The longitudinal relationship between fear of movement and physical activity after cardiac hospitalization: A cross lagged panel model.

BACKGROUND: Little is known about the association between fear of movement (kinesiophobia) and objectively measured physical activity (PA), the first 12 weeks after cardiac hospitalization. PURPOSE: To assess the longitudinal association between kinesiophobia and objectively measured PA and to assess the factor structure of kinesiophobia. METHODS: We performed a longitudinal observational study. PA was continuously measured from hospital discharge to 12 weeks using the Personal Activity Monitor. The PAM measures time spent per day in PA-intensity categories: light, moderate and heavy. Kinesiophobia was assessed with the Tampa Scale for Kinesiophobia (TSK) at four time points (hospital discharge, 3, 6 and 12 weeks). The longitudinal association between PA-intensity and kinesiophobia was studied with a random intercept cross lagged panel model (RI-CLPM). A RI-CLPM estimates effects from kinesiophobia on objectively measured PA and vice versa (cross-over effects), and autoregressive effects (e.g. kinesiophobia from one occasion to the next). RESULTS: In total, 116 patients (83.6% male) with a median age of 65.5 were included in this study. On no occasion did we find an effect of kinesiophobia on PA and vice versa. Model fit for the original model was poor (X2: = 44.646 P<0.001). Best model fit was found for a model were kinesiophobia was modelled as a stable between factor (latent variable) and PA as autoregressive component (dynamic process) (X2 = 27.541 P<0.12). CONCLUSION: Kinesiophobia and objectively measured PA are not associated in the first 12 weeks after hospital discharge. This study shows that kinesiophobia remained relatively stable, 12 weeks after hospital discharge, despite fluctuations in light to moderate PA-intensity.

Why Do Bi-Factor Models Outperform Higher-Order g Factor Models? A Network Perspective.

Bi-factor models of intelligence tend to outperform higher-order g factor models statistically. The literature provides the following rivalling explanations: (i) the bi-factor model represents or closely approximates the true underlying data-generating mechanism; (ii) fit indices are biased against the higher-order g factor model in favor of the bi-factor model; (iii) a network structure underlies the data. We used a Monte Carlo simulation to investigate the validity and plausibility of each of these explanations, while controlling for their rivals. To this end, we generated 1000 sample data sets according to three competing models-a bi-factor model, a (nested) higher-order factor model, and a (non-nested) network model-with 3000 data sets in total. Parameter values were based on the confirmatory analyses of the Wechsler Scale of Intelligence IV. On each simulated data set, we (1) refitted the three models, (2) obtained the fit statistics, and (3) performed a model selection procedure. We found no evidence that the fit measures themselves are biased, but conclude that biased inferences can arise when approximate or incremental fit indices are used as if they were relative fit measures. The validity of the network explanation was established while the outcomes of our network simulations were consistent with previously reported empirical findings, indicating that the network explanation is also a plausible one. The empirical findings are inconsistent with the (also validated) hypothesis that a bi-factor model is the true model. In future model selection procedures, we recommend that researchers consider network models of intelligence, especially when a higher-order g factor model is rejected in favor of a bi-factor model.

Physician exhaustion and work engagement during the COVID-19 pandemic: A longitudinal survey into the role of resources and support interventions.

