine use was found for male (r = 0.6798, p < 0.0001) and female (r = 0.6572, p < 0.0001) students. This study provided further insights into the use of legal substances of abuse in adolescents, evidencing the obvious need for the promotion of specific school educational programs aimed at the wellbeing of youth populations.

Brain structural covariance network differences in adults with alcohol dependence and heavy-drinking adolescents

BACKGROUND AND AIMS

Graph theoretic analysis of structural covariance networks (SCN) provides an assessment of brain organization that has not yet been applied to alcohol dependence (AD). We estimated whether SCN differences are present in adults with AD and heavy-drinking adolescents at age 19 and age 14, prior to substantial exposure to alcohol.

DESIGN

Cross-sectional sample of adults and a cohort of adolescents. Correlation matrices for cortical thicknesses across 68 regions were summarized with graph theoretic metrics.

SETTING AND PARTICIPANTS

A total of 745 adults with AD and 979 non-dependent controls from 24 sites curated by the Enhancing NeuroImaging Genetics through Meta Analysis (ENIGMA)-Addiction consortium, and 297 hazardous drinking adolescents and 594 controls at ages 19 and 14 from the IMAGEN study, all from Europe.

MEASUREMENTS

Metrics of network segregation (modularity, clustering coefficient and local efficiency) and integration (average shortest path length and global efficiency).

FINDINGS

The younger AD adults had lower network segregation and higher integration relative to non-dependent controls. Compared with controls, the hazardous drinkers at age 19 showed lower modularity [area-under-the-curve (AUC) difference = -0.0142, 95% confidence interval (CI) = -0.1333, 0.0092; P-value = 0.017], clustering coefficient (AUC difference = -0.0164, 95% CI = -0.1456, 0.0043; P-value = 0.008) and local efficiency (AUC difference = -0.0141, 95% CI = -0.0097, 0.0034; P-value = 0.010), as well as lower average shortest path length (AUC difference = -0.0405, 95% CI = -0.0392, 0.0096; P-value = 0.021) and higher global efficiency (AUC difference = 0.0044, 95% CI = -0.0011, 0.0043; P-value = 0.023). The same pattern was present at age 14 with lower clustering coefficient (AUC difference = -0.0131, 95% CI = -0.1304, 0.0033; P-value = 0.024), lower average shortest path length (AUC difference = -0.0362, 95% CI = -0.0334, 0.0118; P-value = 0.019) and higher global efficiency (AUC difference = 0.0035, 95% CI = -0.0011, 0.0038; P-value = 0.048).

CONCLUSIONS

Cross-sectional analyses indicate that a specific structural covariance network profile is an early marker of alcohol dependence in adults. Similar effects in a cohort of heavy-drinking adolescents, observed at age 19 and prior to substantial alcohol exposure at age 14, suggest that this pattern may be a pre-existing risk factor for problematic drinking.

Alcohol and the Adolescent Brain: What We've Learned and Where the Data Are Taking Us

This article is part of a Festschrift commemorating the 50th anniversary of the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Established in 1970, first as part of the National Institute of Mental Health and later as an independent institute of the National Institutes of Health, NIAAA today is the world's largest funding agency for alcohol research. In addition to its own intramural research program, NIAAA supports the entire spectrum of innovative basic, translational, and clinical research to advance the diagnosis, prevention, and treatment of alcohol use disorder and alcohol-related problems. To celebrate the anniversary, NIAAA hosted a 2-day symposium, "Alcohol Across the Lifespan: 50 Years of Evidence-Based Diagnosis, Prevention, and Treatment Research," devoted to key topics within the field of alcohol research. This article is based on Dr. Tapert's presentation at the event. NIAAA Director George F. Koob, Ph.D., serves as editor of the Festschrift.

Associations of delay discounting and drinking trajectories from ages 14 to 22

BACKGROUND

While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups.

METHODS

In a large-scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated-measures ANOVA was used to differentiate between high-risk and low-risk drinkers on the development of neural processing during intertemporal choices.

RESULTS

Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top-down control areas during intertemporal choices in the participants who drank more.

CONCLUSIONS

Steep DD was shown to be a predictor rather than a consequence of alcohol use in low-level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments.

