Influences of Age, Sex, and Moderate Alcohol Drinking on the Intrinsic Functional Architecture of Adolescent Brains

Contrasting topologies of synchronous and asynchronous functional brain networks

We generated asynchronous functional networks (aFNs) using a novel method called optimal causation entropy (oCSE) and compared aFN topology to the correlation-based synchronous functional networks (sFNs) which are commonly used in network neuroscience studies. Functional magnetic resonance imaging (fMRI) time series from 212 participants of the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) study were used to generate aFNs and sFNs. As a demonstration of how aFNs and sFNs can be used in tandem, we used multivariate mixed effects models to determine whether age interacted with node efficiency to influence connection probabilities in the two networks. After adjusting for differences in network density, aFNs had higher global efficiency but lower local efficiency than the sFNs. In the aFNs, nodes with the highest outgoing global efficiency tended to be in the brainstem and orbitofrontal cortex. aFN nodes with the highest incoming global efficiency tended to be members of the Default Mode Network (DMN) in sFNs. Age interacted with node global efficiency in aFNs and node local efficiency in sFNs to influence connection probability. We conclude that the sFN and aFN both offer information about functional brain connectivity which the other type of network does not.

Age- and gender-related dispersion of brain networks across the lifespan

The effects of age and gender on large-scale resting-state networks (RSNs) reflecting within- and between-network connectivity in the healthy brain remain unclear. This study investigated how age and gender influence the brain network roles and topological properties underlying the ageing process. Ten RSNs were constructed based on 998 participants from the REST-meta-MDD cohort. Multivariate linear regression analysis was used to examine the independent and interactive influences of age and gender on large-scale RSNs and their topological properties. A support vector regression model integrating whole-brain network features was used to predict brain age across the lifespan and cognitive decline in an Alzheimer's disease spectrum (ADS) sample. Differential effects of age and gender on brain network roles were demonstrated across the lifespan. Specifically, cingulo-opercular, auditory, and visual (VIS) networks showed more incohesive features reflected by decreased intra-network connectivity with ageing. Further, females displayed distinctive brain network trajectory patterns in middle-early age, showing enhanced network connectivity within the fronto-parietal network (FPN) and salience network (SAN) and weakened network connectivity between the FPN-somatomotor, FPN-VIS, and SAN-VIS networks. Age - but not gender - induced widespread decrease in topological properties of brain networks. Importantly, these differential network features predicted brain age and cognitive impairment in the ADS sample. By showing that age and gender exert specific dispersion of dynamic network roles and trajectories across the lifespan, this study has expanded our understanding of age- and gender-related brain changes with ageing. Moreover, the findings may be useful for detecting early-stage dementia.

Differences in Brain Network Topology Based on Alcohol Use History in Adolescents

Approximately 6 million youth aged 12 to 20 consume alcohol monthly in the United States. The effect of alcohol consumption in adolescence on behavior and cognition is heavily researched; however, little is known about how alcohol consumption in adolescence may alter brain function, leading to long-term developmental detriments. In order to investigate differences in brain connectivity associated with alcohol use in adolescents, brain networks were constructed using resting-state functional magnetic resonance imaging data collected by the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) from 698 youth (12-21 years; 117 hazardous drinkers and 581 no/low drinkers). Analyses assessed differences in brain network topology based on alcohol consumption in eight predefined brain networks, as well as in whole-brain connectivity. Within the central executive network (CEN), basal ganglia network (BGN), and sensorimotor network (SMN), no/low drinkers demonstrated stronger and more frequent connections between highly globally efficient nodes, with fewer and weaker connections between highly clustered nodes. Inverse results were observed within the dorsal attention network (DAN), visual network (VN), and frontotemporal network (FTN), with no/low drinkers demonstrating weaker connections between nodes with high efficiency and increased frequency of clustered nodes compared to hazardous drinkers. Cross-sectional results from this study show clear organizational differences between adolescents with no/low or hazardous alcohol use, suggesting that aberrant connectivity in these brain networks is associated with risky drinking behaviors.

BolT: Fused window transformers for fMRI time series analysis

Deep-learning models have enabled performance leaps in analysis of high-dimensional functional MRI (fMRI) data. Yet, many previous methods are suboptimally sensitive for contextual representations across diverse time scales. Here, we present BolT, a blood-oxygen-level-dependent transformer model, for analyzing multi-variate fMRI time series. BolT leverages a cascade of transformer encoders equipped with a novel fused window attention mechanism. Encoding is performed on temporally-overlapped windows within the time series to capture local representations. To integrate information temporally, cross-window attention is computed between base tokens in each window and fringe tokens from neighboring windows. To gradually transition from local to global representations, the extent of window overlap and thereby number of fringe tokens are progressively increased across the cascade. Finally, a novel cross-window regularization is employed to align high-level classification features across the time series. Comprehensive experiments on large-scale public datasets demonstrate the superior performance of BolT against state-of-the-art methods. Furthermore, explanatory analyses to identify landmark time points and regions that contribute most significantly to model decisions corroborate prominent neuroscientific findings in the literature.

