Peers increase adolescent risk taking by enhancing activity in the brain's reward circuitry

The presence of peers increases risk taking among adolescents but not adults. We posited that the presence of peers may promote adolescent risk taking by sensitizing brain regions associated with the anticipation of potential rewards. Using fMRI, we measured brain activity in adolescents, young adults, and adults as they made decisions in a simulated driving task. Participants completed one task block while alone, and one block while their performance was observed by peers in an adjacent room. During peer observation blocks, adolescents selectively demonstrated greater activation in reward-related brain regions, including the ventral striatum and orbitofrontal cortex, and activity in these regions predicted subsequent risk taking. Brain areas associated with cognitive control were less strongly recruited by adolescents than adults, but activity in the cognitive control system did not vary with social context. Results suggest that the presence of peers increases adolescent risk taking by heightening sensitivity to the potential reward value of risky decisions.     

Magnitude judgments of loudness change for discrete, dynamic, and hybrid stimuli

Recent investigations of loudness change within stimuli have identified differences as a function of direction of change and power range (e.g., Canévet, Acustica, 62, 2136–2142, 1986; Neuhoff, Nature, 395, 123–124, 1998), with claims of differences between dynamic and static stimuli. Experiment 1 provides the needed direct empirical evaluation of loudness change across static, dynamic, and hybrid stimuli. Consistent with recent findings for dynamic stimuli, quantitative and qualitative differences in pattern of loudness change were found as a function of power change direction. With identical patterns of loudness change, only quantitative differences were found across stimulus type. In Experiment 2, Points of Subjective loudness Equality (PSE) provided additional information about loudness judgments for the static and dynamic stimuli. Because the quantitative differences across stimulus type exceed the magnitude that could be expected based upon temporal integration by the auditory system, other factors need to be, and are, considered.     

Trait and state negative affect interactions moderate inhibitory control performance in emotionally loaded conditions

Following the framework that controlled performance is dependent upon cognitive and emotional processes which are inherently inter-linked, effects of trait and state negative affect (NA) on inhibitory control (IC) were studied in two experiments using an emotional day-night task (EDNT) - an inhibition based decision-making task embedded with emotional content. It was hypothesized that the effects of processing negatively loaded stimuli would depend on trait levels of negative and positive affects, particularly in conditions that entail IC. In Experiment 1, EDNT performance was compared with performance of an emotionally loaded control task that required to perform a dominant response rather than to inhibit it. In Experiment 2, EDNT performance was compared with an emotionally loaded control task that required performing an alternative rule which did not involve inhibiting the dominant response. Results of both Experiments showed that participants high on NA trait reactivity showed improved performance while processing ‘sad’ content, only in the inhibitory task and not in either of the control tasks. Results point to an interaction of trait and state factors in IC, and highlight the notion that heightened NA may sub-serve inhibition in sad contexts, which require counter-intuitive operations.     

Willem Blok's Contribution to Abstract Algebraic Logic

Willem Blok was one of the founders of the field Abstract Algebraic Logic. The paper describes his research in this field. Dedicated to the memory of Willem Johannes Blok     

Conditional associative learning of spatial and object information in children with attention deficit/hyperactivity disorder.

The present study assessed frontostriatal mediated memory functions in children with ADHD (N=12) and healthy control participants (N=12) using two tests of conditional associative learning (i.e., object and spatial) that shared similar stimulus-response association structures but that differed in terms of the demands placed upon strategic processes. Children with ADHD displayed normal performance on the object learning task but were impaired on the spatial learning task that placed greater demands on internally derived strategic processes. Secondary analyses further indicated that this strategic processing impairment cannot be attributed specifically to perseverative or working memory errors but rather appears to be related to a more general inability to maintain a high degree of consistency in responding across trials. Although the results of this study must be interpreted in light of the small sample sizes, they suggest that ADHD does not produce a basic deficit in acquiring stimulus-response associations previously shown to be associated with basal ganglia dysfunction. Rather, these findings suggest that the impaired conditional associative learning performance of children with ADHD is attributable to deficits in strategic processes previously been found to be dependent upon the integrity of the prefrontal cortex.     

