Cascades From Early Adolescent Impulsivity to Late Adolescent Antisocial Personality Disorder and Alcohol Use Disorder.

PURPOSE: The behavioral disinhibition model (BDM) posits that a liability toward impulsivity evident by early adolescence underlies the coemergence of antisocial behavior and alcohol use (i.e., problem behaviors) in early-adolescence to mid-adolescence, but that the subsequent development of these problem behaviors (rather than impulsivity itself) predicts the emergence of antisocial personality disorder (APD) and alcohol use disorder (AUD) in late adolescence. The present study was designed to test these predictions of the BDM from early to late adolescence. METHODS: We used five-year longitudinal self-report data from the Philadelphia Trajectory Study that was collected from 2006-2012. Mediational analyses were performed using the Random Intercept Cross-lagged Panel Model, which enables the detection of within-person predictions of changes in problem behaviors during adolescence. The sample was ethnically and socioeconomically diverse, including 364 urban US community youth (at baseline: Mage = 13.51(.95); 49.1% female). RESULTS: Consistent with the BDM, mediational analyses revealed that changes in early adolescent impulsivity predicted late adolescent APD and AUD criteria, mediated by changes in mid-adolescent alcohol use and conduct problems. DISCUSSION: Interventions targeting impulsivity in early adolescence could potentially halt the cascading chain of events leading to both late adolescent APD and AUD by decelerating growth in antisocial behavior and alcohol use during early-adolescence to mid-adolescence. From mid-adolescence to late-adolescence, the consequences of early impulsivity, especially involvement in antisocial behaviors, become a more relevant predictor of both APD and AUD rather than impulsivity itself.

Studies in Neotropical Pseudophyllinae: A new genus of Cocconotini from the Colombian Andes and new subfamily assignment of the Dominican genus Anacaona (Tettigoniidae: Pseudophyllinae: Cocconotini).

Acuscercus eudaldoleondiazi n. gen et n. sp. from the Eastern slopes of the Colombian Andes is described, a typical long-winged member of the tribe Cocconotini, distinguished by peculiar morphology of male cerci. On the other hand, the Dominican genus Anacaona is moved from Cocconotini to the tribe Copiphorini (Conocephalinae). The status and tribal boundaries of Cocconotini and Eucocconotini are briefly discussed.

Working Memory Development and Motor Vehicle Crashes in Young Drivers.

Importance: Adolescent drivers have the highest rate of motor vehicle crashes, and among equally novice drivers, crash risk is inversely age graded. Working memory (WM), crucial to driving hazard awareness, is also age graded, with ongoing development into late adolescence. Variability in WM capacity and growth trajectory positions WM as a candidate crash risk factor for study, clinical screening, and possible preventative intervention. Objective: To test the association between crashes and differential WM development. Design, Setting, and Participants: This prospective cohort study used data from a longitudinal cohort of 118 community youth in Philadelphia, Pennsylvania. Working memory and other risk factors were measured annually from age 11 to 13 years (prelicensure, in 2005) to 14 to 16 years (in 2009), and again at 18 to 20 years (in 2013). In 2015, a follow-up survey of driving experience identified 84 participants who had started driving. Latent growth curve modeling was used to examine the association between variability in the baseline (intercept) and developmental trajectory (slope) of WM and the crash outcome. Main Outcomes and Measures: Self-reported crashes were the primary outcome. Variability in the relative growth of WM development along with traits and behaviors associated with risky driving were assessed. Results: Of 84 participants (39 [46%] male; mean [SD] age, 20.46 [1.09] years), 25 (29.8%) reported they had been involved in at least 1 crash. Controlling for other crash risk factors, the model indicated that variation in the linear slope of WM growth was inversely associated with reporting a crash (b = -6.41; SE = 2.64; P = .02). Crashes were also associated with reckless driving behavior (b = 0.40; SE = 0.18; P = .03). Variation in the intercept of WM was not associated with crashes (b = -0.245; SE = 0.67; P = .72). Conclusions and Relevance: The results suggest that a relatively slower WM growth trajectory is associated with young driver crashes. Routine assessment of WM across adolescence may help to identify at-risk teen drivers and opportunities for providing adaptive interventions (eg, driving aids or training) that can address limitations in WM-related skills that are critical for safe driving.

