Neurocognitive skills moderate urban male adolescents’ responses to preventive intervention materials

Abstract

The present experiment was designed to determine whether individual variation in neurobiological mechanisms associated with substance abuse risk moderated effects of a brief preventive intervention on social competency skills. This study was conducted in collaboration with the ongoing preventive intervention study at Johns Hopkins University Prevention Intervention Research Center (JHU PIRC) within the Baltimore City Public Schools. A subsample (N = 120) of male 9th grade students was recruited from the larger JHU study population. Approximately half of the participants had a current or lifetime diagnosis of CD while the other half had no diagnosis of CD or other reported problem behaviors. Measures of executive cognitive function (ECF), emotional perception and intelligence were administered. In a later session, participants were randomly assigned to either an experimental or control group. The experimental group underwent a facilitated session using excerpted materials from a model preventive intervention, Positive Adolescent Choices Training (PACT), and controls received no intervention. Outcomes (i.e., social competency skills) were assessed using virtual reality vignettes involving behavioral choices as well as three social cognition questionnaires. Poor cognitive and emotional performance and a diagnosis of CD predicted less favorable change in social competency skills in response to the prevention curriculum. This study provides evidence for the moderating effects of neurocognitive and emotional regulatory functions on ability of urban male youth to respond to preventive intervention materials.

Introduction

Evaluations of a number of interventions for the general adolescent population provide evidence for their effectiveness in preventing or delaying onset of drug abuse (see especially Botvin et al., 1995, Eggert et al., 1994, Kellam, 1999, Olds et al., 1998, Spoth et al., 1998, Thompson et al., 1997, Webster-Stratton and Hammond, 1997). However, in all cases, substantial benefits have accrued only to a subset of participants (Conduct Problems Prevention Research Group, 1992; Kellam and Anthony, 1998, Greenberg and Kusche, 1996, Rebok et al., 1996) suggesting that individual-level characteristics may moderate responsiveness to prevention programs. Few studies have, however, attempted to delineate the individual characteristics that portend outcome. Once these factors are identified, prevention success can be potentially improved by targeting intervention strategies to specific facets of risk for substance abuse. Research on vulnerability and protective factors suggests that tailored, targeted interventions will be most effective when psychosocial manipulations are “matched” to an individual's unique constellation of social, psychological, and biological attributes, thereby reinforcing more adaptive and normative phenotypes (Scheier and Botvin, 1995).

Notably, evidence is accumulating to demonstrate that neurocognitive processes, especially deficits in executive cognitive function (ECF) and emotional regulatory capacities, amplifies risk for drug abuse (Aytaclar et al., 1999, Deckel et al., 1995, Fishbein, 2000, Harden and Pihl, 1995, Peterson and Pihl, 1990, Giancola et al., 1996) and propensity to relapse in drug abusers in treatment (Bauer, 1997, Self, 1998, Winterer et al., 1998). ECF, largely regulated by the prefrontal cortex (PFC) (Giancola et al., 1996, Grant et al., 1978, Meek et al., 1989), includes several dimensions of higher order cognitive processing skills, such as strategic thinking, attention, impulse control, working memory and self-monitoring of behavior during goal directed motivation, and assessing the consequences of behavior (Andrew and Bentley, 1978, Fishbein, 2000, Shafer and Fals-Stewart, 1997, Giancola et al., 1996). Youths at high risk for substance use perform poorly on neuropsychological tests measuring various aspects of ECF capacity, particularly impulsivity, risky decision making, inability to delay gratification, and inattention (Aytaclar et al., 1999, Blume et al., 1999, Giancola et al., 1996, Giancola et al., 1998, Moss et al., 1997, Tarter et al., 1995, Weinberg, 1997).

