Neuropsychosocial profiles of current and future adolescent alcohol misusers

A comprehensive account of the causes of alcohol misuse must accommodate individual differences in biology, psychology and environment, and must disentangle cause and effect. Animal models1 can demonstrate the effects of neurotoxic substances; however, they provide limited insight into the psycho-social and higher cognitive factors involved in the initiation of substance use and progression to misuse. One can search for pre-existing risk factors by testing for endophenotypic biomarkers2 in non-using relatives; however, these relatives may have personality or neural resilience factors that protect them from developing dependence3. A longitudinal study has potential to identify predictors of adolescent substance misuse, particularly if it can incorporate a wide range of potential causal factors, both proximal and distal, and their influence on numerous social, psychological and biological mechanisms4. Here we apply machine learning to a wide range of data from a large sample of adolescents (n = 692) to generate models of current and future adolescent alcohol misuse that incorporate brain structure and function, individual personality and cognitive differences, environmental factors (including gestational cigarette and alcohol exposure), life experiences, and candidate genes. These models were accurate and generalized to novel data, and point to life experiences, neurobiological differences and personality as important antecedents of binge drinking. By identifying the vulnerability factors underlying individual differences in alcohol misuse, these models shed light on the aetiology of alcohol misuse and suggest targets for prevention

Differential predictors for alcohol use in adolescents as a function of familial risk

Abstract: Traditional models of future alcohol use in adolescents have used variable-centered approaches, predicting alcohol use from a set of variables across entire samples or populations. Following the proposition that predictive factors may vary in adolescents as a function of family history, we used a two-pronged approach by first defining clusters of familial risk, followed by prediction analyses within each cluster. Thus, for the first time in adolescents, we tested whether adolescents with a family history of drug abuse exhibit a set of predictors different from adolescents without a family history. We apply this approach to a genetic risk score and individual differences in personality, cognition, behavior (risk-taking and discounting) substance use behavior at age 14, life events, and functional brain imaging, to predict scores on the alcohol use disorders identification test (AUDIT) at age 14 and 16 in a sample of adolescents (N = 1659 at baseline, N = 1327 at follow-up) from the IMAGEN cohort, a longitudinal community-based cohort of adolescents. In the absence of familial risk (n = 616), individual differences in baseline drinking, personality measures (extraversion, negative thinking), discounting behaviors, life events, and ventral striatal activation during reward anticipation were significantly associated with future AUDIT scores, while the overall model explained 22% of the variance in future AUDIT. In the presence of familial risk (n = 711), drinking behavior at age 14, personality measures (extraversion, impulsivity), behavioral risk-taking, and life events were significantly associated with future AUDIT scores, explaining 20.1% of the overall variance. Results suggest that individual differences in personality, cognition, life events, brain function, and drinking behavior contribute differentially to the prediction of future alcohol misuse. This approach may inform more individualized preventive interventions

Differential predictors for alcohol use in adolescents as a function of familial risk

Abstract: Traditional models of future alcohol use in adolescents have used variable-centered approaches, predicting alcohol use from a set of variables across entire samples or populations. Following the proposition that predictive factors may vary in adolescents as a function of family history, we used a two-pronged approach by first defining clusters of familial risk, followed by prediction analyses within each cluster. Thus, for the first time in adolescents, we tested whether adolescents with a family history of drug abuse exhibit a set of predictors different from adolescents without a family history. We apply this approach to a genetic risk score and individual differences in personality, cognition, behavior (risk-taking and discounting) substance use behavior at age 14, life events, and functional brain imaging, to predict scores on the alcohol use disorders identification test (AUDIT) at age 14 and 16 in a sample of adolescents (N = 1659 at baseline, N = 1327 at follow-up) from the IMAGEN cohort, a longitudinal community-based cohort of adolescents. In the absence of familial risk (n = 616), individual differences in baseline drinking, personality measures (extraversion, negative thinking), discounting behaviors, life events, and ventral striatal activation during reward anticipation were significantly associated with future AUDIT scores, while the overall model explained 22% of the variance in future AUDIT. In the presence of familial risk (n = 711), drinking behavior at age 14, personality measures (extraversion, impulsivity), behavioral risk-taking, and life events were significantly associated with future AUDIT scores, explaining 20.1% of the overall variance. Results suggest that individual differences in personality, cognition, life events, brain function, and drinking behavior contribute differentially to the prediction of future alcohol misuse. This approach may inform more individualized preventive interventions

Connection between parental divorce and development of youths’ personality at age 14–16

