Differential effects of beta-adrenergic receptor blockade in basolateral amygdala or insular cortex on incidental and associative taste learning

The importance of central β-adrenergic system has been essentially investigated in aversive/emotional learning tasks. However, recent data suggest that the β-adrenergic system is also required for incidental taste learning. In the present study we evaluated in rats whether β-adrenergic receptor activity is required for taste habituation, an incidental taste learning, and also for conditioned taste aversion (CTA) learning, an associative learning. To address this issue, a low dose of the β-adrenergic antagonist propranolol was infused before learning in either the basolateral amygdala (BLA) or the insular cortex (IC), two forebrain areas reported to play a key role in taste memory formation. Incidental taste learning was assessed using a single presentation of the sweet taste saccharin 0.1%, which is sufficient to increase saccharin consumption (relative to water baseline) during a second presentation. CTA was assessed by pairing the first saccharin 0.1% presentation with a delayed gastric malaise, thus causing a decrease in saccharin consumption (relative to water baseline) during a second presentation. Propranolol infusion in BLA (1 μg/0.2μl) or IC (2.5 μg/0.5 μl) before the first taste exposure impaired incidental taste learning but did not affect CTA. These results highlight the important role played by the β-adrenergic receptor activation in cortical and amygdaloid structures during taste learning. Moreover, they are the first to suggest that incidental learning is more sensitive to blockade of noradrenergic system than associative learning.     

Systemic administration of a nitric oxide synthase inhibitor impairs fear sensitization in the plus-maze

The aim of the present study was to evaluate the occurrence of fear sensitization in rats previously treated with an inhibitor of the NO syntheses and submitted to Trial1/Trial2 plus-maze (PM) procedure. Male Wistar rats received a systemic treatment with N(omega)-nitro-L-Arginine-methyl ester (L-NAME; 5, 10 or 50 mg kg(-1)) and were submitted to PM Trial1. In the following day the animals were re-exposed to the PM with no drug administration (Trial2). Some standards spatial-temporal measures, such as the percentage of entries (% Open arm entries) and time spent (% Open arm time) in the open arms and risk assessment frequency were recorded and used to estimate the animal level of fear sensitization in PM Trial2. The results showed that animals receiving L-NAME (50 mg kg(-1)) displayed increased % Open arm entries and % Open arm time in Trial2 in relation to the group receiving 0.9% saline, which is compatible with impaired fear/anxiety acquisition during Trial1/Trial2 PM procedure. In addition, rats treated with L-NAME (50 mg kg(-1)) exhibited low level of risk assessment in Trial2 in relation to the group treated with 0.9% saline, which indicates low level of fear/anxiety during PM re-exposure. The number of entries into the enclosed arms was not changed by any L-NAME treatment, which suggests no bias of the drug treatments on animal locomotor activity. The data suggest that NO synthesis may mediate the fear sensitization process in the PM.     

Measuring Latinos' perceptions of depression: a confirmatory factor analysis of the Illness Perception Questionnaire

This study examined the psychometric properties of the Revised Illness Perception Questionnaire adapted for a clinical sample of low-income Latinos suffering from depression. Participants (N = 339) were recruited from public primary care centers. Their average age was 49.73 years and the majority was foreign born females of either Mexican or Central American descent. Confirmatory factor analysis was used to test the factor structure of this measure. Construct and discriminant validity and internal consistency were evaluated. After the elimination of three items because of low factor loadings (< .40) and the specification of seven error covariances, a revised model composed of 24 items had adequate goodness-of-fit indices and factor loadings, supporting construct validity. Each of the subscales reported satisfactory internal consistency. Intercorrelations between the 5 illness perception factors provided initial support for the discriminant validity of these factors in the context of depression. The establishment of the psychometric properties of this adapted measure will pave the way for future studies examining the role illness perceptions play in the help seeking and management of depression among Latinos.     

Effects of trusting and being trusted on team citizenship behaviours in chain stores

Previous studies showed a robust and positive relationship between subordinates' trust for leaders and their individual organizational citizenship behaviours. Building on this foundation, we examined two extensions. First, based on the team citizenship behaviours approach, we studied whether the same relationship held at the group level. Second, drawing from literature on leadership and self-efficacy, we studied whether leaders' perceptions of being trusted by their subordinates mattered in this trust relationship; we also examined how this perception affected team citizenship behaviours. Results showed that subordinates' trust for leaders and team citizenship behaviours were positively related at the team level. When leaders felt more trusted, teams showed more citizenship behaviours. Beyond these main effects, leaders' felt trust was found to negatively moderate the relationship between staff trust for leaders and team citizenship behaviours. Theoretical and practical implications of this research are discussed.     