The impact of age on olfactory alcohol cue-reactivity: A functional magnetic resonance imaging study in adolescent and adult male drinkers

BACKGROUND

Adolescence is marked not only by rapid surges in the prevalence of alcohol use disorders (AUDs) but also by remarkable recovery rates, as most adolescent-onset AUDs naturally resolve over time. Little is known about the differential vulnerability of adolescents and adults. Therefore, this study aimed to unravel the moderating role of age by comparing neural alcohol cue-reactivity, an important AUD biomarker, between low-to-high beer-drinking adolescent (n = 50, 16 to 18 years), and adult (n = 51, 30 to 35 years) males matched on drinking severity.

METHODS

Associations between beer odor-induced brain activity and AUD diagnosis, severity of alcohol use-related problems, recent alcohol use, binge-drinking frequency, and task-induced craving were investigated across and between age groups in regions of interest thought to be central in alcohol cue-reactivity: the medial prefrontal cortex, anterior cingulate cortex, and striatal subregions (nucleus accumbens and caudate putamen). These analyses were complemented by exploratory whole-brain analyses.

RESULTS

Pre-task beer craving increased pre-to-post task in adolescents only. Individual differences in alcohol use, binge drinking, and craving did not relate to beer odor-induced activity. Although region-of-interest analyses did not reach significance, whole-brain analyses showed that adolescents with AUD, compared with adolescents without AUD and adults with AUD, had higher beer odor-induced activity in a large mesocorticolimbic cluster encompassing the right caudate, nucleus accumbens, orbitofrontal cortex, and the olfactory sulcus. Activity in the right caudate and putamen was positively associated with the severity of alcohol use-related problems in adolescents but negatively associated in adults.

CONCLUSION

These findings suggest a differential role of alcohol cue-reactivity in adolescents compared with adults with AUD and highlight the need for further studies investigating the role of age in the fundamental processes underlying the development of and recovery from of AUD.

Adolescent alcohol use is linked to disruptions in age-appropriate cortical thinning: an unsupervised machine learning approach

Cortical thickness changes dramatically during development and is associated with adolescent drinking. However, previous findings have been inconsistent and limited by region-of-interest approaches that are underpowered because they do not conform to the underlying spatially heterogeneous effects of alcohol. In this study, adolescents (n = 657; 12-22 years at baseline) from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study who endorsed little to no alcohol use at baseline were assessed with structural magnetic resonance imaging and followed longitudinally at four yearly intervals. Seven unique spatial patterns of covarying cortical thickness were obtained from the baseline scans by applying an unsupervised machine learning method called non-negative matrix factorization (NMF). The cortical thickness maps of all participants' longitudinal scans were projected onto vertex-level cortical patterns to obtain participant-specific coefficients for each pattern. Linear mixed-effects models were fit to each pattern to investigate longitudinal effects of alcohol consumption on cortical thickness. We found in six NMF-derived cortical thickness patterns, the longitudinal rate of decline in no/low drinkers was similar for all age cohorts. Among moderate drinkers the decline was faster in the younger adolescent cohort and slower in the older cohort. Among heavy drinkers the decline was fastest in the younger cohort and slowest in the older cohort. The findings suggested that unsupervised machine learning successfully delineated spatially coordinated patterns of vertex-level cortical thickness variation that are unconstrained by neuroanatomical features. Age-appropriate cortical thinning is more rapid in younger adolescent drinkers and slower in older adolescent drinkers, an effect that is strongest among heavy drinkers.

Evidence from "big data" for the default-mode hypothesis of ADHD: a mega-analysis of multiple large samples

We sought to identify resting-state characteristics related to attention deficit/hyperactivity disorder, both as a categorical diagnosis and as a trait feature, using large-scale samples which were processed according to a standardized pipeline. In categorical analyses, we considered 1301 subjects with diagnosed ADHD, contrasted against 1301 unaffected controls (total N = 2602; 1710 males (65.72%); mean age = 10.86 years, sd = 2.05). Cases and controls were 1:1 nearest neighbor matched on in-scanner motion and key demographic variables and drawn from multiple large cohorts. Associations between ADHD-traits and resting-state connectivity were also assessed in a large multi-cohort sample (N = 10,113). ADHD diagnosis was associated with less anticorrelation between the default mode and salience/ventral attention (B = 0.009, t = 3.45, p-FDR = 0.004, d = 0.14, 95% CI = 0.004, 0.014), somatomotor (B = 0.008, t = 3.49, p-FDR = 0.004, d = 0.14, 95% CI = 0.004, 0.013), and dorsal attention networks (B = 0.01, t = 4.28, p-FDR < 0.001, d = 0.17, 95% CI = 0.006, 0.015). These results were robust to sensitivity analyses considering comorbid internalizing problems, externalizing problems and psychostimulant medication. Similar findings were observed when examining ADHD traits, with the largest effect size observed for connectivity between the default mode network and the dorsal attention network (B = 0.0006, t = 5.57, p-FDR < 0.001, partial-r = 0.06, 95% CI = 0.0004, 0.0008). We report significant ADHD-related differences in interactions between the default mode network and task-positive networks, in line with default mode interference models of ADHD. Effect sizes (Cohen's d and partial-r, estimated from the mega-analytic models) were small, indicating subtle group differences. The overlap between the affected brain networks in the clinical and general population samples supports the notion of brain phenotypes operating along an ADHD continuum.