Editorial: Durability of Alcohol Use Prevention Effects in Adolescents and Transitional Age Youth

Nearly 30%, or close to 2 billion, of the world's population are youth 10 to 24 years of age. This number is projected to peak in the next decade.¹ Greater focus on behaviors that are largely initiated and escalate during adolescence, and manifest ensuing morbidity and mortality in adulthood, can reduce long-term public health burden. This is especially true for alcohol use, which is the most commonly abused substance among adolescents,² and 1 of the leading causes of morbidity globally,³ with more than 4,000 alcohol-attributable deaths per year in the United States specifically.⁴ Indeed, in the United States, alcohol use among adolescents is high, with over 60% of 12^th graders reporting lifetime use, nearly 35% reporting use in the past month, and nearly 20% reporting binge drinking in the past 2 weeks.² Furthermore, approximately 5% of 12- to 17-year-olds meet criteria for an alcohol use disorder.⁵ Despite high rates of alcohol use among adolescents and poor psychosocial, neurocognitive, and health outcomes related to use, ⁶ it is estimated that only about 10% of adolescents needing substance use treatment access treatment,⁵ with 75% of those accessing treatment experiencing a relapse.⁷ Although a number of prevention and treatment interventions have demonstrated efficacy in the short term, there are few data on programs and program characteristics that result in durable treatment effects.

Examining Inhibitory Affective Processing Within the Rostral Anterior Cingulate Cortex Among Abstinent Cannabis-Using Adolescents and Young Adults

Cannabis use has been associated with deficits in self-regulation, including inhibitory control. Cannabis users have previously exhibited both structural and functional deficits in the rostral anterior cingulate cortex (rACC), a region involved in self-regulation of emotional response and inhibitory control. The present study aimed to examine whether abstinent cannabis users demonstrated abnormal functional activation and connectivity of the bilateral rACC during an emotional inhibitory processing task, and whether gender moderated these relationships. Cannabis-using (N = 34) and non-using (N = 32) participants ages 16-25 underwent at least 2-weeks of monitored substance use abstinence (excluding tobacco) and fMRI scanning while completing a Go/No-go task using fearful and calm emotional faces as non-targets. Multiple linear regression and ANCOVA were used to determine if cannabis group status was related to rACC activation and context-dependent functional connectivity, and whether gender moderated these relationships. Results showed decreased bilateral rACC activation in cannabis users during fearful response inhibition, although groups did not show any context-dependent connectivity differences between the left or right rACC during calm or fearful inhibition. Gender findings revealed that cannabis-using females compared to males did show aberrant connectivity between the right rACC and right cerebellum. These results are consistent with literature demonstrating aberrant structural and functional rACC findings and suggest that chronic cannabis use may disrupt typical rACC development-even after abstinence-potentially conferring risk for later development of mood disorders. Marginal gender-specific connectivity findings bolster continued findings regarding female vulnerability to effects of cannabis on cognition and affect. Findings should be assessed in longitudinal studies to determine causality and timing effects.

Behavioral alterations induced by intermittent ethanol intake and noise exposure in adolescent rats

Alcohol intake and exposure to noise are common activities of human adolescents performed in entertainment contexts worldwide that can induce behavioral disturbances. Therefore, the aim of the present work was to investigate in an experimental model of adolescent animals whether noise exposure and intermittent ethanol intake, when present individually or sequentially, might be able to modify different behaviors. Adolescent Wistar rats of both sexes were subjected to voluntary intermittent ethanol intake for 1 week followed by exposure to noise for 2 h and tested in a battery of behavioral tasks. Data show that males exposed to noise experienced a deficit in associative memory (AM), increase in anxiety-like behaviors (ALB) and altered reaction to novelty (RN) when compared with sham animals, whereas females also showed an increase in risk assessment behaviors (RAB) and a decrease in exploratory activity (EA). In contrast, ethanol intake induced an increase in RAB and RN in males and females, whereas females also showed a deficit in AM and EA as well as an increase in ALB. When ethanol was ingested before noise exposure, most parameters were counteracted both in male and females, but differed among sexes. In consequence, it could be hypothesized that an environmental acute stressor like noise might trigger a behavioral counteracting induced by a previous repeated exposure to a chemical agent such as ethanol, leading to a compensation of a non-adaptive behavior and reaching a better adjustment to the environment.