Disentangling longitudinal relations between youth cannabis use, peer cannabis use, and conduct problems: developmental cascading links to cannabis use disorder.

AIMS: To determine whether cannabis use during adolescence can increase risk not only for cannabis use disorder (CUD) but also for conduct problems, potentially mediated by exposure to peers who use cannabis. DESIGN, SETTING, PARTICIPANTS: Longitudinal study analyzing four waves of longitudinal data from 364 racially and socio-economically diverse, urban, US community youth (at baseline: Mage  = 13.51 (0.95); 49.1% female). MEASUREMENTS: Self-reports of cannabis use, conduct problems, proportion of peers using cannabis and CUD criteria at the final wave were analyzed using a method sensitive to changes over development, the random-intercept cross-lagged panel model. FINDINGS: Change in cannabis use did not predict changes in conduct problems or peer cannabis use over time, controlling for gender, race-ethnicity and socio-economic status. Instead, increases in conduct problems predicted increases in cannabis use and ultimately CUD, with some of the effect mediated by increases in the prevalence of peer cannabis use [ß = 0.12, 95% confidence interval (CI) = 0.07, 0.20]. Additionally, affiliation with peers who used cannabis predicted subsequent CUD via increased personal cannabis use (ß = 0.08, 95% CI = 0.04, 0.14). Significant within-person betas for the cross-lagged effects ranged between 0.20 and 0.27. CONCLUSIONS: Cannabis use in adolescence does not appear to lead to greater conduct problems or association with cannabis-using peers apart from pre-existing conduct problems. Instead, adolescents who (1) increasingly affiliate with cannabis-using peers or (2) have increasing levels of conduct problems are more likely to use cannabis, and this cascading chain of events appears to predict cannabis use disorder in emerging adulthood.

Modeling Trajectories of Sensation Seeking and Impulsivity Dimensions from Early to Late Adolescence: Universal Trends or Distinct Sub-groups?

Developmental imbalance models attribute the rise in risk-taking during adolescence to a universal imbalance between rising reward sensitivity and lagging cognitive control. This study tested predictions of an alternate Lifespan Wisdom Model that distinguishes between exploratory/adaptive (e.g., sensation seeking) and maladaptive (e.g., acting-without-thinking, delay discounting) risk-taking propensities and attributes the latter to a sub-set of youth with weak cognitive control. Latent trajectory modeling of six waves of data from 387 adolescents (52% females; spanning average ages of 11-18 years) revealed distinct sub-groups with heterogeneous trajectory patterns for acting-without-thinking and delay-discounting. Only those trajectory groups with weak cognitive control, characterized as "high-increasing" acting-without thinking and "high-stable" delay discounting were predictive of a maladaptive risk-taking outcome, namely substance use disorder. Sensation seeking demonstrated a universal peak, but high levels of sensation seeking were not associated with weakness in cognitive control and were unrelated to substance use disorder, controlling for impulsivity. The findings suggest that maladaptive risk-taking characterized by weak cognitive control over reward-driven impulses is a phenomenon limited to only a sub-set of youth.

Turning 1 Year of Age in a Low Socioeconomic Environment: A Portrait of Disadvantage.

In the United States today, 16 million children are growing up poor. Few studies report multiple environmental factors associated with poverty during the first year of life and effects on infant development. OBJECTIVES: To evaluate maternal, home, and neighborhood environment of low and higher socioeconomic status (SES) infants from birth to 1 year and to evaluate the impact of SES and environment on infant developmental outcome at 1 year. METHODS: Low (n = 30) and higher SES (n = 30) African-American mothers and their healthy term gestation female infants were prospectively compared for environmental characteristics and infant developmental outcome. Wechsler Adult Intelligence Scale-IV (WAIS-IV); Beck Depression Inventory; Perceived Stress Scale; Parenting Stress Index-Fourth Edition (PSI-4); Social Support Scale; Home Observation Measurement of the Environment (HOME); Household Food Insecurity (HFI); Concentrated Neighborhood Disadvantage (CND). Bayley Scales of Infant Development Third Edition (BSID-III); Preschool Language Scale (PLS-5). RESULTS: Environmental risk was greater for low compared with higher SES: lower WAIS-IV (p < .001); higher PSI-4 total (p = .003); lower HOME total and 3 subscales (p < .002); higher HFI (p = .012); and higher CND (p = .027). Low SES infant outcomes differed from higher SES: lower BSID-III Cognitive Composite (p = .005), PLS-5 Total Language (p ≤ .017), and Auditory Comprehension (p ≤ .008). In regressions, after controlling for SES, effects of environmental factors were not found. CONCLUSION: By age 1, low SES infants had been exposed to greater environmental disadvantage and already exhibited poorer developmental functioning than higher SES infants. These findings suggest that support for families and children from impoverished circumstances cannot begin too early.