Blood Vessels as a Key Mediator for Ethanol Toxicity: Implication for Neuronal Damage

Excessive intake of ethanol is associated with severe brain dysfunction, and the subsequent neurological and behavioral abnormalities are well-established social risks. Many research studies have addressed how ethanol induces neurological toxicity. However, the underlying mechanisms with which ethanol induces neurological toxicity are still obscure, perhaps due to the variety and complexity of these mechanisms. Epithelial cells are in direct contact with blood and can thus mediate ethanol neurotoxicity. Ethanol activates the endothelial cells of blood vessels, as well as lymphatic vessels, in a concentration-dependent manner. Among various signaling mediators, nitric oxide plays important roles in response to ethanol. Endothelial and inducible nitric oxide synthases (eNOS and iNOS) are upregulated and activated by ethanol and enhance neuroinflammation. On the other hand, angiogenesis and blood vessel remodeling are both affected by ethanol intake, altering blood supply and releasing angiocrine factors to regulate neuronal functions. Thus, ethanol directly acts on endothelial cells, yet the molecular target(s) on endothelial cells remain unknown. Previous studies on neurons and glial cells have validated the potential contribution of membrane lipids and some specific proteins as ethanol targets, which may also be the case in endothelial cells. Future studies, based on current knowledge, will allow for a greater understanding of the contribution and underlying mechanisms of endothelial cells in ethanol-induced neurological toxicity, protecting neurological health against ethanol toxicity.

Alcohol Use Disorder and Its Comorbidity With HIV Infection Disrupts Anterior Cingulate Cortex Functional Connectivity

BACKGROUND

Individuals with alcohol use disorder (AUD) have a heightened risk of contracting HIV infection. The effects of these two diseases and their comorbidity on brain structure have been well described, but their effects on brain function have never been investigated at the scale of whole-brain connectomes.

METHODS

In contrast with prior studies that restricted analyses to specific brain networks or examined relatively small groups of participants, our analyses are based on whole-brain functional connectomes of 292 participants.

RESULTS

Relative to participants without AUD, the functional connectivity between the anterior cingulate cortex and orbitofrontal cortex was lower for participants with AUD. Compared with participants without AUD+HIV comorbidity, the functional connectivity between the anterior cingulate cortex and hippocampus was lower for the AUD+HIV participants. Compromised connectivity between these pairs was significantly correlated with greater total lifetime alcohol consumption; the effects of total lifetime alcohol consumption on executive functioning were significantly mediated by the functional connectivity between the pairs.

CONCLUSIONS

Taken together, our results suggest that the functional connectivity of the anterior cingulate cortex is disrupted in individuals with AUD alone and AUD with HIV infection comorbidity. Moreover, the affected connections are associated with deficits in executive functioning, including heightened impulsiveness.

Role of Risk Taking and Inhibitory Control in Alcohol Use Among Maltreated Adolescents and Nonmaltreated Adolescents

Exposure to childhood maltreatment is a significant risk factor for the development and persistence of problematic alcohol use. The present study examined the role of risk taking and inhibitory control, key cognitive processes believed to govern behavioral regulation, as mechanisms that underlie the association between childhood maltreatment and the early stages of alcohol use. A sample of 129 maltreated adolescents and 102 socioeconomic status-matched, nonmaltreated adolescents and their parents completed three annual assessments, including computer-administered tasks and adolescent- and parent-report questionnaires, across ages 12-13 through 14-15 years. Childhood maltreatment was not directly associated with alcohol use in middle adolescence but was significantly associated with deficits in inhibitory control in early adolescence, which, in turn, led to significantly increased alcohol use in middle adolescence. Indeed, decreased inhibitory control was significant as a mediator, highlighting the salient role of this cognitive process in the early stages of alcohol use among maltreated adolescents.

Age-related differences in the effect of chronic alcohol on cognition and the brain: a systematic review

Adolescence is an important developmental period associated with increased risk for excessive alcohol use, but also high rates of recovery from alcohol use-related problems, suggesting potential resilience to long-term effects compared to adults. The aim of this systematic review is to evaluate the current evidence for a moderating role of age on the impact of chronic alcohol exposure on the brain and cognition. We searched Medline, PsycInfo, and Cochrane Library databases up to February 3, 2021. All human and animal studies that directly tested whether the relationship between chronic alcohol exposure and neurocognitive outcomes differs between adolescents and adults were included. Study characteristics and results of age-related analyses were extracted into reference tables and results were separately narratively synthesized for each cognitive and brain-related outcome. The evidence strength for age-related differences varies across outcomes. Human evidence is largely missing, but animal research provides limited but consistent evidence of heightened adolescent sensitivity to chronic alcohol's effects on several outcomes, including conditioned aversion, dopaminergic transmission in reward-related regions, neurodegeneration, and neurogenesis. At the same time, there is limited evidence for adolescent resilience to chronic alcohol-induced impairments in the domain of cognitive flexibility, warranting future studies investigating the potential mechanisms underlying adolescent risk and resilience to the effects of alcohol. The available evidence from mostly animal studies indicates adolescents are both more vulnerable and potentially more resilient to chronic alcohol effects on specific brain and cognitive outcomes. More human research directly comparing adolescents and adults is needed despite the methodological constraints. Parallel translational animal models can aid in the causal interpretation of observed effects. To improve their translational value, future animal studies should aim to use voluntary self-administration paradigms and incorporate individual differences and environmental context to better model human drinking behavior.

