Complete results are available upon request. Two sets of temperament by monitoring interactions replicated across both substance use and intention variables – those involving effortful control and depressive mood. Results suggested that parental monitoring had very little association with substance use intentions and substance use in 9th grade for adolescents with high levels of effortful control in 5th grade. However, parental monitoring was a significant predictor of these variables when adolescents were low in effortful control. Likewise, monitoring was primarily a protective factor when depressed mood was relatively high in 5th grade. These interactions are illustrated in Figures 1 and Figure 2. In short, there were indications that parental monitoring might be most relevant for youth with dispositional tendencies associated with substance use. We then evaluated concurrent relations using 9th grade data. Selected results are presented in Table 6. Significant results were restricted to the substance use intention variable, but the effortful control and depressive mood pattern was replicated. In general, the significant patterns were consistent with the prospective analyses and indicated that monitoring was a stronger predictor for youth with temperamental dispositions that placed them at risk for greater substance use . However, these interactions were restricted to only one substance use variable, and thus should be viewed with caution. We investigated the prospective influence of temperament and parental monitoring on substance use using data from a longitudinal study of Mexican-origin youth and their families. We focused on willingness to use substances , expectations for positive outcomes , and lifetime use of alcohol, cigarettes, and other drugs. The rates of substance use in this sample were similar to what has been reported for Hispanic adolescents in nationally representative surveys . Specifically, around 40% of participants had tried a substance at least once by 9th grade , and furthermore, considerably more participants had tried a substance by 9th grade compared to 5th grade. These rates are thus also similar to what has been reported for European American and African American adolescents,pruning cannabis and higher than what has been reported for Asian American adolescents .

As expected, low effortful control and high aggressive tendencies assessed in 5th grade were the most robust predictors of substance use variables in 9th grade. These findings fit with previous research indicating that temperamental traits related to impulsivity are associated with substance use . Moreover, these associations held while controlling for previous levels of the substance use variables in 5th grade . This finding is consistent with White and colleagues’ suggestion that aggression serves as a risk factor for future substance use irrespective of previous use. These longitudinal findings are particularly noteworthy because Mexican Americans are the largest and fastest growing ethnic minority group in the United States, yet this population has received relatively little attention in research on the temperamental correlates of substance use. Beyond finding evidence that temperament prospectively predicts substance use, we also examined the main and interactive effects of parenting monitoring. Consistent with previous research , child-reported parental monitoring in 5th grade was associated with 9th grade substance use variables, even after controlling for prior levels. In contrast, parent reports of monitoring had only concurrent associations with substance use variables. Although the greater predictive power of child reports could simply reflect shared method biases, we believe that a pure methodological explanation is unlikely to fully account for the findings. Instead, we suspect that youth perceptions of parental behaviors are especially salient developmental considerations when attempting to understand risk for substance use. Youth who believe their behavior is being monitored will likely behave differently than youth who do not believe there is surveillance of their behaviors. Indeed, beliefs about parental behaviors and values might be more consequential than actual parental behaviors and values for understanding adolescent substance use. This is consistent with Voisine and colleagues’ suggestion that parental injunctive norms are more effective in preventing substance use than parental monitoring per se.

Nonetheless, further research is needed to better understand the relative importance of child vs. parent reported monitoring for substance use outcomes. We found a number of significant interactions between temperament and child-reported parental monitoring. Most notably, both effortful control and depressive mood interacted with monitoring in 5th grade to predict intentions and use in 9th grade. These interaction effects suggest that parental monitoring is a protective factor for youth with the temperamental tendencies associated with risk for substance use. Considered from another perspective, the interaction effects suggest that certain temperamental traits are risk factors for substance use when parental monitoring is low, but not when it is high. Either interpretation is consistent with the findings and points to a similar conclusion about how temperament and parenting work together to increase risk for early substance use. Being raised in a home with a perception of minimal monitoring by parents may be a more salient risk factor for substance use for those adolescents with dispositional proclivities toward substance use, and possessing a disposition toward substance use may be a stronger risk factor when youth do not believe they are closely monitored by their parents. The broader developmental consideration is that temperamental factors and family variables should be considered jointly in models that attempt to understand early risk for substance use. Although the current study was notable for its multi-informant longitudinal design, and for the size and ethnic composition of the sample, there are limitations that merit consideration. For instance, our ability to detect effects for surgency was hampered by the low reliability of the scale in the 5th grade; thus, results involving surgency should be interpreted with caution. Also, we relied exclusively on youth reports of their substance use, intentions, and expectancies. However, intentions and expectancies are inherently subjective variables and are thus best assessed via self-report. Likewise, focal youth might be in the best position to report on their actual use given understandable motivations to hide substance use from parents, teachers, and other potential informants. In closing, we found evidence from a longitudinal study of Mexican-origin youth that temperament and parental monitoring assessed in 5th grade are prospectively related to substances use outcomes in 9th grade.