BACKGROUND: Physicians increasingly show symptoms of burnout due to the high job demands they face, posing a risk for the quality and safety of care. Job and personal resources as well as support interventions may function as protective factors when demands are high, specifically in times of crisis such as the COVID-19 pandemic. Based on the Job Demands-Resources theory, this longitudinal study investigated how monthly fluctuations in job demands and job and personal resources relate to exhaustion and work engagement and how support interventions are associated with these outcomes over time. METHODS: A longitudinal survey consisting of eight monthly measures in the period 2020-2021, completed by medical specialists and residents in the Netherlands. We used validated questionnaires to assess job demands (i.e., workload), job resources (e.g., job control), personal resources (e.g., psychological capital), emotional exhaustion, and work engagement. Additionally, we measured the use of specific support interventions (e.g., professional support). Multilevel modeling and longitudinal growth curve modeling were used to analyze the data. RESULTS: 378 medical specialists and residents were included in the analysis (response rate: 79.08%). Workload was associated with exhaustion (γ = .383, p < .001). All job resources, as well as the personal resources psychological capital and self-judgement were associated with work engagement (γs ranging from -.093 to .345, all ps < .05). Job control and psychological capital attenuated the workload-exhaustion relationship while positive feedback and peer support strengthened it (all ps < .05). The use of professional support interventions (from a mental health expert or coach) was related to higher work engagement (estimate = .168, p = .032) over time. Participation in organized supportive group meetings was associated with higher exhaustion over time (estimate = .274, p = .006). CONCLUSIONS: Job and personal resources can safeguard work engagement and mitigate the risk of emotional exhaustion. Professional support programs are associated with higher work engagement over time, whereas organized group support meetings are associated with higher exhaustion. Our results stress the importance of professional individual-level interventions to counteract a loss of work engagement in times of crisis.

Impact of kinesiophobia on initiation of cardiac rehabilitation: a prospective cohort path analysis.

OBJECTIVES: To identify factors associated with kinesiophobia (fear of movement) after cardiac hospitalisation and to assess the impact of kinesiophobia on cardiac rehabilitation (CR) initiation. DESIGN: Prospective cohort study. SETTING: Academic Medical Centre, Department of Cardiology. PARTICIPANTS: We performed a prospective cohort study in cardiac patients recruited at hospital discharge. In total, 149 patients (78.5% male) with a median age of 65 years were included, of which 82 (59%) were referred for CR. PRIMARY AND SECONDARY OUTCOME MEASURES: We assessed kinesiophobia with the Tampa Scale for Kinesiophobia (TSK). For this study, the total score was used (range 13-52). We assessed baseline factors (demographics, cardiac disease history, questionnaire data on anxiety, biopsychosocial complexity and self-efficacy) associated with kinesiophobia using linear regression with backward elimination. For linear regression, the standardised beta (ß) was reported. Prospectively, the impact of kinesiophobia on probability of CR initiation, in the first 3 months after hospital discharge (subsample referred for CR), was assessed with logistic regression. For logistic regression, the OR was reported. RESULTS: Moderate and severe levels of kinesiophobia were found in 22.8%. In the total sample, kinesiophobia was associated with cardiac anxiety (ß=0.33, 95% CI: 0.19 to 0.48), social complexity (ß=0.23, 95% CI: 0.06 to 0.39) and higher education (ß=-0.18, 95% CI: -0.34 to -0.02). In those referred for CR, kinesiophobia was negatively associated with self-efficacy (ß=-0.29, 95% CI: -0.47 to -0.12) and positively with cardiac anxiety (ß=0.43, 95% CI: 0.24 to 0.62). Kinesiophobia decreased the probability of CR initiation (OR Range13-52 points =0.92, 95% CI: 0.85 to 0.99). CONCLUSION: In patients hospitalised for cardiovascular disease, kinesiophobia is associated with cardiac anxiety, social complexity, educational level and self-efficacy. Kinesiophobia decreased the likelihood of CR initiation with 8% per point on the TSK.

Effectiveness of 'Tackle Your Tics', a brief, intensive group-based exposure therapy programme for children with tic disorders: study protocol of a randomised controlled trial.