Working memory ability and early drug use progression as predictors of adolescent substance use disorders.

AIMS: To test a neurobehavioral model of adolescent substance use disorder (SUD) resulting from an imbalance between a hyperactive reward motivation system and a hypoactive executive control system. Specifically, we tested (1) if early weakness in working memory (WM) and associated imbalance indicators of acting-without-thinking (AWT) and delay discounting (DD) predict SUD in late adolescence and (2) if early drug use progression mediates this relation. DESIGN: Five waves of longitudinal data collected annually from 2005 to 2010, with a final follow-up in 2012. SETTING AND PARTICIPANTS: Sample of 387 community adolescents (baseline ages 11-13 years) recruited from the Philadelphia, PA, USA area. MEASUREMENTS: WM was assessed at baseline using four different computerized tasks. AWT and DD were assessed at baseline using self-reports. Early drug use patterns were modeled using annual self-reports of recent drug use across the first four waves. Final outcome of SUD was assessed at last wave using self-reports matched to the DSM-5 criteria for three commonly used substances: alcohol, marijuana and tobacco. FINDINGS: Weakness in WM at baseline, associated with neurobehavioral imbalance indicators of AWT, B (SE) = -0.06 (0.02), P < 0.01 and DD, B (SE) = -7.30 (1.93), P < 0.01, was a significant predictor of SUD at final follow-up. WM predicted SUD both independent of early drug use, B (SE) = 0.08 (0.03), P < 0.05, and as mediated by early drug use progression, B (SE) = -0.06 (0.02), P < 0.01. CONCLUSIONS: Adolescents with weak working memory have less control over impulsive urges, placing them at risk for later substance use disorder with some of the effects mediated by early drug use progression.

Effect of socioeconomic status disparity on child language and neural outcome: how early is early?

It is not news that poverty adversely affects child outcome. The literature is replete with reports of deleterious effects on developmental outcome, cognitive function, and school performance in children and youth. Causative factors include poor nutrition, exposure to toxins, inadequate parenting, lack of cognitive stimulation, unstable social support, genetics, and toxic environments. Less is known regarding how early in life adverse effects may be detected. This review proposes to elucidate "how early is early" through discussion of seminal articles related to the effect of socioeconomic status on language outcome and a discussion of the emerging literature on effects of socioeconomic status disparity on brain structure in very young children. Given the young ages at which such outcomes are detected, the critical need for early targeted interventions for our youngest is underscored. Further, the fiscal reasonableness of initiating quality interventions supports these initiatives. As early life adversity produces lasting and deleterious effects on developmental outcome and brain structure, increased focus on programs and policies directed to reducing the impact of socioeconomic disparities is essential.

Effect of socioeconomic status (SES) disparity on neural development in female African-American infants at age 1 month.

There is increasing interest in both the cumulative and long-term impact of early life adversity on brain structure and function, especially as the brain is both highly vulnerable and highly adaptive during childhood. Relationships between SES and neural development have been shown in children older than age 2 years. Less is known regarding the impact of SES on neural development in children before age 2. This paper examines the effect of SES, indexed by income-to-needs (ITN) and maternal education, on cortical gray, deep gray, and white matter volumes in term, healthy, appropriate for gestational age, African-American, female infants. At 5 weeks postnatal age, unsedated infants underwent MRI (3.0T Siemens Verio scanner, 32-channel head coil). Images were segmented based on a locally constructed template. Utilizing hierarchical linear regression, SES effects on MRI volumes were examined. In this cohort of healthy African-American female infants of varying SES, lower SES was associated with smaller cortical gray and deep gray matter volumes. These SES effects on neural outcome at such a young age build on similar studies of older children, suggesting that the biological embedding of adversity may occur very early in development.

Relation of Childhood Home Environment to Cortical Thickness in Late Adolescence: Specificity of Experience and Timing.