These findings are important because they suggest that theoretical models concerning the influence of temperament on substance use can be applied to adolescents of Mexican origin. Indeed, we suspect that factors like temperament and parental monitoring have transcontextual validity to the extent that they are risk factors for early substance use for a diverse range of youth. Of particular importance, we also found that relatively high levels of perceived monitoring might attenuate some of the risks associated with dispositional tendencies toward substance use. Although the current results should be replicated, we suggest that future intervention and prevention efforts could be enhanced by attending to individual differences in temperament. Such attention might be especially important when considering efforts to increase parental monitoring. Alcohol remains the most commonly used substance of abuse during adolescence and young adulthood. The act of binge drinking, often defined as the consumption of greater than either 4 or 5 drinks in a given drinking episode,dry room is of particular concern in youth given the host of associated negative consequences and potential for neurological alterations to the developing adolescent brain . Approximately 17% of 12th graders and 33% of college-aged young adults reported recent binge drinking, defined as the consumption of 5 or more drinks in a row at least once in the two weeks prior to assessment . Notably, almost 1% of adolescents aged 12 to 17 and 10% of young adults aged 18 to 25 engage in binge drinking episodes frequently, averaging more than once per week over the previous 30 days . Frequent binge drinking during adolescence is associated with elevations in multiple risk factors, including adolescent drug use, antisociality, and parent alcoholism , as well as a number of negative consequences in adulthood such as alcohol use disorder diagnosis, drug use, psychiatric morbidity, homelessness, legal problems, accidents, and lower social class . Importantly, many of these elevated risks are greater for those who frequently binge drink during adolescence, as opposed to those who are infrequent/moderate binge drinkers , suggesting that the frequency with which one binges during adolescence is an important factor in future alcohol-related outcomes. Thus, given the known neurotoxicity of alcohol at higher doses , efforts to predict who is at risk of drinking at these frequent high levels during the critical period of neurodevelopment are warranted.In line with this, diminished inhibitory control during adolescence is consistently implicated as a risk factor for future alcohol and substance use . Successful inhibitory control likely involves the ventral attention, fronto-parietal and fronto-striatal networks, including regions such as the inferior frontal gyrus extending to the insula, cingulate and paracingulate gyri, superior parietal gyrus, and basal ganglia structures , suggesting deficiencies in these networks may serve as correlates of alcohol-related risk prior to binge drinking onset . Longitudinal functional magnetic resonance imaging studies of adolescents have identified several neural aberrations during inhibition, as measured on the Go/No-go task, as significant predictors of greater alcohol and substance use, even in the absence of behavioral differences on the tasks . Specifically, greater left angular gyrus and less ventromedial prefrontal blood-oxygen-leveldependent activation during no-go correct rejection vs. go trials in 16 to 19 yearolds was found to predict higher levels of alcohol and substance use and dependence symptoms over an 18-month follow-up.

This effect was especially pronounced for adolescents who were high frequency substance users at baseline . In an analysis of 12–14 year-olds scanned prior to the onset of alcohol use and followed up about 4.2 years later, less BOLD response in regions including the right inferior frontal gyrus, left dorsal and medial frontal areas during no-go correct rejection vs. baseline trials was found to differentiate between those who transitioned to alcohol use from those who remained continuous controls ; however, the activation in those regions was found to be associated with attention problems at follow-up, and not substance use outcomes per se, suggesting the groups may have differed on multiple related factors. In an additional longitudinal analysis of 11–16 year-olds, with follow-up approximately 3 years later, adolescents who transitioned into drinking by follow-up exhibited less BOLD response during no-go correct rejection vs. go trials at baseline in bilateral middle frontal gyri, left putamen, right inferior parietal lobule, and left cerebellar regions. Yet increased activation was observed after the onset of heavy drinking in all regions except the putamen, as compared to matched continuous non-drinkers who displayed decreased activation in these regions at follow-up . These results suggest alcohol-exposure may increase engagement of these neural networks in order to successfully inhibit prepotent responses; however, the degree of alcohol exposure required to produce this change has yet to be investigated. Taken together, the current literature implies the presence of a pre-existing neural inhibition risk profile for future alcohol and substance use, along with a potential for additional alcohol and substance-related disturbances in normal neural inhibitory maturation processes. However, the neural underpinnings subserving the transition from moderate, arguably even “normative”, alcohol use behavior in adolescence to the extremely high-risk pattern of frequent binge drinking have not been determined. Thus, the present study seeks to prospectively predict the time to transition to high-risk frequent binge drinking from the neural patterns of successful inhibitory control in a single sample of adolescents who were already engaged in moderate alcohol use. Given the broad set of inhibitory-related regions identified in the earlier literature, a whole-brain exploratory approach was used for the present analysis, with a general hypothesis of alcohol risk-related activation to fall within the fronto-parietal and fronto-striatal networks. No directionality was hypothesized for the present analyses given the mixed results of the literature and the novelty of the current inquiry. Current study data was culled from a larger, ongoing longitudinal substance use and neuroimaging project . Participants at baseline were healthy 12–14 year-olds, recruited through schools in the San Diego area, with very minimal to no experience with alcohol or drugs. Exclusionary criteria for the parent study at baseline included: premature birth prior to the 35th gestational week; report of prenatal alcohol or illicit drug exposure; history of any DSM-IV Axis I or neurological disorder; psychoactive medication use; loss of consciousness or head trauma; learning disability or mental retardation; chronic medical illness; history of alcohol use ; history of drug use ; non-correctable sensory problems; and inadequate English comprehension.