INTRODUCTION: This paper outlines the study protocol for the Dutch Tackle Your Tics study in youth with tic disorders. Tourette syndrome and chronic tic disorders are prevalent neurodevelopmental disorders, placing considerable burden on youth and their families. Behavioural treatment is the first-line, evidence-based intervention for tic disorders, but tic reduction and availability remain relatively low. Patient associations stress the need for more accessible high-quality treatments, also focusing on improving quality of life. Therefore, the brief, intensive group-based treatment Tackle Your Tics was developed. METHODS AND ANALYSIS: Tackle Your Tics is a 4-day intensive and comprehensive group-based intervention for children and adolescents (9-17 years) with Tourette syndrome or a chronic tic disorder. The programme encompasses exposure and response prevention treatment and additional supporting components (coping strategies, relaxation exercises and parent support). To study the effectiveness of Tackle Your Tics and identify predictors/moderators at baseline, a single-blinded randomised controlled trial (n=104) is conducted, comparing Tackle Your Tics (n=52) with a waiting list condition lasting 3 months (n=52). Assessments are performed at similar time points for both groups: at baseline, after 4 weeks, and at 3 and 6 months of follow-up, on tic severity, quality of life and other psychosocial variables. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the medical ethical committee of the Amsterdam Medical Centre (METC nr NL66340.018.18, v3 June 2020). Findings will be presented on national and international conferences, peer-reviewed scientific journals, patient organisation meetings and public media. Patient representatives are fully integrated as part of the research team. If Tackle Your Tics proves to be effective, it can expand evidence-based treatment possibilities for children and adolescents with tic disorders. Identifying the psychosocial predictors/moderators for the effectiveness of this intervention can provide personalised treatment advice in the future. TRIAL REGISTRATION NUMBER: NL8052.

The Validation of the Selective Mutism Questionnaire for Use in the Dutch Population.

Selective mutism (SM) is an anxiety disorder in children/adolescents, characterized by the absence of speaking in specific social situations, mostly at school. The selective mutism questionnaire (SMQ) is a parent report, internationally used to assess SM symptomatology and treatment outcomes. Since no assessment instrument for SM was available in the Netherlands, our aim was to investigate the psychometric properties of the Dutch translation of the SMQ, through reliability, confirmatory factor, and ROC analyses conducted on data obtained in 303 children (ages 3-17 years; clinical SM group n = 106, control group n = 197). The SMQ turned out to be highly reliable (α = 0.96 in the combined sample; 0.83 within the clinical group) and followed the expected factor structure. We conclude that the Dutch version of the SMQ is a reliable and valid tool both as a screening and clinical instrument to assess SM in Dutch speaking children.

Unmet support needs in donor sperm treatment: consequences for parents and their donor-children.

RESEARCH QUESTION: Are unmet needs for psychosocial counselling, peer support and friends/family support in parents directly and/or indirectly related to the mental health of parents and their donor-children? DESIGN: A cross-sectional sample of 214 parents participated in this quantitative study via an online questionnaire. The sample comprised mothers and fathers in a heterosexual relationship (n = 85), mothers in a lesbian relationship (n = 67) and single mothers (n = 62). Parents were recruited via three Dutch fertility clinics and four network organizations. Unmet support needs were measured with an adapted version of the Unmet Needs for Parenting Support questionnaire, changing the original items into items about donor conception. The items were derived from a qualitative study and checked by experts in donor conception. The parents' mental health was measured with the Adult Self Report and the donor-children's mental health with the Child Behaviour Checklist. A multigroup mediation analysis was conducted to explore relationships between parents' unmet support needs and their child's mental health, with the parents' mental health as a possible mediator. RESULTS: There were no direct relations between parents' unmet support needs and the mental health of donor-children. Unmet needs for psychosocial counselling, peer support and friends/family support for parents and children's mental health were indirectly related through the mental health of the parents: 0.074 (CI 95%  = 0.013-0.136; P = 0.017), 0.085 (CI 95% = 0.018-0.151; P = 0.036) and 0.063 (CI 95% = 0.019-0.106; P = 0.013), respectively. CONCLUSIONS: We recommend that fertility clinics, network organizations and authorities for infertility counsellors make their support available to parents for extended periods after their treatment. Further qualitative studies are necessary to assess how to relieve unmet support needs during donor sperm treatment.

How to Compare Psychometric Factor and Network Models.