Inter-Network Brain Functional Connectivity in Adolescents Assigned Female at Birth Who Experience Gender Dysphoria

Gender dysphoria (GD) is characterized by distress due to an incongruence between experienced gender and sex assigned at birth. Brain functional connectivity in adolescents who experience GD may be associated with experienced gender (vs. assigned sex) and/or brain networks implicated in own-body perception. Furthermore, sexual orientation may be related to brain functional organization given commonalities in developmental mechanisms proposed to underpin GD and same-sex attractions. Here, we applied group independent component analysis to resting-state functional magnetic resonance imaging (rs-fMRI) BOLD timeseries data to estimate inter-network (i.e., between independent components) timeseries correlations, representing functional connectivity, in 17 GD adolescents assigned female at birth (AFAB) not receiving gender-affirming hormone therapy, 17 cisgender girls, and 15 cisgender boys (ages 12-17 years). Sexual orientation was represented by degree of androphilia-gynephilia and sexual attractions strength. Multivariate partial least squares analyses found that functional connectivity differed among cisgender boys, cisgender girls, and GD AFAB, with the largest difference between cisgender boys and GD AFAB. Regarding sexual orientation and age, the brain's intrinsic functional organization of GD AFAB was both similar to and different from cisgender girls, and both differed from cisgender boys. The pattern of group differences and the networks involved aligned with the hypothesis that brain functional organization is different among GD AFAB (vs. cisgender) adolescents, and certain aspects of this organization relate to brain areas implicated in own-body perception and self-referential thinking. Overall, brain functional organization of GD AFAB was generally more similar to that of cisgender girls than cisgender boys.

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.

Growth trajectories of cognitive and motor control in adolescence: How much is development and how much is practice?

OBJECTIVE

Executive control continues to develop throughout adolescence and is vulnerable to alcohol use. Although longitudinal assessment is ideal for tracking executive function development and onset of alcohol use, prior testing experience must be distinguished from developmental trajectories.

METHOD

We used the Stroop Match-to-Sample task to examine the improvement of processing speed and specific cognitive and motor control over 4 years in 445 adolescents. The twice-minus-once-tested method was used and expanded to four test sessions to delineate prior experience (i.e., learning) from development. A General Additive Model evaluated the predictive value of age and sex on executive function development and potential influences of alcohol use on development.

RESULTS

Results revealed strong learning between the first two assessments. Adolescents significantly improved their speed processing over 4 years. Compared with boys, girls enhanced ability to control cognitive interference and motor reactions. Finally, the influence of alcohol use initiation was tested over 4 years for development in 110 no/low, 110 moderate/heavy age- and sex-matched drinkers; alcohol effects were not detected in the matched groups.

CONCLUSIONS

Estimation of learning effects is crucial for examining developmental changes longitudinally. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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.

Sex-specific frontal-striatal connectivity differences among adolescents with externalizing disorders

BACKGROUND

Sex-specific neurobiological underpinnings of impulsivity in youth with externalizing disorders have not been well studied. The only report of functional connectivity (FC) findings in this area demonstrated sex differences in fronto-subcortical connectivity in youth with attention-deficit/hyperactivity disorder (ADHD).

METHODS

The current study used functional magnetic resonance imaging(fMRI) to examine sex differences in resting-state seed-based FC, self-rated impulsivity, and their interactions in 11-12-year-old boys (n = 43) and girls (n = 43) with externalizing disorders. Generalized linear models controlling for pubertal development were used. Seeds were chosen in the ventral striatum, medial prefrontal cortex, middle frontal gyrus and amygdala.

RESULTS

Impulsivity scores were greater in boys than girls (p < 0.05). Boys showed greater positive connectivity within a ventromedial prefrontal-ventral striatal network. In addition, boys demonstrated weaker connectivity than girls within two medial-lateral prefrontal cortical networks. However, only boys showed greater medial-lateral prefrontal connectivity correlated with greater impulsivity.

CONCLUSIONS

The findings provide evidence supporting sex differences in both ventral striatal-ventromedial prefrontal and medial-lateral prefrontal functional networks in youth with externalizing disorders. These important networks are thought to be implicated in impulse control. Medial-lateral prefrontal connectivity may represent a male-specific biomarker of impulsivity.

Adolescent alcohol use disrupts functional neurodevelopment in sensation seeking girls

Exogenous causes, such as alcohol use, and endogenous factors, such as temperament and sex, can modulate developmental trajectories of adolescent neurofunctional maturation. We examined how these factors affect sexual dimorphism in brain functional networks in youth drinking below diagnostic threshold for alcohol use disorder (AUD). Based on the 3-year, annually acquired, longitudinal resting-state functional magnetic resonance imaging (MRI) data of 526 adolescents (12-21 years at baseline) from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) cohort, developmental trajectories of 23 intrinsic functional networks (IFNs) were analyzed for (1) sexual dimorphism in 259 participants who were no-to-low drinkers throughout this period; (2) sex-alcohol interactions in two age- and sex-matched NCANDA subgroups (N = 76 each), half no-to-low, and half moderate-to-heavy drinkers; and (3) moderating effects of gender-specific alcohol dose effects and a multifactorial impulsivity measure on IFN connectivity in all NCANDA participants. Results showed that sex differences in no-to-low drinkers diminished with age in the inferior-occipital network, yet girls had weaker within-network connectivity than boys in six other networks. Effects of adolescent alcohol use were more pronounced in girls than boys in three IFNs. In particular, girls showed greater within-network connectivity in two motor networks with more alcohol consumption, and these effects were mediated by sensation-seeking only in girls. Our results implied that drinking might attenuate the naturally diminishing sexual differences by disrupting the maturation of network efficiency more severely in girls. The sex-alcohol-dose effect might explain why women are at higher risk of alcohol-related health and psychosocial consequences than men.

