Magnitude and duration of the effects of cocaine on conditioned and adjunctive behaviors in the chimpanzee.

Characteristic patterns of conditioned key-pressing were maintained in the chimpanzee under a multiple 30-response fixed-ratio, 10-minute fixed-interval schedule of food presentation. Adjunctive drinking occurred with regularity during the fixed-interval schedule and, with less frequency, during 1-minute timeout periods that followed each food presentation; drinking seldom occurred during the fixed-ratio schedule. Cocaine increased key pressing under the fixed-interval schedule at doses between .1 and 3.0 mg/kg, but adjunctive drinking and key pressing under the fixed-ratio schedule did not increase at any dose. Conditioned and adjunctive behaviors were disrupted and suppressed for different durations at 10,0 mg/kg, a dose which induced convulsive seizures within 10 minutes after intramuscular injection. A time-course analysis showed the magnitude and duration of the effects of cocaine on key pressing under the fixed-interval schedule and on adjunctive drinking to be dose-related. Moreover, a given dose of cocaine had diverse effects, depending on the behavior and the time since drug administration.     

A Case Study of Interpersonal Emotion Regulation Within a Varsity Volleyball Team

This study used an instrumental case study approach to investigate the ways teammates within a female varsity volleyball team regulated one another's emotions, the factors that were perceived to influence interpersonal emotion regulation (IER), and athletes' preferences for regulating their own and others' emotions. Fourteen athletes participated in semistructured interviews and reported using a variety of emotion-improving and emotion-worsening IER strategies, in addition to occasionally choosing not to engage in IER, and several factors were found to influence IER (e.g., athletes' roles and interpersonal factors). This study has theoretical implications and applied implications for athletes, coaches, and sport psychology consultants.     

Measuring Abuse Sequelae: Validating and Extending the Trauma Symptom Checklist–40

This study used the Trauma Symptom Checklist–40 (TSC–40) to index both childhood sexual abuse (CSA) and childhood physical abuse (CPA) in a college student sample of both men and women (N = 441). Although the TSC–40 was designed as a measure of CSA trauma, this study concludes the measure is appropriately reliable for indexing the traumatic sequelae of CPA as well as CSA in nonclinical samples. This study also explored the effects of gender and abuse severity on resulting symptomatology, finding that women and severely abused individuals report the most negative sequelae. Both CSA and CPA emerged as significant explanatory variables in TSC–40 scale scores beyond gender, supporting its validity for indexing traumatic sequelae in nonclinical samples.     

Cumulative Risk,Emotion Dysregulation,and Adjustment in South African Youth

Research on cumulative risk is growing, however, little work has occurred in low- or middle-income countries, and few studies have focused on processes linking risk to outcomes. This study explored relations between components of cumulative risk and adjustment in a sample of 324 South African youth (M age?=?13.11 years; SD?=?1.54 years; 65% female; 56% Black/African; 14% Colored; 23% Indian; 7% White), and tested competing models of emotion dysregulation as a mediator or moderator of risk—adjustment links. Data was collected from youth and their female caregivers during home interviews. Structural equation models and regression analyses accounting for age and sex contributions revealed that emotion dysregulation mediated associations between sociodemographic risk and internalizing symptoms, externalizing problem behavior, and drug use severity, and moderated links between psychosocial risk and internalizing symptoms and externalizing problem behavior. For the mediator models, sociodemographic risk was associated with impaired emotion regulation, which in turn was linked with heightened adjustment difficulties. For the moderator models, psychosocial risk was linked with adjustment problems only when emotion dysregulation was high. These data indicate the importance of disentangling components of cumulative risk. Future research within the South African cultural context might build on these findings by adapting and testing school- or family-based prevention or intervention programs that include modules on emotion regulation.     