In memory of Dr. Dennis John McFarland, who passed away recently, our objective is to continue his efforts to compare psychometric networks and latent variable models statistically. We do so by providing a commentary on his latest work, which he encouraged us to write, shortly before his death. We first discuss the statistical procedure McFarland used, which involved structural equation modeling (SEM) in standard SEM software. Next, we evaluate the penta-factor model of intelligence. We conclude that (1) standard SEM software is not suitable for the comparison of psychometric networks with latent variable models, and (2) the penta-factor model of intelligence is only of limited value, as it is nonidentified. We conclude with a reanalysis of the Wechlser Adult Intelligence Scale data McFarland discussed and illustrate how network and latent variable models can be compared using the recently developed R package Psychonetrics. Of substantive theoretical interest, the results support a network interpretation of general intelligence. A novel empirical finding is that networks of intelligence replicate over standardization samples.

Neural Correlates of Adolescent Irritability and Its Comorbidity With Psychiatric Disorders.

OBJECTIVE: Irritable mood, a common and impairing symptom in psychopathology, has been proposed to underlie the developmental link between oppositional problems in youth and depression in adulthood. We examined the neural correlates of adolescent irritability in IMAGEN, a sample of 2,024 14-year-old adolescents from 5 European countries. METHOD: The Development and Well-Being Assessment (DAWBA) was used to assess attention-deficit/hyperactivity disorder, major depressive disorder, oppositional defiant disorder, and generalized anxiety disorder. Three items from the DAWBA, selected as close matches to the Affective Reactivity Index, were used to assess irritability. Structural magnetic resonance imaging was examined using whole-brain voxel-based morphometry analysis, and functional magnetic resonance imaging was examined during a stop signal task of inhibitory control. Imaging data were included in structural equation models to examine the direct and indirect associations between irritable mood and comorbid DSM diagnoses. RESULTS: Whole-brain voxelwise analysis showed that adolescent irritable mood was associated with less gray matter volume and less neural activation underlying inhibitory control in frontal and temporal cortical areas (cluster-correction at p < .05). Structural equation models suggested that part of the observed smaller gray matter volume was exclusively driven by irritability separate from direct relationships between generalized anxiety disorder (or attention-deficit/hyperactivity disorder, major depressive disorder, or oppositional defiant disorder) and gray matter volume. CONCLUSION: This study identifies adolescent irritability as an independent construct and points to a neurobiological correlate to irritability that is an important contributing feature to many psychopathological disorders.

The moderating role of SES on genetic differences in educational achievement in the Netherlands.

Parental socioeconomic status (SES) is a strong predictor of children's educational achievement (EA), with an increasing effect throughout development. Inequality in educational outcomes between children from different SES backgrounds exists in all Western countries. It has been proposed that a cause of this inequality lies in the interplay between genetic effects and SES on EA, which might depend on society and the equality of the education system. This study adopted two approaches, a classical twin design and polygenic score (PGS) approach, to address the effect of parental SES on EA in a large sample of 12-year-old Dutch twin pairs (2479 MZ and 4450 DZ twin pairs with PGSs for educational attainment available in 2335 children) from the Netherlands Twin Register (NTR). The findings of this study indicated that average EA increased with increasing parental SES. The difference in EA between boys and girls became smaller in the higher SES groups. The classical twin design analyses based on genetic covariance structure modeling pointed to lower genetic, environmental, and thus phenotypic variation in EA at higher SES. Independent from a child's PGS, parental SES predicted EA. However, the strength of the association between PGS and EA did not depend on parental SES. In a within-family design, the twin with a higher PGS scored higher on EA than the co-twin, demonstrating that the effect of the PGS on EA was at least partly independent from parental SES. To conclude, EA depended on SES both directly and indirectly, and SES moderated the additive genetic and environmental components of EA. Adding information from PGS, in addition to parental SES, improved the prediction of children's EA.

Are Socially Anxious Children Poor or Advanced Mindreaders?

