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Research Interests: Addiction Medicine, Adolescent, Medicine, Drug, Affect, and 15 moreProspective studies, Humans, Child, Substance Abuse, Male, Young Adult, Risk factors, Longitudinal Studies, Adult, Public health systems and services research, Longitudinal Study, Risk Factors, Self report, Substance-Related Disorders, and Psychiatric Status Rating Scales
Research Interests: Psychology, Adolescent, Medicine, Prospective studies, Humans, and 15 moreChild, Internal Medicine, Testosterone, Male, Young Adult, Follow-up studies, Risk factors, tESTIS, Longitudinal Studies, Hormone, Risk Factors, Psychology and Cognitive Sciences, hydrocortisone, Medical and Health Sciences, and Residence Characteristics
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Research Interests: Adolescent Development, Adolescent, Medicine, Biological Sciences, Biological Psychiatry, and 15 moreHumans, Child, Behaviour, Hormones, Male, Etiology, Cannabis, Longitudinal Studies, Analysis of Variance, Drug Users, Likelihood Functions, Case Control Studies, Cohort Studies, Marijuana abuse, and Medical and Health Sciences
Research Interests: Psychology, Clinical Psychology, Developmental Psychology, Parenting, Medicine, and 15 moreHumans, Child, Substance Abuse, Child Abuse, Infant, Drug abuse, Neglect, Parents, Adult, Substance-Related Disorders, Substance Use Disorder, Child Neglect, Child preschool, High risk, and Environmental factor
Research Interests: Psychology, Medicine, Population, Humans, Child, and 15 moreNeeds Assessment, Female, Male, Cluster Analysis, Risk factors, Pennsylvania, Geospatial Analysis, Parents, Public health systems and services research, Risk Factors, Disinhibition, Community Based Mental Health Services, Metropolitan Area, Impulsive behavior, and Residence Characteristics
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Research Interests: Psychology, Addiction, Psychometrics, Item Response Theory, Risk assessment, and 15 moreAdolescent, Causality, Medicine, Twins, Humans, Female, Computerized Adaptive Testing, Male, Young Adult, Liability, Risk Assessment, Predictive value of tests, Marijuana abuse, Psychology and Cognitive Sciences, and Medical and Health Sciences
Research Interests: Genetics, Addiction, Adolescent, Fathers, Medicine, and 15 moreHumans, Child, Male, Conduct Disorder, Etiology, Pennsylvania, African Americans, Cannabis, Peer group, Longitudinal Studies, European Continental Ancestry Group, Housekeeping, Cooperative Behavior, Marijuana abuse, and Medical and Health Sciences
Research Interests: Chemistry, Epidemiology, Assessment, Adolescent, Medicine, and 15 moreHumans, Child, Alcoholism, Female, Male, Ethanol, Data Collection, Longitudinal Studies, Adult, Age Factors, Indexation, Clinical Trials as Topic, health status indicators, Psychology and Cognitive Sciences, and Medical and Health Sciences
Research Interests: Psychology, Socialization, Risk, Adolescent, Causality, and 15 moreFathers, Medicine, Humans, Child, Smoking, Alcohol Drinking, Male, Cannabis, Peer group, Street Drugs, Psychological Theory, Marijuana abuse, Psychiatric Status Rating Scales, Psychology and Cognitive Sciences, and Medical and Health Sciences
Research Interests: Juvenile Delinquency, Adolescent, Medicine, Comorbidity, Probability, and 15 moreDrug, Drug Use, Prospective studies, Humans, Child, Male, Drug Addiction, American, Adult, Age Factors, Risk Factors, Adolescent Behavior, Marijuana abuse, Psychology and Cognitive Sciences, and Medical and Health Sciences
Variation in the risk for and severity of substance use disorders (SUD) in the population is caused by multiple organismic (genetic, biochemical, psychological) and environmental factors. Whereas drug- or drug-class-specific liability... more
Variation in the risk for and severity of substance use disorders (SUD) in the population is caused by multiple organismic (genetic, biochemical, psychological) and environmental factors. Whereas drug- or drug-class-specific liability mechanisms exist, a substantial proportion of variance in the risk is shared between specific liabilities, reflecting mechanisms that determine common liability to SUD. Data from epidemiologic, clinical, psychological, physiological, biochemical, and family and genetic studies reviewed in this paper indicate the existence of mechanisms and characteristics shared in common by liabilities to SUD related to different drugs. These mechanisms can be conceptualized as common liability to SUD, a latent trait accounting for a substantial portion of variation in SUD risk and severity and determined by all factors influencing the probability of SUD development. An accompanying paper describes an approach to the quantitative estimation of this trait.