Ziel: Ziel dieser Arbeit war die Untersuchung des Zusammenhangs von Scheidung der Eltern und der Persönlichkeitsentwicklung von Jugendlichen im Alter von 14–16 Jahren. Dabei wurden die Persönlichkeitseigenschaften Ängstlichkeit, Depression, Impulsivität und Sensation Seeking betrachtet. Material und Methoden: Die Daten wurden im Rahmen der IMAGEN Studie erhoben, einer Längsschnittuntersuchung, die Jugendliche zu zwei Zeitpunkten, im Alter von 14 (T1) und 16 (T2) Jahren, untersuchte. Um der Versuchsgruppe, die eine elterliche Scheidung zwischen T1 und T2 mit- erlebt hat, eine vergleichbare Kontrollgruppe zuzuordnen, wurden die Scheidungskinder mit Nicht- Scheidungskindern gematcht. Die für diese Arbeit relevanten Persönlichkeitsfragebögen wurden mit Hilfe des T-Tests, der ANOVA und MANOVA auf die aufgestellten Hypothesen hin ausgewertet. Ergebnisse: Zur Klärung der Hauptfrage wurde herausgefunden, dass sich männliche und weibliche Jugendliche, unabhängig davon, ob sie eine elterliche Scheidung miterlebt haben, über beide Zeitpunkte, bezüglich o. g. Persönlichkeitseigenschaften, relativ ähnlich verändern. Dies lässt vermuten, dass die elterliche Scheidung nicht im Zusammenhang mit der Persönlichkeit von 14- bis 16-Jährigen steht. Es ließen sich weiterhin sekundäre Ergebnisse finden. Weibliche Jugendliche sind zu T1 signifikant ängstlicher als Männliche; zu T2 ist dieser Geschlechterunterschied als Tendenz erkennbar. Der Aspekt, dass weibliche Probanden der Versuchsgruppe sowohl zu T1 als auch zu T2 ängstlicher sind als die Probanden der Kontrollgruppe, stellt sich als Tendenz dar. Männliche und weibliche Probanden sind, wie auch Versuchs- und Kontrollgruppe, zu T1 und T2 relativ ähnlich depressiv. Weibliche Jugendliche sind zu T1 signifikant impulsiver als Männliche; zu T2 ist kein signifikanter Geschlechterunterschied erkennbar. Die Versuchsgruppe ist sowohl zu T1 als auch zu T2 signifikant impulsiver als die Kontrollgruppe. Allgemein sind Jugendliche zu T1 signifikant impulsiver als zu T2. Im Sensation-Seeking-Score erreichen Jugendliche zu T2 signifikant höhere Mittelwerte als zu T1. Ansonsten sind sich männliche und weibliche Jugendliche sowie die Probanden der Versuchs- und Kontrollgruppe in den Mittelwerten dieses Scores sowohl zu T1 als auch zu T2 sehr ähnlich. Schlussfolgerungen: Die Ergebnisse gelten für eine Selbsteinschätzung der Jugendlichen — eine objektive Verhaltenseinschätzung könnte andere Resultate liefern. Bisherige Untersuchungen, zu deren Aus- sagen die Ergebnisse dieser Arbeit kompatibel sind, können um die Erkenntnis erweitert werden, dass ein Zusammenhang zwischen elterlicher Scheidung und der Entwicklung und Veränderung o. g. Persönlichkeitseigenschaften von 14–16-jährigen Jugendlichen nicht anzunehmen ist. Weiterhin macht diese Studie darauf aufmerksam, dass Forschungsbedarf zu den Langzeiteffekten einer elterlichen Scheidung auf die Jugendlichen besteht.Aim: The study’s aim was to check the connection between parental divorce and development of youths’ personality at age 14–16. The personality traits Depression, Anxiety, Impulsivity and Sensation Seeking were considered. Methods: The data was collected in context of the IMAGEN study — a longitudinal follow-up analysis that considers youths at two points in time, at the age of 14 (T1) and 16 (T2) years. To find a control group that fits the test group, which experienced parental divorce between T1 and T2, these two groups were matched. The relevant questionnaires for personality were analyzed with the help of T-Test, ANOVA and MANOVA. Thus the presented hypothesis will be checked. Results: To sort out the main question, it had been worked out that male and female youths change concerning above mentioned personality traits, regardless of having experienced parental divorce, across both ages in a very similar way. So one can suppose that parental divorce has no relevant influence on youths’ personality at 14–16. Within the study’s context there were additional results. Female youths show at T1 significantly more Anxiety than male youths; at T2 this difference presents as a tendency. The aspect, that female test group subjects show at T1 and T2 more Anxiety than control group sub- jects, is measured as a tendency. Male and female subjects reach, as well as test and control group, nearly the same scores at T1 and T2 in Depression. Female youths are significantly more impulsive at T1 than male youths; at T2 there is no significant difference. The test group is significantly more impulsive at T1 and T2 than the control group. In general, youths are significantly more impulsive at T1 than at T2. Sensation Seeking is significantly higher at T2 than at T1. Male and female youths, as well as test and control group, show no significant difference in gender or group in Sensation Seeking at T1 and T2. Conclusions: These results are based on the youths’ self-assessment whereas an objective assessment of behaviour could supply different results. The paper expands previous investigations, with statements compatible to this paper, concerning the insight that there may be no connection between parental divorce and youths’ development of personality at age 14–16. This study points out that a lot more research is necessary, especially for longterm effects of parental divorce

Study of genetic variability in Dicrocoelium dendriticum using the random amplified polimorphic DNA

1 page.-- Contributed to: VII European Multicolloquium of Parasitology (Parma, Italia, 2-6 Sep 1996).Dicrocoelium dendriticum (Rudolphi, 1819) Looss, 1899 is a liver fluke (Trematoda, Digenea) species responsible for dicrocoeliosis in its definitive host (usually sheep and cattle), in which it causes economic losses...This study was supported by CICYT, project number AGF92-0588, and Junta de Castilla y León, project number LE 16/94.Peer reviewe

Substance Use Initiation, Particularly Alcohol, in Drug-Naive Adolescents: Possible Predictors and Consequences From a Large Cohort Naturalistic Study

International audienceIt is unclear whether deviations in brain and behavioral development, which may underpin elevated substance use during adolescence, are predispositions for or consequences of substance use initiation. Here, we examine behavioral and neuroimaging indices at early and mid-adolescence in drug-naive youths to identify possible predisposing factors for substance use initiation and its possible consequences