Protective Factors for Decreasing Nicotine, Alcohol, and Cannabis Use Among Adolescents with a History of Adverse Childhood Experiences (ACEs)

Adolescents who have experienced adversity have an increased likelihood of using substances. This study examined if individual-, family-, school-, and community-level protective factors were associated with a decreased likelihood of substance use. Data from the Well-Being and Experiences Study (the WE Study) collected from 2017 to 2018 were used. The sample was adolescents aged 14 to 17 years (N = 1002) from Manitoba, Canada. Statistical methods included descriptive statistics and logistic regression models. The prevalence of past 30-day substance use was 20.5% among boys and 29.2% among girls. Substance use was greater among adolescent girls compared to boys. Protective factors associated with an increased likelihood of not using substances included knowing culture or language, being excited for the future, picturing the future, sleeping 8 to 10 h per night (unadjusted models only), participating in non-sport activity organized by the school, having a trusted adult in the family, frequent hugs from parent, parent saying “I love you” (unadjusted models only), eating dinner together every day, mother and father understanding adolescent’s worries and problems, being able to confide in mother and father, feeling close to other students at school, having a trusted adult at school, feeling a part of school, having a trusted adult in the community (unadjusted models only), volunteering once a week or more, and feeling motivated to help and improve one’s community. Knowledge of protective factors related to decreased odds of substance use may help inform strategies for preventing substance use and ways to foster resilience among adolescents.

The Relations between Youth Cannabis Use, School Cannabis Use-Related Disciplinary Approaches and Student Perceptions of School Support

Background: In the school year immediately following cannabis legalization in Canada, this paper investigated youth perceptions of school support for the prevention and cessation of substance use. Scant research has examined student perceptions in relation to school disciplinary approaches. This study was the first to classify school discipline approach styles using school-level measures.Objective: The objective of this study was to examine whether different school cannabis use-related disciplinary approaches are associated with student cannabis use and perceptions of school supportiveness for the prevention and cessation of substance use.Results: School- and student-level survey data from Year 7 (the 2018/2019 school year) of the COMPASS study were used, including 68,037 grade 9-12 (Secondary I-V in Quebec) students attending 131 Canadian secondary schools. Schools were classified as using different cannabis use-related disciplinary styles based on school-administrator reported approaches to student first-offense violations of school cannabis policies. We identified that although none of the cannabis use-related disciplinary approach styles examined were associated with cannabis use, they were associated with student perceptions. Students attending schools classified as using a Permissive/Supportive approach had a higher likelihood of perceiving their school as supportive for substance use prevention/cessation than their peers at Authoritarian schools. Students who perceived their school as supportive for substance use prevention/cessation were less likely to report current cannabis use than their peers who perceived their school as unsupportive.Conclusions: Unlike previous studies using school classification styles that are based on student perceptions, results do not support direct associations between school cannabis use-related disciplinary styles and student cannabis use. Future prospective research should examine whether supportive disciplinary approaches (e.g., counseling referrals, educational programs) promote student perceptions of school supportiveness, and in turn, deter student substance use.

Co-occurring Mental Disorders in Transitional Aged Youth With Substance Use Disorders - A Narrative Review

Adolescence and emerging adulthood are often referred to as youth. Transitional psychiatry addresses this target group, which considers patients between 15 and 25 years of age. Substance use usually begins and peaks at this stage of life. Psychiatric disorders, foremost attention-deficit/hyperactivity disorder, and affective disorders, conduct disorders, and first-episodes psychosis frequently appear in early life stages. This review aims to provide a broad overview of transitional-aged youth's most common psychiatric comorbidities with substance use disorders. A literature search was conducted in Embase and Pubmed, and the main findings are described narratively. We present main findings for the following comorbidities: attention-deficit/hyperactivity disorder, conduct disorder, personality disorders, affective disorders, psychotic disorders, and the phenomena of overdose and suicidality. In conclusion, co-occurring mental health disorders are common and appear to facilitate the development of substance use disorders and exacerbate their overall course. Substance use also affects the severity and course of comorbid psychiatric disorders. Overall, data on transition-age youth with substance use disorders are highly inconsistent. Universal screening and treatment guidelines do not yet exist but should be aimed for in the future.