Research Interests: Genetics, Neuroscience, Psychology, Addiction, Causality, and 15 moreMedicine, Disease susceptibility, Humans, Etiology, Risk factors, Drug abuse, Phenotype, Liability, Sex Factors, Risk Factors, Complex Traits, Brain Chemistry, Psychology and Cognitive Sciences, Medical and Health Sciences, and Environmental factor
Research Interests: Psychology, Clinical Psychology, Psychiatry, Psychometrics, Item Response Theory, and 15 moreMedicine, Drug, Humans, Female, Male, Drug Addiction, Psychosocial, Mental Disorder, Adult, Prognosis, American Psychiatric Association, Indexation, Psychological Models, Severity of Illness Index, and Diagnostic and Statistical Manual
Research Interests: Psychology, Clinical Psychology, Adolescent, Medicine, Humans, and 13 moreChild, Substance Abuse, Male, Addictive Behaviours, Young Adult, Conduct Disorder, Risk factors, Intergenerational Relations, Longitudinal Studies, Addictive Behaviors, Risk Factors, Substance-Related Disorders, and Affective symptoms
Previous research has shown that a trait termed neurobehavior disinhibition (ND) measured in childhood predicts substance use disorder by young adulthood. The present investigation extends these findings by determining the degree to which... more
Previous research has shown that a trait termed neurobehavior disinhibition (ND) measured in childhood predicts substance use disorder by young adulthood. The present investigation extends these findings by determining the degree to which peer environment mediates the association between ND and development of cannabis use disorder (CUD). ND was measured in a sample of 216 boys 10-12 years of age. The peer environment was assessed at age 16. Current CUD was determined at age 22. Paternal and maternal SUD predicted son's ND which, in turn, predicted son's peer environment and, subsequently, son's cannabis use frequency and CUD. Peer environment mediated the association between ND and cannabis use and ND and CUD. Maternal and paternal SUD predicted the peer environment. Parental SUD, son's ND, and son's peer environment predicted CUD at age 22 with 84% accuracy.
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... shown to predispose to both internalizing and externalizing psychiatric disorder in childhood (Maziade et al. ... order factor accounting for their shared variance does not increase prediction of cannabis ... Effects of ADHD, conduct... more
... shown to predispose to both internalizing and externalizing psychiatric disorder in childhood (Maziade et al. ... order factor accounting for their shared variance does not increase prediction of cannabis ... Effects of ADHD, conduct disorder and gender on substance use and abuse in ...
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This investigation determined the influence of testosterone and neurobehavioral disinhibition (ND) on risk for substance use disorder (SUD). Testosterone level during puberty was hypothesized to promote social dominance associated with... more
This investigation determined the influence of testosterone and neurobehavioral disinhibition (ND) on risk for substance use disorder (SUD). Testosterone level during puberty was hypothesized to promote social dominance associated with norm-violating behavior that, in turn, predisposes individuals to use of illicit drugs and, subsequently, SUD. Using a prospective paradigm, the authors recruited 179 boys (mean age=11.62 years, SD=0.88) and followed up when participants were ages 12-14, 16, 19, and 22. Results indicated that social dominance/norm-violating behavior (SD/NVB) at age 16 mediated the association between testosterone level (ages 12-14) and SUD (age 22). In addition, SD/NVB mediated the association between ND and SUD. These findings suggest that development of SUD is influenced by androgen-dependent and neurobehavioral processes via a social motivational style characterized by SD/NVB.