Regional growth trajectories of cortical myelination in adolescents and young adults: longitudinal validation and functional correlates

Adolescence is a time of continued cognitive and emotional evolution occurring with continuing brain development involving synaptic pruning and cortical myelination. The hypothesis of this study is that heavy myelination occurs in cortical regions with relatively direct, predetermined circuitry supporting unimodal sensory or motor functions and shows a steep developmental slope during adolescence (12-21 years) until young adulthood (22-35 years) when further myelination decelerates. By contrast, light myelination occurs in regions with highly plastic circuitry supporting complex functions and follows a delayed developmental trajectory. In support of this hypothesis, cortical myelin content was estimated and harmonized across publicly available datasets provided by the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) and the Human Connectome Project (HCP). The cross-sectional analysis of 226 no-to-low alcohol drinking NCANDA adolescents revealed relatively steeper age-dependent trajectories of myelin growth in unimodal primary motor cortex and flatter age-dependent trajectories in multimodal mid/posterior cingulate cortices. This pattern of continued myelination showed smaller gains when the same analyses were performed on 686 young adults of the HCP cohort free of neuropsychiatric diagnoses. Critically, a predicted correlation between a motor task and myelin content in motor or cingulate cortices was found in the NCANDA adolescents, supporting the functional relevance of this imaging neurometric. Furthermore, the regional trajectory slopes were confirmed by performing longitudinally consistent analysis of cortical myelin. In conclusion, coordination of myelin content and circuit complexity continues to develop throughout adolescence, contributes to performance maturation, and may represent active cortical development climaxing in young adulthood.

Spatio-Temporal Graph Convolution for Resting-State fMRI Analysis

The Blood-Oxygen-Level-Dependent (BOLD) signal of resting-state fMRI (rs-fMRI) records the temporal dynamics of intrinsic functional networks in the brain. However, existing deep learning methods applied to rs-fMRI either neglect the functional dependency between different brain regions in a network or discard the information in the temporal dynamics of brain activity. To overcome those shortcomings, we propose to formulate functional connectivity networks within the context of spatio-temporal graphs. We train a spatio-temporal graph convolutional network (ST-GCN) on short sub-sequences of the BOLD time series to model the non-stationary nature of functional connectivity. Simultaneously, the model learns the importance of graph edges within ST-GCN to gain insight into the functional connectivities contributing to the prediction. In analyzing the rs-fMRI of the Human Connectome Project (HCP, N = 1,091) and the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA, N = 773), ST-GCN is significantly more accurate than common approaches in predicting gender and age based on BOLD signals. Furthermore, the brain regions and functional connections significantly contributing to the predictions of our model are important markers according to the neuroscience literature.

The effect of alcohol use on neuroimaging correlates of cognitive and emotional processing in human adolescence

OBJECTIVE

This article provides an overview of the scientific literature pertaining to the effects of alcohol on neural correlates of cognitive and emotional functioning, including reward processing and cue-reactivity, in adolescence and young adulthood.

METHOD

Peer-reviewed, original research articles that included a neuroimaging assessment of alcohol effects on subsequent cognitive or emotional processing in adolescent or young adult samples were searched (through November 2018) and summarized in the review.

RESULTS

Cross-sectional studies provided early evidence of alcohol-related differences in neural processing across a number of cognitive domains. Longitudinal studies have identified neural abnormalities that predate drinking within most domains of cognitive functioning, while a few neural alterations have been observed within the domains of visual working memory, inhibitory control, reward processing, and cue-reactivity that appear to be related to the neurotoxic effect of alcohol use during adolescence. In contrast, neural correlates of emotion functioning appear to be relatively stable to the effects of alcohol.

CONCLUSIONS

Larger prospective studies are greatly needed to disentangle premorbid factors from neural consequences associated with drinking, and to detect subsets of youth who may be particularly vulnerable to alcohol's effects on cognitive and emotional functioning. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Five-Year Incidence of Hospital-Based Emergencies Related to Acute Recreational Intoxication in Minors

BACKGROUND

Alcohol or other drug (AOD) intoxication in minors is a public health challenge. We characterized underage patients admitted to an emergency department (ED) with acute, recreational AOD intoxication.

METHODS

We conducted a 5-year (2012 to 2016) analysis of minors admitted to the only hospital-based pediatric ED in an urban area. Episodes of AOD intoxication were selected using ICD-9-CM diagnostic codes. Sociodemographics, substance use and clinical characteristics, laboratory parameters, and discharge dispositions were collected through the revision of clinical charts.