Pronorm and antinorm deviants: a test of the subjective group dynamics model

The authors replicated the study by D. Abrams, J. M. Marques, N. Bown, and M. Henson (2000, Study 2), performed to test the subjective group dynamics model (J. M. Marques, D. Abrams, D. Paez, & C. Martinez-Taboada, 1998). Participants were students enrolled in the psychology department at an Italian university. The present study considered the relationship between students and professors, and the attitude object was limited enrollment for admission to the department. Participants evaluated either in-group or out-group members. Findings replicated those of Abrams et al., except the in-group pronorm deviant was perceived to be less typical and evaluated less positively than the normative members. This finding suggests that, during an intergroup conflict, perception of the typicality of deviants exaggerating the in-group norms--and thus their evaluations--may increase as long as deviance is not perceived to be too accentuated.     

The impact of relational demographics on perceived managerial trustworthiness: similarity or norms?

Perceived trustworthiness is a critical antecedent of interpersonal trust, yet researchers have a limited understanding of how such perceptions are generated. The authors used 2 competing perspectives within the relational demography literature--similarity-attraction and relational norms--to empirically examine the effect of demographic differences. Whereas the similarity-attraction account suggests that subordinates will perceive their managers as more trustworthy when managers and staff are similar in demographic attributes, the relational norms account proposes that subordinates will perceive their managers as more trustworthy when their demographic differences follow normative expectations. Data collected from a field study of 178 manager-subordinate dyads in Hong Kong and Macau support the relational norms account in terms of education and organizational rank. The authors discuss the theoretical and practical implications of the study.     

Physical and psychological aggression in dating relationships in Spanish university students

The presence of violent behaviors of a psychological and physical nature in dating relations was analyzed in a sample of Spanish university students between 18 and 27 years of age. The results indicate a high prevalence of both kinds of aggression in interpersonal relationships, revealing important typology differences between the sexes. Violent psychological behaviors (characterized by the presence of verbal aggression and coercive and jealous behaviors) and physical aggression were significantly higher in women, though the consequences of physical aggression were worse for the women's health. The implications of the results and their possible relation with more severe violent acts in more stable, emotional relationships are discussed.     

Contracting, prompting, and reinforcing substance use disorder continuing care: a randomized clinical trial.

Although continuing care is strongly related to positive treatment outcomes for substance use disorder (SUD), participation rates are low and few effective interventions are available. In a randomized clinical trial with 150 participants (97% men), 75 graduates of a residential Veterans Affairs Medical Center SUD program who received an aftercare contract, attendance prompts, and reinforcers (CPR) were compared to 75 graduates who received standard treatment (STX). Among CPR participants, 55% completed at least 3 months of aftercare, compared to 36% in STX. Similarly, CPR participants remained in treatment longer than those in STX (5.5 vs. 4.4 months). Additionally, CPR participants were more likely to be abstinent compared to STX (57% vs. 37%) after 1 year. The CPR intervention offers a practical means to improve adherence among individuals in SUD treatment.     

Should we reject the expertise hypothesis?

On the basis of a review of the literature and the results of three experiments with dog experts, Robbins and McKone [Robbins, R. A., & McKone, E. (2006). No face-like processing for objects-of-expertise in three behavioural tasks, Cognition] argue that there is little or no evidence supporting an expertise account of the differences in configural processing that are typically observed between faces and non-face objects. In the spirit of a debate that has become overly polarized, we believe that R&M often emphasized relatively unimportant controversial issues at the expense of bigger, more important questions. We also feel that some of R&M's arguments are rooted in methodological confusions that should be clarified because they have implications beyond this specific debate. In this commentary, we first clarify issues surrounding the proper statistical analysis of the composite paradigm, a methodology that is commonly used to assess configural and holistic effects in both face and non-face objects. We then discuss several theoretical issues that we feel are central to the debate regarding accounts of face-specificity. We also briefly review positive evidence for the correlation between measures of behavioral expertise and neural markers of face-selectivity. Unlike R&M, we believe the positive evidence for expertise effects, both behavioral and neural, greatly outweighs evidence stemming from null results and that it clearly motivates the importance of future work on the role of experience in the specialization of visual cortex.     

Genetic and environmental bases of childhood antisocial behavior: a multi-informant twin study

Genetic and environmental influences on childhood antisocial and aggressive behavior (ASB) during childhood were examined in 9- to 10-year-old twins, using a multi-informant approach. The sample (605 families of twins or triplets) was socioeconomically and ethnically diverse, representative of the culturally diverse urban population in Southern California. Measures of ASB included symptom counts for conduct disorder, ratings of aggression, delinquency, and psychopathic traits obtained through child self-reports, teacher, and caregiver ratings. Multivariate analysis revealed a common ASB factor across informants that was strongly heritable (heritability was .96), highlighting the importance of a broad, general measure obtained from multiple sources as a plausible construct for future investigations of specific genetic mechanisms in ASB. The best fitting multivariate model required informant-specific genetic, environmental, and rater effects for variation in observed ASB measures. The results suggest that parents, children, and teachers have only a partly "shared view" and that the additional factors that influence the "rater-specific" view of the child's antisocial behavior vary for different informants. This is the first study to demonstrate strong heritable effects on ASB in ethnically and economically diverse samples.