What are the long-term effects of childhood experience on brain development? Research with animals shows that the quality of environmental stimulation and parental nurturance both play important roles in shaping lifelong brain structure and function. Human research has so far been limited to the effects of abnormal experience and pathological development. Using a unique longitudinal dataset of in-home measures of childhood experience at ages 4 and 8 and MRI acquired in late adolescence, we were able to relate normal variation in childhood experience to later life cortical thickness. Environmental stimulation at age 4 predicted cortical thickness in a set of automatically derived regions in temporal and prefrontal cortex. In contrast, age 8 experience was not predictive. Parental nurturance was not predictive at either age. This work reveals an association between childhood experience and later brain structure that is specific relative to aspects of experience, regions of brain, and timing.

Socioeconomic (SES) differences in language are evident in female infants at 7months of age.

BACKGROUND: Language skills, strongly linked to academic success, are known to differ by socioeconomic status (SES), with lower SES individuals performing less well than higher SES. AIMS: To examine the effect of SES on infant language at 7months of age and the relationship between maternal vocabulary skills and infant language function. To determine if the relationships between SES and infant language are mediated by maternal vocabulary skills. STUDY DESIGN: Longitudinal follow-up of healthy term female African American infants born to mothers in two SES groups: Low SES (income-to-needs≤1, no education beyond high school) and Higher SES (Income-to-Needs >1, at least a high school diploma). SUBJECTS: 54 infants tested at 7months of age; 54 mothers tested at infant age 7months. OUTCOME MEASURES: Preschool Language Scale-5 (PLS-5), Vocabulary and Matrix Reasoning subtests of the Wechsler Adult Intelligence Scale-IV. RESULTS: Low SES infants (n=29) performed less well than Higher SES (n=25) on PLS-5 Total Language, Auditory Comprehension, and Expressive Communication (p≤0.012). Maternal Vocabulary subtest scores were lower in Low SES than Higher SES (p=0.002), but not related to infant PLS Language scores (p≥0.17). Maternal vocabulary did not mediate the relationship between SES and infant language skills at age 7months. CONCLUSIONS: In this single sex and race cohort of healthy, term, female infants, lower SES exerted negative effects on infant language by 7months of age. While maternal vocabulary scores showed no relation with infant language skills at 7months, continued study of the relations between SES, infant outcomes and maternal characteristics is needed to determine how low SES conditions impact early language. These findings underscore the importance of early interventions, as well as policies designed to improve socioeconomic conditions for infants and families.

Stronger Working Memory Reduces Sexual Risk Taking in Adolescents, Even After Controlling for Parental Influences.

This study examined the prospective influence of adolescent working memory (WM) on changes in impulsivity and sexual risk taking and assessed whether this relation could be explained by confounding effects of parental influences. Data from 360 community adolescents (Mage  = 13.5 ± 0.95 years; 52% female; 56% non-Hispanic White; low-mid socioeconomic status (SES); recruited from Philadelphia area in 2004-2005) were analyzed using structural equation modeling to predict changes in impulsivity and sexual risk taking over a 2-year follow-up, using baseline assessments of WM, parental monitoring, parental involvement, and SES. Stronger WM predicted reduced involvement in sexual risk taking at follow-up, effects channeled through changes in impulsivity dimensions of "acting without thinking" and "inability to delay gratification." Parental variables had a protective influence on adolescent impulsivity and risk involvement, but the effects of WM operated independently of parental influences.

Experimentation versus progression in adolescent drug use: A test of an emerging neurobehavioral imbalance model.

Based on an emerging neuroscience model of addiction, this study examines how an imbalance between two neurobehavioral systems (reward motivation and executive control) can distinguish between early adolescent progressive drug use and mere experimentation with drugs. Data from four annual assessments of a community cohort (N = 382) of 11- to 13-year-olds were analyzed to model heterogeneity in patterns of early drug use. Baseline assessments of working memory (an indicator of the functional integrity of the executive control system) and three dimensions of impulsivity (characterizing the balance between reward seeking and executive control systems) were used to predict heterogeneous latent classes of drug use trajectories from early to midadolescence. Findings revealed that an imbalance resulting from weak executive control and heightened reward seeking was predictive of early progression in drug use, while heightened reward seeking balanced by a strong control system was predictive of occasional experimentation only. Implications of these results are discussed in terms of preventive interventions that can target underlying weaknesses in executive control during younger years, and potentially enable at-risk adolescents to exercise greater self-restraint in the context of rewarding drug-related cues.