The Role of Theistic Spirituality in Adolescent Girls' Body Esteem: A Pilot Outcome Study

A pilot outcome study explored associations between psychospiritual variables and body esteem in adolescent girls at a Roman Catholic high school by examining the influence of The Imago Dei Experience (TIDE), an intervention program the first author designed. Perception of God's loving acceptance accounted for significant variance in weight and appearance body esteem; religious crisis accounted for significant variance in weight body esteem. Lack of significant changes in body esteem from pretest to 18‐month follow‐up suggested the TIDE program may have buffered the typical increase in body dissatisfaction over that period of time for adolescent girls. The authors recommend counselors explore qualities of God image and religious crisis with adolescent girls.     

Mental Contamination in Obsessive-Compulsive Disorder: Associations With Contamination Symptoms and Treatment Response

The most common symptom of obsessive-compulsive disorder (OCD) is contamination fear. Feelings of contamination can be provoked through contact with a physical contaminant, referred to as contact contamination (CC), as well as in the absence of one, referred to as mental contamination (MC). Prior research indicates that CC and MC are distinct, and MC may interfere with treatment for CC. However, no study to date has examined how MC may be associated with responses to physical contaminants and treatment response for CC. This study examined the relationships between CC and MC in a sample of individuals with elevated contamination symptoms (N = 88), half of whom met diagnostic criteria for OCD. Participants engaged in three sessions of exposure and response prevention (ERP) for CC and completed self-report measures and behavioral tasks assessing CC and MC at pretreatment, posttreatment, and follow-up. As hypothesized, at pretreatment, MC was positively associated with reactivity to physical contaminants, even after participants washed their hands. ERP for CC was associated with unique changes in CC and MC across self-report and behavioral measures, and greater pretreatment MC predicted greater posttreatment CC, though this effect was evident in only one of two CC measures. Additionally, specificity analyses indicated changes in MC were independent of changes in disgust propensity, a related construct. Pretreatment disgust propensity also predicted treatment outcome, though the addition of pretreatment disgust propensity as a covariate reduced the relationship between pretreatment MC and posttreatment CC to nonsignificance. Results suggest MC plays an important role in the manifestation and treatment of CC symptoms and may represent a manifestation of disgust proneness. Theoretical and clinical implications are discussed.     

The Mentality of Apes Revisited

Although early comparative psychology was seriously marred by claims of our species'supremacy, the residual backlash against these archaic evolutionary views is still being felt, even though our understanding of evolutionary biology is now sufficiently advanced to grapple with possible cognitive specializations that our species does not share with closely related species. The overzealous efforts to dismantle arguments of human uniqueness have only served to show that most comparative psychologists working with apes have yet to set aside the antiquated evolutionary "ladder." Instead, they have only attempted to pull chimpanzees up to the ladder's highest imaginary rung — or perhaps, to pull humans down to an equally imaginary rung at the height of the apes. A true comparative science of animal minds, however, will recognize the complex diversity of the animal kingdom, and will thus view Homo sapiens as one more species with a unique set of adaptive skills crying out to be identified and understood.     

Oral Examination Anxiety in Physicians, Narcissism, and Object Relations

By applying object relations theory, both examiners and candidates can increase understanding of examination anxiety in oral certification in order to enhance the fairness and validity of the examinations. Unconscious images of self and others which examiners and candidates may project onto each other can affect the examination. The examiner must observe himself, the candidate, and the other examiner, lest a transference affecting the examination's progress occur, and to avoid an enactment, which may interfere with the examination. This observing should appropriately support the candidate in functioning at an optimal level of competence. Unconscious processes may prejudice the examiner's attitude towards a candidate, thus jeopardizing the examination's fairness and validity. The candidate's anxiety, based on projections onto the examiners, may interfere with his/her optimal functioning and affect the outcome. If a candidate's anticipatory anxiety is excessive, he/she needs to decide if it needs to be managed on a symptomatic or psychotherapeutic basis. Candidate and examiner both need to monitor their feelings during the examination in order to optimise the examination's fairness and validity. All these issues may also be considered in the relationship between psychiatric educators and trainees.