Why are some children more socially anxious than others? One theory holds that socially anxious children are poor mindreaders, which hampers their social interactions; another that socially anxious children are advanced mindreaders leading to heightened self-consciousness in social situations. To test these theories simultaneously, this study (N = 105, ages 8-12) assessed children's mindreading (accuracy in detecting mental states from the eye region), self-consciousness (indexed as physiological blushing during public performance), and social anxiety levels. Results support both theories, showing a quadratic relation between mindreading and social anxiety. Low mindreading was related to clinical levels of social anxiety. High mindreading was related to subclinical levels of social anxiety through blushing. Our findings suggest two social-cognitive pathways to heightened social anxiety.

Low Smoking Exposure, the Adolescent Brain, and the Modulating Role of CHRNA5 Polymorphisms.

BACKGROUND: Studying the neural consequences of tobacco smoking during adolescence, including those associated with early light use, may help expose the mechanisms that underlie the transition from initial use to nicotine dependence in adulthood. However, only a few studies in adolescents exist, and they include small samples. In addition, the neural mechanism, if one exists, that links nicotinic receptor genes to smoking behavior in adolescents is still unknown. METHODS: Structural and diffusion tensor magnetic resonance imaging data were acquired from a large sample of 14-year-old adolescents who completed an extensive battery of neuropsychological, clinical, personality, and drug-use assessments. Additional assessments were conducted at 16 years of age. RESULTS: Exposure to smoking in adolescents, even at low doses, is linked to volume changes in the ventromedial prefrontal cortex and to altered neuronal connectivity in the corpus callosum. The longitudinal analyses strongly suggest that these effects are not preexisting conditions in those who progress to smoking. There was a genetic contribution wherein the volume reduction effects were magnified in smokers who were carriers of the high-risk genotype of the alpha 5 nicotinic receptor subunit gene, rs16969968. CONCLUSIONS: These findings give insight into a mechanism involving genes, brain structure, and connectivity underlying why some adolescents find nicotine especially addictive.

Testing Syndromes of Psychopathology in Parent and Youth Ratings Across Societies.

As societies become increasingly diverse, mental health professionals need instruments for assessing emotional, behavioral, and social problems in terms of constructs that are supported within and across societies. Building on decades of research findings, multisample alignment confirmatory factor analyses tested an empirically based 8-syndrome model on parent ratings across 30 societies and youth self-ratings across 19 societies. The Child Behavior Checklist for Ages 6-18 and Youth Self-Report for Ages 11-18 were used to measure syndromes descriptively designated as Anxious/Depressed, Withdrawn/Depressed, Somatic Complaints, Social Problems, Thought Problems, Attention Problems, Rule-Breaking Behavior, and Aggressive Behavior. For both parent ratings (N = 61,703) and self-ratings (N = 29,486), results supported aggregation of problem items into 8 first-order syndromes for all societies (configural invariance), plus the invariance of item loadings (metric invariance) across the majority of societies. Supported across many societies in both parent and self-ratings, the 8 syndromes offer a parsimonious phenotypic taxonomy with clearly operationalized assessment criteria. Mental health professionals in many societies can use the 8 syndromes to assess children and youths for clinical, training, and scientific purposes.

The genetic and environmental architecture of substance use development from early adolescence into young adulthood: a longitudinal twin study of comorbidity of alcohol, tobacco and illicit drug use.