Mapping the trajectory of socioeconomic disparity in working memory: parental and neighborhood factors.

Working memory (WM) is positively correlated with socioeconomic status (SES). It is not clear, however, if SES predicts the rate of WM development over time or whether SES effects are specific to family rather than neighborhood SES. A community sample of children (n = 316) enrolled between ages 10 and 13 completed four annual assessments of WM. Lower parental education, but not neighborhood disadvantage, was associated with worse WM performance. Neither measure of SES was associated with the rate of developmental change. Consequently, the SES disparity in WM is not a developmental lag that narrows or an accumulating effect that becomes more pronounced. Rather, the relation between family SES and WM originates earlier in childhood and is stable through adolescence.

The effect of socioeconomic status on the language outcome of preterm infants at toddler age.

BACKGROUND: Independently, both prematurity and low socioeconomic status (SES) compromise language outcome but less is known regarding the effects of low SES on outcome of prior preterm infants at toddler age. AIM: To assess SES effects on the language outcome of prior preterm infants at toddler age. STUDY DESIGN: Retrospective chart review of infants born at ≤32 weeks, matched for gestational age (GA), birth weight (BW), chronic lung disease (CLD), periventricular leukomalacia (PVL), right and left intraventricular hemorrhage (IVH-R, L), and age at Bayley Scales of Infant Development III (BSID-III) testing. SUBJECTS: Using insurance status as a proxy for SES, 65 children with private insurance (P-Ins) were matched with 65 children with Medicaid-type insurance (M-Ins). OUTCOME MEASURES: Bayley Scales of Infant Development-III Language Composite. RESULTS: M-Ins vs. P-Ins were similar in GA, BW, and age at BSID-III testing (mean 22.6 months adjusted), as well as other matched characteristics (all p ≥ 0.16). BSID-III Language Composite scores were lower in M-Ins than P-Ins (87.9 ± 11.3 vs. 101.9 ± 13.6) with a clinically significant effect size of 0.93 (p < 0.001). Overall, 45% of M-Ins exhibited mild to moderate language delay compared to 8% of P-Ins. Receptive and Expressive subscale scores also were lower in M-Ins than in P-Ins (both p < 0.001). CONCLUSIONS: In this preterm cohort, by toddler age, M-Ins was associated with lower scores on measures of overall language as well as receptive and expressive language skills. Our findings, showing such an early influence of SES on language outcome in a cohort matched for biomedical risk, suggest that very early language interventions may be especially important for low SES preterm toddlers.

Selective impact of early parental responsivity on adolescent stress reactivity.

Research in animals has shown that early life experience, particularly parenting behaviors, influences later-life stress reactivity. Despite the tremendous relevance of this finding to human development and brain function, it has not been tested prospectively in humans. In this study two aspects of parenting were measured at age 4 in a sample of healthy, low socioeconomic status, African American children, and stress reactivity was measured in the same children 11-14 years later using a modified version of the Trier Social Stress Test (n = 55). Salivary cortisol was measured before, during and after the stressor and data were analyzed using piecewise hierarchical linear modeling. Parental responsivity, independent of the use of physical discipline, was positively related to cortisol reactivity. Effects were independent of subjective appraisals of the stressor and were also independent of other environmental risk factors and current psychosocial functioning. Therefore this study demonstrates in a novel and precise fashion that early childhood parental responsivity prospectively and independently predicts stress reactivity in adolescence.

Working memory ability predicts trajectories of early alcohol use in adolescents: the mediational role of impulsivity.