Impulsivity Symptoms as Core to the Developmental Externalizing Spectrum

Impulsivity is posited to be a key part of the externalizing spectrum during childhood, but this idea has received minimal empirical attention. The goal of the present investigation was to utilize network analysis to determine whether behavioral impulsivity symptoms are key components of the externalizing network across several developmental periods from preschool into adolescence. Participants were 109 preschoolers (64 % male) ages 3 to 6, 237 children (59 % male) ages 6 to 9, 372 children (59 % male) ages 10 to 13, and 357 adolescents (59 % male) ages 13 to 17 and their parents. Parents completed ratings of Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) symptoms on a well-validated rating scale. Network analyses indicated that ADHD and ODD were somewhat differentiated in preschool, becoming united by behavioral impulsivity symptoms during early childhood, and then differentiating into inattention versus externalizing clusters later during childhood and in adolescence. Behavioral impulsivity symptoms were core to the externalizing spectrum across most developmental periods, but core inattentive and ODD symptoms were also identified in line with progressive differentiation. These results suggest the increasing importance of impulsivity symptoms across development, explaining externalizing comorbidity and potentially serving as a viable target for childhood interventions for externalizing problems.     

ODD Symptom Network during Preschool

Several different conceptualizations of Oppositional Defiant Disorder (ODD) symptoms have been proposed, including one undivided set of symptoms (DSM-IV-TR; APA 2000); two domains of symptoms subdivided into affective and behavioral; and three domains of symptoms subdivided as angry/irritable, argumentative/defiant, and spiteful. The current study utilizes a novel approach to examining the division of ODD symptoms through use of network analysis. Participants were 109 preschoolers (64 male) between the ages of three and six (M = 4.34 years, SD = 1.08) and their parents and teachers/caregivers, who provided ratings of ODD symptoms. Results are consistent with one-, two-, and three- cluster solutions of ODD, but perhaps provide most support for the three-cluster solution. In addition, results support the idea that negative affect, particularly anger, forms the core of the ODD symptom network during preschool. These results suggest the importance of targeting anger in preschool interventions for ODD.     

Does drawing facilitate older children's reports of emotionally laden events?

Although it is well‐established that drawing about an event increases the amount of verbal information that young children provide during an interview, it is unclear whether drawing continues to facilitate children's reports as they get older. In the present experiment, 90 children, ranging from 5‐ to 12‐years old, were asked to draw and tell or to just tell about emotional events they had experienced. Children of all ages reported more information when asked to draw and tell rather than to tell only. Drawing had no negative effect on the accuracy of children's accounts. Drawing also increased the number of open‐ended questions and minimal responses that interviewers used. We conclude that drawing may be a useful tool in clinical and forensic settings with children of all ages; it increases the amount of information that children report and the number of appropriate questions that interviewers ask. Copyright © 2009 John Wiley & Sons, Ltd.     

One-month-old human infants learn about the social world while they sleep

Although infants display preferences for social stimuli early in their lives, we know relatively little about the mechanisms of infant learning about the social world. In the current set of studies, 1-month-old infants underwent an adapted eyeblink conditioning paradigm to examine learning to both 'social' and non-social cues. While infants were asleep, they were presented with either a 'social' stimulus (a female voice) or one of two non-social stimuli (tone or backward voice) followed by an airpuff presented to the eyelid. Infants in the experimental groups displayed increased learning across trials, regardless of stimulus type. However, infants conditioned to the 'social' stimulus showed increased learning compared to infants conditioned to either of the non-social stimuli. These results suggest a mechanism by which learning about the social world occurs early in life and the power of ecologically valid cues in facilitating that learning.     

Deconstructing the tower: Parameters and predictors of problem difficulty on the Tower of London task

The Tower of London (TOL) task has been widely used in both clinical and research realms. In the current study, 104 healthy participants attempted all possible moderate- to high-difficulty TOL problems in order to determine: (1) optimal measures of problem solving performance, (2) problem characteristics, other than the minimum moves necessary to solve the problem, that determine participants’ difficulty in solving problems successfully, quickly, and efficiently, and (3) effects of increased task experience on which problem characteristics determine problem difficulty. A factor analysis of six performance measures found that, regardless of task experience, problem difficulty could be captured well either by a single factor corresponding to general quality of solution or possibly by three subordinate factors corresponding to solution efficiency, solution speed, and initial planning speed. Regression analyses predicting these performance factors revealed that in addition to a problem’s minimum moves three problem parameters were critical in determining the problem difficulty: goal position hierarchy, start position hierarchy, and number of solution paths available. The relative contributions of each of the characteristics strongly depended on which performance factor defined performance. We conclude that TOL problem performance is multifaceted, and that classifying problem difficulty using only the minimum moves necessary to solve the problem is inadequate.