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.     

Cortisol Stress Response Variability in Early Adolescence: Attachment,Affect and Sex

Attachment, affect, and sex shape responsivity to psychosocial stress. Concurrent social contexts influence cortisol secretion, a stress hormone and biological marker of hypothalamic–pituitary–adrenal axis activity. Patterns of attachment, emotion status, and sex were hypothesized to relate to bifurcated, that is, accentuated and attenuated, cortisol reactivity. The theoretical framework for this study posits that multiple individual differences mediate a cortisol stress response. The effects of two psychosocial stress interventions, a modified Trier Social Stress Test for Teens and the Frustration Social Stressor for Adolescents were developed and investigated with early adolescents. Both of these protocols induced a significant stress reaction and evoked predicted bifurcation in cortisol responses; an increase or decrease from baseline to reactivity. In Study I, 120 predominantly middle-class, Euro-Canadian early adolescents with a mean age of 13.43 years were studied. The girls’ attenuated cortisol reactivity to the public performance stressor related significantly to their self-reported lower maternal-attachment and higher trait-anger. In Study II, a community sample of 146 predominantly Euro-Canadian middle-class youth, with an average age of 14.5 years participated. Their self-reports of higher trait-anger and trait-anxiety, and lower parental attachment by both sexes related differentially to accentuated and attenuated cortisol reactivity to the frustration stressor. Thus, attachment, affect, sex, and the stressor contextual factors were associated with the adrenal-cortical responses of these adolescents through complex interactions. Further studies of individual differences in physiological responses to stress are called for in order to clarify the identities of concurrent protective and risk factors in the psychosocial stress and physiological stress responses of early adolescents.     

Understanding the Influence of Mental Health Diagnosis and Gender on Placement Decisions for Justice-Involved Youth

Justice-involved youth have high rates of psychiatric diagnoses, and these youth are often placed out-of-home, although evidence identifies several negative implications of juvenile confinement, especially for youth with psychopathology. Furthermore, youth in the justice system may be processed differently based on gender. As males and females tend to manifest symptoms differently, the psychopathology of youth may act to moderate the relationship between gender and placement in the juvenile justice system. The present study used a large, diverse sample (n?=?9?851, 19.8?% female) to examine whether youth placed in various types of out-of-home facilities differed in terms of externalizing, internalizing, substance use, or comorbid disorders, and to determine the predictive value of mental health diagnoses in placement decisions. The moderation effect of psychopathology and substance use on the relationship between gender and placement also was explored. The results indicated that each type of disorder differed across placements, with internalizing being most prevalent in non-secure, and externalizing, comorbid, and substance use being most prevalent in secure settings. Mental health diagnoses improved the prediction of placement in each out-of-home placement beyond legal and demographic factors such that externalizing and substance use disorders decreased the likelihood of placement in non-secure settings, and internalizing, externalizing, and substance use disorders increased the likelihood of placement in secure and state-secure facilities. The relationship between internalizing pathology and placement in more secure facilities was moderated by externalizing pathology. The relationship between gender and placement was significantly moderated by mental health such that females with mental health diagnoses receive less secure placements. Implications for policymakers and practitioners are discussed, as well as implications for reforming juvenile justice within a developmental approach.     

“I'm Innocent!”: Effects of Training on Judgments of Truth and Deception in the Interrogation Room

The present research examined the extent to which people can distinguish true and false denials made in a criminal interrogation, and tested the hypothesis that training in the use of verbal and nonverbal cues increases the accuracy of these judgments. In Phase One, 16 participants committed one of four mock crimes (breaking and entering, vandalism, shoplifting, a computer break-in) or a related but innocent act. Given incentives to deny involvement rather than confess, these suspects were then interrogated. In Phase Two, 40 observers were either trained in the analysis of verbal and nonverbal deception cues or not trained before viewing the videotaped interrogations and making their judgments. As in past studies conducted in nonforensic settings, observers were generally unable to distinguish between truthful and deceptive suspects. In addition, those who underwent training were less accurate than naive controls—though they were more confident and cited more reasons for their judgments. The implications of these findings are discussed in light of what is known about police interrogations, false confessions, and the wrongful conviction of innocent suspects.     

The Effect of Jury Deliberations on Jurors' Reasoning Skills

The effect of jury deliberation on jurors' reasoning skill in a murder trial was examined. Specifically, the effect of deliberating on reasoning competence (as defined by Kuhn, Weinstock and Flaton, 1994) was explored. One hundred and four participants viewed a videotaped murder trial and either deliberated in 12-person juries or ruminated on the case individually. Among those assigned to juries, half had their reasoning skill assessed prior to deliberations, while the others were tested after deliberating. Jurors in the individual rumination condition were assessed after they had the opportunity to reflect on the case alone. As hypothesized, post-group-deliberation jurors were more likely to discount both the selected verdict and alternative theories and incorporate judgmental supporting statements than were the other mock jurors. However, the mock jurors did not differ with regard to making statements that supported alternative verdicts or including judgmental statements that discounted their chosen verdict. In terms of Kuhn's reasoning continuum from satisficing (low level) to theory–evidence coordination (high level), there is some evidence that post-group-deliberation jurors may be closer to the high end than predeliberation jurors or post-individual-rumination jurors in some aspects of the task, but not in others.     

Morphine perfused rabbits: a tool for experiments in forensic entomotoxicology

In order to establish an animal model for entomotoxicological studies, the kinetics of morphine elimination from blood after a single intravenous injection of morphine and the concentration of morphine in tissues following a continuous perfusion were studied. The aim of these experiments was to obtain controlled morphine tissue concentrations similar to those encountered in fatal human heroin overdoses. These tissues can be used as a food source for developing fly larvae in entomotoxicological studies. In the single injection experiment, seven rabbits were administered 1 or 2 mg/kg body weight of morphine chlorhydrate via the main ear artery. Blood samples of 200 microL were removed regularly via a catheter. Morphine concentration was determined using RIA techniques. Morphine was found to be first rapidly distributed and then slowly eliminated, following a two-exponential equation. Elimination of morphine from blood can be described as a two-compartment model. Constants of the equation were determined using the Kaleidagraph program. Using those constants, the main pharmacokinetics parameters were calculated. Results of these parameters showed the following: clearance from 13.3 to 16.2 L.h.1, half-life of the distribution phase from 0.6 to 0.9 min, and half-life of the elimination phase from 21 to 26 min. These results were used to calculate the rate of perfusion of morphine for rabbits to obtain desired, controlled, and constant concentrations of morphine in tissues. In the second experiment, three rabbits received a perfusion of morphine intravascularly at a rate of 2 mg/kg/h for a period of 3 h. These rabbits were sacrificed and analyses performed on several abdominal and thoracic organs. Results showed that the concentrations of morphine differed according to the organ analyzed, but were reproducible for organs between animals. These concentrations were similar to those normally encountered in cases of human death due to heroin overdoses.