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Research Interests: Psychology, Clinical Psychology, Psychiatry, Intelligence, Family, and 15 moreMedicine, Humans, Child, Substance Abuse, Achievement, Male, Addictive Behaviours, Socioeconomic Status, Parents, Problem Behavior, School Performance, Addictive Behaviors, Socioeconomic Factors, Psychiatric Status Rating Scales, and Child behavior disorders
Liabilities to complex disorders, discussed in the accompanying paper, present difficulties in measurement related to the arbitrariness of diagnostic threshold definitions and problems with discrimination between trait values, especially... more
Liabilities to complex disorders, discussed in the accompanying paper, present difficulties in measurement related to the arbitrariness of diagnostic threshold definitions and problems with discrimination between trait values, especially within the 'normal' individuals. The inability to quantitatively estimate the risk for a disorder, such as substance use disorders (SUD), is an obstacle for studying etiological (e.g. genetic) mechanisms and developing efficient prevention and treatment measures. Based on the concept of common liability to SUD, this paper delineates an application of the longitudinal family/high-risk design and item response theory to the development of a continuous index of liability. The method has been tested in both simulation study and empirical data. The approach described affords the opportunity to quantitatively estimate the risk for SUD at an early age and before any drug exposure. This method is also applicable to measuring liabilities to other complex disorders, especially those with relatively late onset.
Research Interests: Genetics, Psychology, Algorithms, Addiction, Item Response Theory, and 15 moreCausality, Medicine, Disease susceptibility, Humans, Etiology, Drug abuse, Phenotype, Liability, Risk Factors, Psychological Models, Complex Traits, Monte Carlo Method, Psychology and Cognitive Sciences, High risk, and Medical and Health Sciences
Research Interests: Adolescent, Fathers, Family history, Drug Use, Brain, and 15 moreHumans, Child, Impulse Control Disorders, Child Abuse, Male, Etiology, Adult, Cognitive Function, Age Factors, Adjustment Disorders, Disinhibition, Cognition disorders, Child Neglect, Child behavior disorders, and Medical and Health Sciences
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Additional file 1 Supplementary of Discovering Weaker Genetic Associations Guided by Known Associations, with Application to Alcoholism and Alzheimer's Disease Studies. The file has instructions of using the software and extra... more
Additional file 1 Supplementary of Discovering Weaker Genetic Associations Guided by Known Associations, with Application to Alcoholism and Alzheimer's Disease Studies. The file has instructions of using the software and extra experimental results.
Background The current understanding of the genetic basis of complex human diseases is that they are caused and affected by many common and rare genetic variants. A considerable number of the disease-associated variants have been... more
Background The current understanding of the genetic basis of complex human diseases is that they are caused and affected by many common and rare genetic variants. A considerable number of the disease-associated variants have been identified by Genome Wide Association Studies, however, they can explain only a small proportion of heritability. One of the possible reasons for the missing heritability is that many undiscovered disease-causing variants are weakly associated with the disease. This can pose serious challenges to many statistical methods, which seems to be only capable of identifying disease-associated variants with relatively stronger coefficients. Results In order to help identify weaker variants, we propose a novel statistical method, Constrained Sparse multi-locus Linear Mixed Model (CS-LMM) that aims to uncover genetic variants of weaker associations by incorporating known associations as a prior knowledge in the model. Moreover, CS-LMM accounts for polygenic effects a...
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Illicit substance use is dangerous in both acute and chronic forms, frequently resulting in lethal poisoning, addiction, and other negative consequences. Similar to research in other psychiatric conditions, whose ultimate goal is to... more
Illicit substance use is dangerous in both acute and chronic forms, frequently resulting in lethal poisoning, addiction, and other negative consequences. Similar to research in other psychiatric conditions, whose ultimate goal is to enable effective prevention and treatment, studies in substance use are focused on factors elevating the risk for the disorder. The rapid growth of the substance use problem despite the effort invested in fighting it, however, suggests the need in changing the research approach. Instead of attempting to identify risk factors, whose neutralization is often infeasible if not impossible, it may be more promising to systematically reverse the perspective to the factors enhancing the aspect of liability to disorder that shares the same dimension but is opposite to risk, that is, resistance to substance use. Resistance factors, which enable the majority of the population to remain unaffected despite the ubiquity of psychoactive substances, may be more amenable...