AIMS: To investigate how use of alcohol, illicit drugs and tobacco come from substance-specific pathways and from pathways general to all three substances through adolescent development. DESIGN: Analysis of population-based survey. Adolescent twins reported alcohol use (AU), tobacco use (TU) and illicit drug use (IDU) in three waves (2006, 2008, 2010). Restructuring data by age allowed for variance decomposition into age- and substance-specific and common genetic and environmental variance components. SETTING: Norway. PARTICIPANTS: Seven national twin birth cohorts from 1988 to 1994, totalling 1483 pairs (558 monozygotic; 925 dizygotic, same and opposite sex). MEASUREMENTS: Six-point Likert scores of AU, TU and IDU on items from the Monitoring the Future Study. FINDINGS: Substance use was found to be highly heritable; a2  = 0.73 [95% confidence interval (CI) = 0.61-0.94] for AU, a2  = 0.36 (CI = 0.18-0.52); d2  = 0.49 (95% CI = 0.29-0.62) for IDU and a2  = 0.46 (95% CI = 0.23-0.54); d2  = 0.05 (95% CI = 0.00-0.07) for TU during the whole adolescence period. General substance use (GSU) was also highly heritable at each age and averaged a2  = 0.57 (95% CI = 0.48-0.66). There was a high genetic carry-over from earlier age to later age. Genetic effects on GSU at ages 12-14 years were still detectable 4 years later. New substance (general and specific)-genetic effects also appeared. IDU demonstrated significant non-additive genetic effects (ages 12-14 years). Shared environment had a small impact on AU only. There was almost no non-shared environmental carry-over from age to age, the effect probably due partly to reliability deficiency. Common genetic effects among substance and substance-specific genetic effects were observed at each age-period. CONCLUSIONS: Among Norwegian adolescents, there appear to be strong genetic effects on both substance-specific and comorbid use of alcohol, illicit drugs and tobacco; individual differences in alcohol use can be explained partially by family background.

Brain Regions Related to Impulsivity Mediate the Effects of Early Adversity on Antisocial Behavior.

BACKGROUND: Individual differences in impulsivity and early adversity are known to be strong predictors of adolescent antisocial behavior. However, the neurobiological bases of impulsivity and their relation to antisocial behavior and adversity are poorly understood. METHODS: Impulsivity was estimated with a temporal discounting task. Voxel-based morphometry was used to determine the brain structural correlates of temporal discounting in a large cohort (n = 1830) of 14- to 15-year-old children. Mediation analysis was then used to determine whether the volumes of brain regions associated with temporal discounting mediate the relation between adverse life events (e.g., family conflict, serious accidents) and antisocial behaviors (e.g., precocious sexual activity, bullying, illicit substance use). RESULTS: Greater temporal discounting (more impulsivity) was associated with 1) lower volume in frontomedial cortex and bilateral insula and 2) greater volume in a subcortical region encompassing the ventral striatum, hypothalamus and anterior thalamus. The volume ratio between these cortical and subcortical regions was found to partially mediate the relation between adverse life events and antisocial behavior. CONCLUSIONS: Temporal discounting is related to regions of the brain involved in reward processing and interoception. The results support a developmental imbalance model of impulsivity and are consistent with the idea that negative environmental factors can alter the developing brain in ways that promote antisocial behavior.

Network Models for Cognitive Development and Intelligence.

Cronbach's (1957) famous division of scientific psychology into two disciplines is still apparent for the fields of cognition (general mechanisms) and intelligence (dimensionality of individual differences). The welcome integration of the two fields requires the construction of mechanistic models of cognition and cognitive development that explain key phenomena in individual differences research. In this paper, we argue that network modeling is a promising approach to integrate the processes of cognitive development and (developing) intelligence into one unified theory. Network models are defined mathematically, describe mechanisms on the level of the individual, and are able to explain positive correlations among intelligence subtest scores-the empirical basis for the well-known g-factor-as well as more complex factorial structures. Links between network modeling, factor modeling, and item response theory allow for a common metric, encompassing both discrete and continuous characteristics, for cognitive development and intelligence.

No Evidence of Causal Effects of Blood Pressure on Cognition in the Population at Large.

The large body of literature on the association between blood pressure (BP) and cognitive functioning has yielded mixed results, possibly due to the presence of non-linear effects across age, or because BP affects specific brain areas differently, impacting more on some cognitive skills than on others. If a robust association was detected among BP and specific cognitive tasks, the causal nature of reported associations between BP and cognition could be investigated in twin data, which allow a test of alternative explanations, including genetic pleiotropy. The present study first examines the association between BP and cognition in a sample of 1,140 participants with an age range between 10 and 86 years. Linear and quadratic effects of systolic BP (SBP) and diastolic BP (DBP) on cognitive functioning were examined for 17 tests across five functions. Associations were corrected for effects of sex and linear and quadratic effects of age. Second, to test a causal model, data from 123 monozygotic (MZ) twin pairs were analyzed to test whether cognitive functioning of the twins with the higher BP was different from that of the co-twins with lower BP. Associations between BP and cognitive functioning were absent for the majority of the cognitive tests, with the exception of a lower speed of emotion identification and verbal reasoning in subjects with high diastolic BP. In the MZ twin pair analyses, no effects of BP on cognition were found. We conclude that in the population at large, BP level is not associated with cognitive functioning in a clinically meaningful way.