RESULTS

A total of 266 admissions related to recreational AOD intoxication in 258 patients occurred during the study period. Among the 258 patients, 127 (49.2%) were men, median age 16 years [IQR: 15 to 17 years], and 234 (90.7%) of episodes were alcohol-related. At admission, 202/256 (78.9%) patients had a Glasgow Coma Scale ≥ 13 points, the median systolic and diastolic blood pressure was 109 mmHg (IQR: 101 to 118 mmHg) and 67 mmHg (IQR: 60 to 73 mmHg), respectively, and the median blood glucose level was 112 mg/dl (IQR: 99 to 127 mg/dl). Only 72/258 (27.9%) patients underwent urine screening (22/72 (30.5%) were positive for cannabis), and only 30/258 (11.6%) were tested for blood ethanol (median: 185 mg/dl, IQR: 163 to 240 mg/dl). There was a trend in admissions occurring early in the morning of weekend days, and 249 (96.5%) patients were discharged home the day of admission.

CONCLUSIONS

Though the severity of AOD intoxication seems to be mild to moderate, assessment of substance exposure is low and may underestimate polydrug use in underage populations.

Variational Autoencoder with Truncated Mixture of Gaussians for Functional Connectivity Analysis

Resting-state functional connectivity states are often identified as clusters of dynamic connectivity patterns. However, existing clustering approaches do not distinguish major states from rarely occurring minor states and hence are sensitive to noise. To address this issue, we propose to model major states using a non-linear generative process guided by a Gaussian-mixture distribution in a low-dimensional latent space, while separately modeling the connectivity patterns of minor states by a non-informative uniform distribution. We embed this truncated Gaussian-Mixture model in a Variational Autoencoder framework to obtain a general joint clustering and outlier detection approach, tGM-VAE. When applied to synthetic data with known ground-truth, tGM-VAE is more accurate in clustering connectivity patterns than existing approaches. On the rs-fMRI of 593 healthy adolescents, tGM-VAE identifies meaningful major connectivity states. The dwell time of these states significantly correlates with age.

Distribution of brain iron accrual in adolescence: Evidence from cross-sectional and longitudinal analysis

To track iron accumulation and location in the brain across adolescence, we repurposed diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) data acquired in 513 adolescents and validated iron estimates with quantitative susceptibility mapping (QSM) in 104 of these subjects. DTI and fMRI data were acquired longitudinally over 1 year in 245 male and 268 female, no-to-low alcohol-consuming adolescents (12-21 years at baseline) from the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) study. Brain region average signal values were calculated for susceptibility to nonheme iron deposition: pallidum, putamen, dentate nucleus, red nucleus, and substantia nigra. To estimate nonheme iron, the corpus callosum signal (robust to iron effects) was divided by regional signals to generate estimated R2 (edwR2 for DTI) and R2 * (eR2 * for fMRI). Longitudinal iron deposition was measured using the normalized signal change across time for each subject. Validation using baseline QSM, derived from susceptibility-weighted imaging, was performed on 46 male and 58 female participants. Normalized iron deposition estimates from DTI and fMRI correlated with age in most regions; both estimates indicated less iron in boys than girls. QSM results correlated highly with DTI and fMRI results (adjusted R2 = 0.643 for DTI, 0.578 for fMRI). Cross-sectional and longitudinal analyses indicated an initial rapid increase in iron, notably in the putamen and red nucleus, that slowed with age. DTI and fMRI data can be repurposed for identifying regional brain iron deposition in developing adolescents as validated with high correspondence with QSM.

A dual process perspective on advances in cognitive science and alcohol use disorder

There is a tremendous global and national (US) burden associated with alcohol misuse and alcohol use disorder (AUD). Further, of the mental health disorders, AUD has the widest treatment gap. Thus, there is a critical need for improved understanding of the etiology, maintenance, and treatment of AUD. The application of cognitive science to the study of AUD has a longstanding history of attempting to meet this need. In this selective review, we identified and focused on four domains of recent (i.e., in the last decade) applications of cognitive science to the study of AUD: implicit cognitive biases, executive function, behavioral economic approaches to alcohol decision making, and functional connectivity neuroimaging. We highlighted advances within these four domains and considered them in the context of dual process models of addiction, which focus on the contribution and interplay of two complementary neurocognitive systems (impulsive and control systems). Findings across the domains were generally consistent with dual process models. They also suggest the need for further model refinements, including integrating behavioral economic approaches and findings from functional connectivity neuroimaging studies. Research evaluating candidate interventions associated with these domains is emergent but promising, suggesting important directions for future research.