Neurocognitive mechanisms that underlie the perception of emotional and social cues contribute to decision making within a social context. Emotional perception is modulated by neural connections between the PFC and limbic system. Deficits in ECF may affect emotional responses via a reduction in inhibitory controls and/or inaccurate appraisals of environmental or interpersonal inputs. Dysfunction of these emotional centers within the limbic system and PFC may play a direct, instrumental (not just a subservient) role in behavioral problems such as drug abuse by compromising the ability to regulate reactions to such inputs (Fishbein et al., 2005b, Weiss et al., 2001). Cognitive tasks that include an emotional component (e.g., aversive stimuli or penalties) invoke specific interconnected regions of the PFC and limbic system, suggesting that when task demands modify emotional functions, neural responses occur within this network (Elliott et al., 2000, Liberzon et al., 2000). Thus, a functional disconnection between the PFC and limbic regions may be responsible for a developmental lag in social competency skills, including disinhibited behavior, poor decision making, and poor emotional regulation (Davidson et al., 2000). In essence, the ability to perceive emotional cues and regulate affective responses in the form of effective and adaptive behaviors may be equally as important as higher order cognitive skills in understanding various competencies, including risk for drug abuse and ability to process and act on intervention curriculum materials.

Inasmuch as the prefrontal cortex does not functionally mature until early adulthood, ECF capacities accordingly improve with age; as children develop, they become more accurate, process information more quickly, and do so with increasing complexity and ease (Morris, 1998). It is thus plausible that the ECF impairments observed in high-risk youths reflect a neuromaturational disturbance. Given critical connections between the PFC and limbic structures, it is not surprising that childhood psychological characteristics associated with substance abuse risk also encompass disturbances in emotional regulation and behavioral undercontrol (Barkley et al., 1992, Nigg et al., 1999). In adolescence, maturational lags in the complexity and automaticity of ECF precursors become more obvious and may increase the likelihood of risk behaviors.

Externalizing behaviors such as conduct disorder (CD), frequently shown to magnify the risk for substance abuse (Clark and Cornelius, 2004, Chilcoat and Breslau, 1999, Tarter et al., 1999), are associated with impaired ECF capacity, behavioral dysregulation and deficient modulation of emotion (Bauer et al., 2001), suggestive of developmental delays (Giancola and Moss, 1998). CD children, particularly with the early age onset variant (Moffitt, 1993), may insufficiently experience emotional responses to negatively sanctioned behaviors and, thus, have a greater likelihood of engaging in high-risk behaviors. For these children, the prognosis is poor (Ruchkin et al., 2003, Herpertz et al., 2003, Dalsgaard et al., 2002). Whether prognoses can be improved following preventions tailored to the specific facets underlying the disorder and other related behaviors has yet to be determined.

Refraining from drug abuse requires development of multiple capacities, including risk appraisal, perception of social interpersonal cues, behavioral control and emotion modulation. Thus, delineating particular ECF and emotional substrates of behavioral disorders related to and including drug abuse may provide valuable insights for developing therapeutic interventions for children who tend to be refractory to both conventional and novel treatments. Intact ECF and its regulation of emotional tone may, in fact, be a prerequisite for a favorable response to any prevention or treatment program that involves cognitive processing of curriculum materials.

The model tested in the present experiment is based on the hypothesis that, while certain neurocognitive and emotional deficits may antedate and possibly contribute to drug abuse in general, specific functions may further moderate an individuals’ ability to respond to intervention materials. Adolescents with and without CD were facilitated through a component of a selective intervention developed for high-risk urban minority youth that, similar to other programs, targets problem solving, sensitivity to consequences, regulating emotions, and resisting impulses. Processing of program materials requires children to (a) be cognizant of and responsive to potential negative consequences of their behavior, (b) inhibit inappropriate behavioral responses, (c) understand and act on the benefits of deliberate and cautious decision making, and (d) process and translate new information and social-cognitive skills training into pro-social behavior. This large laboratory-based experiment is the first attempt to explore the possibility that adolescents with deficiencies in these complex skills are less likely to benefit from universal prevention programs as adolescents with relatively higher levels of ECF and emotional regulation.