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Introduction FTND (Fagerstrӧm test for nicotine dependence) and TTFC (time to smoke first cigarette in the morning) are common measures of nicotine dependence (ND). However, genome-wide meta-analysis for these phenotypes has not been... more
Introduction FTND (Fagerstrӧm test for nicotine dependence) and TTFC (time to smoke first cigarette in the morning) are common measures of nicotine dependence (ND). However, genome-wide meta-analysis for these phenotypes has not been reported. Methods Genome-wide meta-analyses for FTND (N = 19,431) and TTFC (N = 18,567) phenotypes were conducted for adult smokers of European ancestry from 14 independent cohorts. Results We found that SORBS2 on 4q35 (p = 4.05 × 10−8), BG182718 on 11q22 (p = 1.02 × 10−8), and AA333164 on 14q21 (p = 4.11 × 10−9) were associated with TTFC phenotype. We attempted replication of leading candidates with independent samples (FTND, N = 7010 and TTFC, N = 10 061), however, due to limited power of the replication samples, the replication of these new loci did not reach significance. In gene-based analyses, COPB2 was found associated with FTND phenotype, and TFCP2L1, RELN, and INO80C were associated with TTFC phenotype. In pathway and network analyses, we found...
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... A common and accepted definition of resilience is Ithe property of a material that enables it to resume its original shape or ... Traits such as hardiness, competence, ego resilience, and ego strength have been used synonymously to... more
... A common and accepted definition of resilience is Ithe property of a material that enables it to resume its original shape or ... Traits such as hardiness, competence, ego resilience, and ego strength have been used synonymously to characterize individuals who have this abstruse ...
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Research Interests: Psychology, Eating Disorders, Medicine, Humans, Child, and 14 moreFemale, Nutritional Status, Body Mass Index, Risk factors, Feeding Behavior, Peer group, Longitudinal Studies, Sex Factors, Risk Factors, Social Facilitation, Sexual Maturation, Substance-Related Disorders, Psychology and Cognitive Sciences, and Medical and Health Sciences
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Research Interests: Psychology, Clinical Psychology, Psychiatry, Psychometrics, Item Response Theory, and 15 moreMedicine, Drug, Humans, Female, Male, Drug Addiction, Psychosocial, Mental Disorder, Adult, Prognosis, American Psychiatric Association, Indexation, Psychological Models, Severity of Illness Index, and Diagnostic and Statistical Manual
Research Interests: Psychology, Psychiatry, Medicine, Antisocial Personality Disorder, Cortisol, and 15 moreHumans, Child, Male, Social Environment, Risk factors, Arousal, Saliva, Psychotropic Drugs, Risk Factors, Child behavior disorders, Psychology and Cognitive Sciences, hydrocortisone, Medical and Health Sciences, Macho, and preadolescent
Variation in the risk for and severity of substance use disorders (SUD) in the population is caused by multiple organismic (genetic, biochemical, psychological) and environmental factors. Whereas drug- or drug-class-specific liability... more
Variation in the risk for and severity of substance use disorders (SUD) in the population is caused by multiple organismic (genetic, biochemical, psychological) and environmental factors. Whereas drug- or drug-class-specific liability mechanisms exist, a substantial proportion of variance in the risk is shared between specific liabilities, reflecting mechanisms that determine common liability to SUD. Data from epidemiologic, clinical, psychological, physiological, biochemical, and family and genetic studies reviewed in this paper indicate the existence of mechanisms and characteristics shared in common by liabilities to SUD related to different drugs. These mechanisms can be conceptualized as common liability to SUD, a latent trait accounting for a substantial portion of variation in SUD risk and severity and determined by all factors influencing the probability of SUD development. An accompanying paper describes an approach to the quantitative estimation of this trait.