Effects of age, sex, and puberty on neural efficiency of cognitive and motor control in adolescents

Critical changes in adolescence involve brain cognitive maturation of inhibitory control processes that are essential for a myriad of adult functions. Cognitive control advances into adulthood as there is more flexible integration of component processes, including inhibitory control of conflicting information, overwriting inappropriate response tendencies, and amplifying relevant responses for accurate execution. Using a modified Stroop task with fMRI, we investigated the effects of age, sex, and puberty on brain functional correlates of cognitive and motor control in 87 boys and 91 girls across the adolescent age range. Results revealed dissociable brain systems for cognitive and motor control processes, whereby adolescents flexibly adapted neural responses to control demands. Specifically, when response repetitions facilitated planning-based action selection, frontoparietal-insular regions associated with cognitive control operations were less activated, whereas cortical-pallidal-cerebellar motor regions associated with motor skill acquisition, were more activated. Attenuated middle cingulate cortex activation occurred with older adolescent age for both motor control and cognitive control with automaticity from repetition learning. Sexual dimorphism for control operations occurred in extrastriate cortices involved in visuo-attentional selection: While boys enhanced extrastriate selection processes for motor control, girls activated these regions more for cognitive control. These sex differences were attenuated with more advanced pubertal stage. Together, our findings show that brain cognitive and motor control processes are segregated, demand-specific, more efficient in older adolescents, and differ between sexes relative to pubertal development. Our findings advance our understanding of how distributed brain activity and the neurodevelopment of automaticity enhances cognitive and motor control ability in adolescence.

Longitudinally consistent estimates of intrinsic functional networks

Increasing numbers of neuroimaging studies are acquiring data to examine changes in brain architecture by investigating intrinsic functional networks (IFN) from longitudinal resting-state functional MRI (rs-fMRI). At the subject level, these IFNs are determined by cross-sectional procedures, which neglect intra-subject dependencies and result in suboptimal estimates of the networks. Here, a novel longitudinal approach simultaneously extracts subject-specific IFNs across multiple visits by explicitly modeling functional brain development as an essential context for seeking change. On data generated by an innovative simulation based on real rs-fMRI, the method was more accurate in estimating subject-specific IFNs than cross-sectional approaches. Furthermore, only group-analysis based on longitudinally consistent estimates identified significant developmental effects within IFNs of 246 adolescents from the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) study. The findings were confirmed by the cross-sectional estimates when the corresponding group analysis was confined to the developmental effects. Those effects also converged with current concepts of neurodevelopment.

Unlimited sucrose consumption during adolescence generates a depressive-like phenotype in adulthood

Depression is highly prevalent worldwide, but its etiology is not fully understood. An overlooked possible contributor to the epidemic of depression is feeding styles, particularly at early age when the brain is intensely changing. We have previously reported that unlimited sucrose consumption during adolescence leads to enduring changes in brain reward function. Here, we tested the hypothesis that sucrose consumption during adolescence would lead to a 'depressive-like' phenotype. Adolescent male rats were given unlimited access to 5% sucrose in their home cages from postnatal day 30 to postnatal day 46 and their emotional behavior was subsequently examined at adulthood. Sucrose consumption during adolescence caused anhedonia, decreased motivation for saccharin, increased immobility in the forced swim test and exacerbated anxiety-like behavior. Additionally, sucrose consumption during adolescence decreased cell proliferation in the hippocampus in adulthood. Chronic treatment with imipramine (10 mg/kg) normalized behavior and restored cell proliferation in the hippocampus of adult rats with a history of sucrose consumption during adolescence. A similar sucrose consumption starting at adulthood only increases immobility in the forced swim test, suggesting that sucrose intake affects also adults' behavior but to a lesser degree. Overall, our findings reveal an unsuspected protracted effect of sucrose consumption on behavior and suggest that unlimited sucrose consumption during critical periods of brain development may play an important role in the etiology of reward-related disorders such as depression.

A Riemannian Framework for Longitudinal Analysis of Resting-State Functional Connectivity

Even though the number of longitudinal resting-state-fMRI studies is increasing, accurately characterizing the changes in functional connectivity across visits is a largely unexplored topic. To improve characterization, we design a Riemannian framework that represents the functional connectivity pattern of a subject at a visit as a point on a Riemannian manifold. Geodesic regression across the 'sample' points of a subject on that manifold then defines the longitudinal trajectory of their connectivity pattern. To identify group differences specific to regions of interest (ROI), we map the resulting trajectories of all subjects to a common tangent space via the Lie group action. We account for the uncertainty in choosing the common tangent space by proposing a test procedure based on the theory of latent p-values. Unlike existing methods, our proposed approach identifies sex differences across 246 subjects, each of them being characterized by three rs-fMRI scans.

Alcohol Consumption during Adolescence in a Mouse Model of Binge Drinking Alters the Intrinsic Excitability and Function of the Prefrontal Cortex through a Reduction in the Hyperpolarization-Activated Cation Current