Genetic imaging consortium for addiction medicine: From neuroimaging to genes.

Since the sample size of a typical neuroimaging study lacks sufficient statistical power to explore unknown genomic associations with brain phenotypes, several international genetic imaging consortia have been organized in recent years to pool data across sites. The challenges and achievements of these consortia are considered here with the goal of leveraging these resources to study addiction. The authors of this review have joined together to form an Addiction working group within the framework of the ENIGMA project, a meta-analytic approach to multisite genetic imaging data. Collectively, the Addiction working group possesses neuroimaging and genomic data obtained from over 10,000 subjects. The deadline for contributing data to the first round of analyses occurred at the beginning of May 2015. The studies performed on this data should significantly impact our understanding of the genetic and neurobiological basis of addiction.

The Computerized Neurocognitive Battery: Validation, aging effects, and heritability across cognitive domains.

OBJECTIVE: The Computerized Neurocognitive Battery (CNB) enables efficient neurocognitive assessment. The authors aimed to (a) estimate validity and reliability of the battery's Dutch translation, (b) investigate effects of age across cognitive domains, and (c) estimate heritability of the CNB tests. METHOD: A population-representative sample of 1,140 participants (aged 10-86), mainly twin-families, was tested on the CNB, providing measures of speed and accuracy in 14 cognitive domains. In a subsample (246 subjects aged 14-22), IQ data (Wechsler Intelligence Scale for Adults; WAIS) were available. Validity and reliability were assessed by Cronbach's alpha, comparisons of scores between Dutch and U.S. samples, and investigation of how a CNB-based common factor compared to a WAIS-based general factor of intelligence (g). Linear and nonlinear age dependencies covering the life span were modeled through regression. Heritability was estimated from twin data and from entire pedigree data. RESULTS: Internal consistency of all tests was moderate to high (median = 0.86). Effects of gender, age, and education on cognitive performance closely resembled U.S. SAMPLES: The CNB-based common factor was completely captured by the WAIS-based g. Some domains, like nonverbal reasoning accuracy, peaked in young adulthood and showed steady decline. Other domains, like language reasoning accuracy, peaked in middle adulthood and were spared decline. CNB-test heritabilities were moderate (median h2 = 31%). Heritability of the CNB common factor was 70%, similar to the WAIS-based g-factor. CONCLUSION: The CNB can be used to assess specific neurocognitive performance, as well as to obtain a reliable proxy of general intelligence. Effects of aging and heritability differed across cognitive domains.

Cannabis use in early adolescence: Evidence of amygdala hypersensitivity to signals of threat.

Cannabis use in adolescence may be characterized by differences in the neural basis of affective processing. In this study, we used an fMRI affective face processing task to compare a large group (n=70) of 14-year olds with a history of cannabis use to a group (n=70) of never-using controls matched on numerous characteristics including IQ, SES, alcohol and cigarette use. The task contained short movies displaying angry and neutral faces. Results indicated that cannabis users had greater reactivity in the bilateral amygdalae to angry faces than neutral faces, an effect that was not observed in their abstinent peers. In contrast, activity levels in the cannabis users in cortical areas including the right temporal-parietal junction and bilateral dorsolateral prefrontal cortex did not discriminate between the two face conditions, but did differ in controls. Results did not change after excluding subjects with any psychiatric symptomology. Given the high density of cannabinoid receptors in the amygdala, our findings suggest cannabis use in early adolescence is associated with hypersensitivity to signals of threat. Hypersensitivity to negative affect in adolescence may place the subject at-risk for mood disorders in adulthood.