Adolescent neuroimmune function and its interaction with alcohol

Adolescence is an evolutionarily conserved developmental period associated with behavioral change, including increased risk-taking and alcohol use. Experimentation with alcohol typically begins in adolescence and transitions to binge-like patterns of consumption. Alcohol exposure during adolescence can alter normative changes in brain structure and function. Understanding mechanisms by which ethanol impacts neurodevelopmental processes is important for preventing and ameliorating the deleterious consequences of adolescent alcohol abuse. This review focuses on the neuroimmune system as a key contributor to ethanol-induced changes in adolescent brain and behavior. After brief review of neuroimmune system development, acute and chronic effects of ethanol on adolescent neuroimmune functioning are addressed. Comparisons between stress/immunological challenges and ethanol on adolescent neuroimmunity are reviewed, as cross-sensitization is relevant during adolescence. The mechanisms by which ethanol alters neuroimmune functioning are then discussed, as they may portend development of neuropathological consequences and thus increase vulnerability to subsequent challenges and potentiate addictive behaviors.

Trajectories of brain development reveal times of risk and factors promoting resilience to alcohol use during adolescence

Alcohol use disorder (AUD) is recognized as harmful for the developing brain. Numerous studies have sought environmental and genetic risk factors that predict the development of AUD, but recently identified resilience factors have emerged as protective. This chapter reviews normal processes of brain development in adolescence and emerging adulthood, delineates disturbed growth neurotrajectories related to heavy drinking, and identifies potential endogenous, experiential, and time-linked brain markers of resilience. For example, concurrent high dorsolateral prefrontal activation serving inhibitory control and low nucleus accumbens activation serving reward functions engender positive adaptation and low alcohol use. Also discussed is the role that moderating factors have in promoting risk for or resilience to AUD. Longitudinal research on the effects of all levels of alcohol drinking on the developing brain remains crucial and should be pursued in the context of resilience, which is a promising direction for identifying protective biomarkers against developing AUDs.

Regulation of glutamate signaling in the extended amygdala by adolescent alcohol exposure

Adolescence is a critical period for brain development and behavioral maturation, marked by increased risk-taking behavior and the initiation of drug use. There are significant changes in gray matter volume and pruning of synapses along with a shift in excitatory to inhibitory balance which marks the maturation of cognition and decision-making. Because of ongoing brain development, adolescents are particularly sensitive to the detrimental effects of drugs, including alcohol, which can cause long-lasting consequences into adulthood. The extended amygdala is a region critically implicated in withdrawal and negative affect such as anxiety and depression. As negative affective disorders develop during adolescence, the effects of adolescent alcohol exposure on extended amygdala circuitry needs further inquiry. Here we aim to provide a framework to discuss the existing literature on the extended amygdala, the neuroadaptations which result from alcohol use, and the intersection of factors which contribute to the long-lasting effects of this exposure.

Chronic alcohol exposure during critical developmental periods differentially impacts persistence of deficits in cognitive flexibility and related circuitry

Cognitive flexibility in decision making depends on prefrontal cortical function and is used by individuals to adapt to environmental changes in circumstances. Cognitive flexibility can be measured in the laboratory using a variety of discrete, translational tasks, including those that involve reversal learning and/or set-shifting ability. Distinct components of flexible behavior rely upon overlapping brain circuits, including different prefrontal substructures that have separable impacts on decision making. Cognitive flexibility is impaired after chronic alcohol exposure, particularly during development when the brain undergoes rapid maturation. This review examines how cognitive flexibility, as indexed by reversal and set-shifting tasks, is impacted by chronic alcohol exposure in adulthood, adolescent, and prenatal periods in humans and animal models. We also discuss areas for future study, including mechanisms that may contribute to the persistence of cognitive deficits after developmental alcohol exposure and the compacting consequences from exposure across multiple critical periods.