Periodic episodes of excessive alcohol consumption ("binge drinking") occur frequently among adolescents, and early binge drinking is associated with an increased risk of alcohol use disorders later in life. The PFC undergoes significant development during adolescence and hence may be especially susceptible to the effects of binge drinking. In humans and in animal models, adolescent alcohol exposure is known to alter PFC neuronal activity and produce deficits in PFC-dependent behaviors, such as decision making, response inhibition, and working memory. Using a voluntary intermittent access to alcohol (IA EtOH) procedure in male mice, we demonstrate that binge-level alcohol consumption during adolescence leads to altered drinking patterns and working memory deficits in young adulthood, two outcomes that suggest medial PFC dysfunction. We recorded from pyramidal neurons (PNs) in the prelimbic subregion of the medial PFC in slices obtained from mice that had IA EtOH and found that they display altered excitability, including a hyperpolarization of the resting membrane potential and reductions in the hyperpolarization-activated cation current (I_h) and in intrinsic persistent activity (a mode of neuronal firing that is dependent on I_h). Many of these effects on intrinsic excitability were sustained following abstinence and observed in mice that showed working memory deficits. In addition, we found that resting membrane potential and the I_h-dependent voltage "sag" in prelimbic PFC PNs are developmentally regulated during adolescence, suggesting that adolescent alcohol exposure may compromise PFC function by arresting the normal developmental trajectory of PN intrinsic excitability.SIGNIFICANCE STATEMENT Binge alcohol drinking during adolescence has negative consequences for the function of the developing PFC. Using a mouse model of voluntary binge drinking during adolescence, we found that this behavior leads to working memory deficits and altered drinking behavior in adulthood. In addition, we found that adolescent drinking is associated with specific changes to the intrinsic excitability of pyramidal neurons in the PFC, reducing the ability of these neurons to generate intrinsic persistent activity, a phenomenon thought to be important for working memory. These findings may help explain why human adolescent binge drinkers show performance deficits on tasks mediated by the PFC.

Adolescent brain cognitive development (ABCD) study: Overview of substance use assessment methods

One of the objectives of the Adolescent Brain Cognitive Development (ABCD) Study (https://abcdstudy.org/) is to establish a national longitudinal cohort of 9 and 10 year olds that will be followed for 10 years in order to prospectively study the risk and protective factors influencing substance use and its consequences, examine the impact of substance use on neurocognitive, health and psychosocial outcomes, and to understand the relationship between substance use and psychopathology. This article provides an overview of the ABCD Study Substance Use Workgroup, provides the goals for the workgroup, rationale for the substance use battery, and includes details on the substance use module methods and measurement tools used during baseline, 6-month and 1-year follow-up assessment time-points. Prospective, longitudinal assessment of these substance use domains over a period of ten years in a nationwide sample of youth presents an unprecedented opportunity to further understand the timing and interactive relationships between substance use and neurocognitive, health, and psychopathology outcomes in youth living in the United States.

Parameter-Free Centralized Multi-Task Learning for Characterizing Developmental Sex Differences in Resting State Functional Connectivity

In contrast to most existing studies that typically characterize the developmental sex differences using analysis of variance or equivalently multiple linear regression, we present a parameter-free centralized multi-task learning method to identify sex specific and common resting state functional connectivity (RSFC) patterns underlying the brain development based on resting state functional MRI (rs-fMRI) data. Specifically, we design a novel multi-task learning model to characterize sex specific and common RSFC patterns in an age prediction framework by regarding the age prediction for males and females as separate tasks. Moreover, the importance of each task and the balance of these two patterns, respectively, are automatically learned in order to make the multi-task learning robust as well as free of tunable parameters, i.e., parameter-free for short. Our experimental results on synthetic datasets verified the effectiveness of our method with respect to prediction performance, and experimental results on rs-fMRI scans of 1041 subjects (651 males) of the Philadelphia Neurodevelopmental Cohort (PNC) showed that our method could improve the age prediction on average by 5.82% with statistical significance than the best alternative methods under comparison, in addition to characterizing the developmental sex differences in RSFC patterns.

Neural Correlates of Rewarded Response Inhibition in Youth at Risk for Problematic Alcohol Use

Risk for substance use disorder (SUD) is associated with poor response inhibition and heightened reward sensitivity. During adolescence, incentives improve performance on response inhibition tasks and increase recruitment of cortical control areas (Geier et al., 2010) associated with SUD (Chung et al., 2011). However, it is unknown whether incentives moderate the relationship between response inhibition and trait-level psychopathology and personality features of substance use risk. We examined these associations in the current project using a rewarded antisaccade (AS) task (Geier et al., 2010) in youth at risk for substance use. Participants were 116 adolescents and young adults (ages 12–21) from the University of Pittsburgh site of the National Consortium on Adolescent Neurodevelopment and Alcohol [NCANDA] study, with neuroimaging data collected at baseline and 1 year follow up visits. Building upon previous work using this task in normative developmental samples (Geier et al., 2010) and adolescents with SUD (Chung et al., 2011), we examined both trial-wise BOLD responses and those associated with individual task-epochs (cue presentation, response preparation, and response) and associated them with multiple substance use risk factors (externalizing and internalizing psychopathology, family history of substance use, and trait impulsivity). Results showed that externalizing psychopathology and high levels of trait impulsivity (positive urgency, SUPPS-P) were associated with general decreases in antisaccade performance. Accompanying this main effect of poor performance, positive urgency was associated with reduced recruitment of the frontal eye fields (FEF) and inferior frontal gyrus (IFG) in both a priori regions of interest and at the voxelwise level. Consistent with previous work, monetary incentive improved antisaccade behavioral performance and was associated with increased activation in the striatum and cortical control areas. However, incentives did not moderate the association between response inhibition behavioral performance and any trait-level psychopathology and personality factor of substance use risk. Reward interactions were observed for BOLD responses at the task-epoch level, however, they were inconsistent across substance use risk types. The results from this study may suggest poor response inhibition and heightened reward sensitivity are not overlapping neurocognitive features of substance use risk. Alternatively, more subtle, common longitudinal processes might jointly explain reward sensitivity and response inhibition deficits in substance use risk.