AIMS: (i) To evaluate the role of pre-existing weakness in working memory ability (WM) as a risk factor for early alcohol use as mediated by different forms of impulsivity and (ii) to assess the adverse effects of progressive alcohol use on variations in WM over time. DESIGN, SETTING AND PARTICIPANTS: A community sample of 358 adolescents [48% males, mean(age) (baseline) = 11.4 ± 0.87 years] from a longitudinal cohort design, assessed annually over 4 consecutive years with less than 6% attrition. MEASUREMENTS: Repeated assessments were conducted for the following key variables: WM (based on performance on four separate tasks), frequency of alcohol use (AU) and three forms of impulsivity, namely sensation seeking (SS), acting without thinking (AWT) and delay discounting (DD). Latent growth curve modeling procedures were used to identify individual trajectories of change for all key variables. FINDINGS: Weakness in WM (at baseline) predicted significantly both concurrent alcohol use and increased frequency of use over the four waves (P < 0.05). This effect was entirely mediated by two forms of impulsivity, AWT and DD, both of which were characterized by underlying weakness in WM. No individual variation was observed in the slopes of WM, which suggests that individual variations in alcohol use were not associated with changes in WM in our early adolescent sample. CONCLUSIONS: Early adolescent alcohol use may be a consequence of (pre-existing) weaknesses in working memory (WM) rather than a cause of it. Efforts to reduce early alcohol use should consider the distinct roles of different impulsivity dimensions, in addition to WM, as potential targets of intervention.

Neighborhood disadvantage and adolescent stress reactivity.

Lower socioeconomic status (SES) is associated with higher levels of life stress, which in turn affect stress physiology. SES is related to basal cortisol and diurnal change, but it is not clear if SES is associated with cortisol reactivity to stress. To address this question, we examined the relationship between two indices of SES, parental education and concentrated neighborhood disadvantage, and the cortisol reactivity of African-American adolescents to a modified version of the Trier Social Stress Test (TSST). We found that concentrated disadvantage was associated with cortisol reactivity and this relationship was moderated by gender, such that higher concentrated disadvantage predicted higher cortisol reactivity and steeper recovery in boys but not in girls. Parental education, alone or as moderated by gender, did not predict reactivity or recovery, while neither education nor concentrated disadvantage predicted estimates of baseline cortisol. This finding is consistent with animal literature showing differential vulnerability, by gender, to the effects of adverse early experience on stress regulation and the differential effects of neighborhood disadvantage in adolescent males and females. This suggests that the mechanisms underlying SES differences in brain development and particularly reactivity to environmental stressors may vary across genders.

Suicidal ideation and self-harm behavior in a community sample of preadolescent youth: a case-control study.

OBJECTIVE: Research has focused on understanding risk factors associated with suicidal ideation and self-harm behaviors in older youth, but less is known regarding these behaviors in preadolescents. We examined characteristics associated with suicidal ideation and self-harm behavior in youth aged 10-13 years. DESIGN/METHODS: A community sample of 387 youth was enrolled in a prospective study assessing precursors of risk behaviors. Twenty-three subjects endorsing items regarding suicidal ideation or self-harm behaviors (Achenbach's Youth Self-Report) (endorsers) were matched with 23 non-endorsers. Groups were compared on problem behaviors, impulsivity, neurocognitive function, risk behaviors, and other variables. RESULTS: Endorsers had higher levels of impulsivity, were more likely in borderline/clinical range on 5 of 8 Youth Self-Report Syndrome scales, and reported more risk taking. Endorsers and non-endorsers were similar in neurocognitive function. More non-endorsers were on stimulants, but groups were similar in parental monitoring and parental report of behavioral/emotional issues, socioeconomic status, and marital status. CONCLUSION: In this study, preadolescent endorsers report significantly more problem behaviors than non-endorsers. However, parental monitoring and parent report of problems were similar between groups. Given these findings, we suggest that at-risk youth may be underrecognized at young ages.

Early adolescent sexual debut: the mediating role of working memory ability, sensation seeking, and impulsivity.

Although deficits in working memory ability have been implicated in suboptimal decision making and risk taking among adolescents, its influence on early sexual initiation has so far not been examined. Analyzing 2 waves of panel data from a community sample of adolescents (N = 347; Mean age[baseline] = 13.4 years), assessed 1 year apart, the present study tested the hypothesis that weak working memory ability predicts early sexual initiation and explored whether this relationship is mediated by sensation seeking and 2 forms of impulsivity, namely acting-without-thinking and temporal discounting. The 2 forms of impulsivity were expected to be positively associated with early sexual initiation, whereas sensation seeking was hypothesized to be unrelated or to have a protective influence, due to its positive association with working memory. Results obtained from structural equation modeling procedures supported these predictions and in addition showed that the effects of 3 prominent risk factors (Black racial identity, low socioeconomic background, and early pubertal maturation) on early sexual initiation were entirely mediated by working memory and impulsivity. The findings are discussed in regard to their implications for preventing early sexual onset among adolescents.