Alcohol and Brain Development in Adolescents and Young Adults: A Systematic Review of the Literature and Advisory Report of the Health Council of the Netherlands

Young people, whose brains are still developing, might entail a greater vulnerability to the effects of alcohol consumption on brain function and development. A committee of experts of the Health Council of the Netherlands evaluated the state of scientific knowledge regarding the question whether alcohol negatively influences brain development in young people. A systematic literature search for prospective studies was performed in PubMed and PsychINFO, for longitudinal studies of adolescents or young adults ranging between 12 and 24 y of age at baseline, investigating the relation between alcohol use and outcome measures of brain structure and activity, cognitive functioning, educational achievement, or alcohol use disorder (AUD), with measures at baseline and follow-up of the outcome of interest. Data were extracted from original articles and study quality was assessed using the Newcastle-Ottawa Scale. A total of 77 studies were included, 31 of which were of sufficient quality in relation to the study objectives. There were indications that the gray matter of the brain develops abnormally in young people who drink alcohol. In addition, the more often young people drink or the younger they start, the higher the risk of developing AUD later in life. The evidence on white matter volume or quality, brain activity, cognitive function, and educational achievement is still limited or unclear. The committee found indications that alcohol consumption can have a negative effect on brain development in adolescents and young adults and entails a risk of later AUD. The committee therefore considers it a wise choice for adolescents and young adults not to drink alcohol.

Now and then: a ten-year comparison of young people in residential substance use disorder treatment receiving group dialectical behaviour therapy

BACKGROUND

Reducing substance use in youth is a global health priority. We compared two cohorts from the same 12-week residential substance use disorder (SUD) facility over a 10 year period: Cohort A (2008-2009) and Cohort B (2018-2020). The essential components of the program remained the same with the primary treatment being dialectical behaviour therapy (DBT) plus residential milieu.

METHODS

Young people in the current Cohort B (N = 100) versus historical Cohort A (N = 102) had a similar ratio of males (74 vs. 70%) but were slightly older (mean 20.6 vs. 19.5 years). Linear mixed models were used to model outcome measures (global psychiatric symptoms, substance use severity, and quality of life) longitudinally up to 12 months later.

RESULTS

Baseline to end-of-treatment comparisons showed that the current Cohort B had overall higher levels of global psychiatric symptoms (d = 0.70), but both groups reduced psychiatric symptoms (Cohort A: d = 1.05; Cohort B: d = 0.61), and had comparable increases in confidence to resist substance use (d = 0.95). Longitudinal data from the current Cohort B showed significant decreases in substance use severity from baseline to 6-month follow-up (d = 1.83), which were sustained at 12-month follow-up (d = 0.94), and increases in quality of life from baseline to end-of-treatment (d = 0.83).

CONCLUSIONS

We demonstrate how DBT plus milieu residential care for young people continues to show positive effects in a 10-year comparison. However, youth seeking treatment today compared to 10 years ago evidenced higher acuity of psychiatric symptoms reinforcing the importance of continuous improvement of psychological treatments.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: trial ID ACTRN12618000866202 , retrospectively registered on 22/05/2018, .

Acceptance of Drug Use Mediates Future Hard Drug Use Among At-Risk Adolescent Marijuana, Tobacco, and Alcohol Users

Alternative high school (AHS) students typically report higher levels of alcohol and other drug use compared to students attending traditional high schools. Greater use of such drugs as heroin, methamphetamines, and cocaine in this at-risk population may be driven, in part, by a greater latitude of acceptance toward substance use in general, which may accelerate the transition from gateway drugs to hard drugs. Seven hundred seventy-seven adolescents (mean age 16.6; 56% female) were recruited from alternative high schools throughout Southern California. To understand the factors that may lead AHS students to use hard drugs, a model was tested in order to determine if AHS students' latitude of acceptance toward substance use was a mediator between the relationship of past use of gateway drugs and future use of hard drugs. Latitude of acceptance was found to be a statistically significant mediator of future hard drug use (b = 0.03, 95% confidence intervals = 0.01 to 0.05) among gateway drug users. An individual's latitude of acceptance to various drug use behaviors may be consistent with societal norms. However, after exposure to, or use of, gateway drugs, attitudes that are more permissive toward hard drug use may be encountered, the acceptance of hard drugs may expand, and the use of hard drugs may escalate. Interventions designed to reduce the use of hard drugs among at-risk youth may be more persuasive by crafting messages that are within the latitude of acceptance of the target population and prevent the acceptance of hard drug use.