Evidence for the thalamic targets of the medial hypothalamic defensive system mediating emotional memory to predatory threats

Previous studies from our laboratory have documented that the medial hypothalamic defensive system is critically involved in processing actual and contextual predatory threats, and that the dorsal premammillary nucleus (PMd) represents the hypothalamic site most responsive to predatory threats. Anatomical findings suggest that the PMd is in a position to modulate memory processing through a projecting branch to specific thalamic nuclei, i.e., the nucleus reuniens (RE) and the ventral part of the anteromedial nucleus (AMv). In the present study, we investigated the role of these thalamic targets in both unconditioned (i.e., fear responses to predatory threat) and conditioned (i.e., contextual responses to predator-related cues) defensive behaviors. During cat exposure, all experimental groups exhibited intense defensive responses with the animals spending most of the time in the home cage displaying freezing behavior. However, during exposure to the environment previously associated with a cat, the animals with combined RE + AMv lesions, and to a lesser degree, animals with single AMv unilateral lesions, but not animals with single RE lesions, presented a reduction of contextual conditioned defensive responses. Overall, the present results provide clear evidence suggesting that the PMd’s main thalamic targets (i.e., the nucleus reuniens and the AMv) seem to be critically involved in the emotional memory processing related to predator cues.     

A Finer Grained Approach to Psychological Capital and Work Performance

Purpose

Psychological capital is a set of personal resources comprised by hope, efficacy, optimism, and resilience, which previous research has supported as being valuable for general work performance. However, in today’s organizations, a multidimensional approach is required to understanding work performance, thus, we aimed to determine whether psychological capital improves proficiency, adaptivity, and proactivity, and also whether hope, efficiency, resilience, and optimism have a differential contribution to the same outcomes. Analyzing the temporal meaning of each psychological capital dimension, this paper theorizes the relative weights of psychological capital dimensions on proficiency, adaptivity, and proactivity, proposing also that higher relative weight dimensions are helpful to cope with job demands and perform well.

Methodology

Two survey studies, the first based on cross-sectional data and the second on two waves of data, were conducted with employees from diverse organizations, who provided measures of their psychological capital, work performance, and job demands. Data was modeled with regression analysis together with relative weights analysis.

Findings

Relative weights for dimensions of psychological capital were supported as having remarkable unique contributions for proficient, adaptive, and proactive behavior, particularly when job demands were high.

Originality/Value

We concluded that organizations facing high job demands should implement actions to enhance psychological capital dimensions; however, those actions should focus on the specific criterion of performance of interest.

     

Effects of aging on action-intentional programming

Background: Action-intentional programs control “when” we initiate, inhibit, continue, and stop motor actions. The purpose of this study was to learn if there are changes in the action-intentional system with healthy aging, and if these changes are asymmetrical (right versus left upper limb) or related to impaired interhemispheric communication. Methods: We administered tests of action-intention to 41 middle-aged and older adults (61.9 ± 12.3 years). Results: Regression analyses revealed that older age predicted a decrement in performance for tests of crossed motor response inhibition as well as slower motor initiation with the left hand. Conclusion: Changes in action-intention with aging appear to be related to alterations of interhemispheric communication and/or age-related right hemisphere dysfunction; however, further research is needed to identify the mechanisms for age-related changes in the brain networks that mediate action-intention.     

Social Support as a School Victimisation Risk Factor

This study examined three sources of social support, peer groups, school and parents, and their impact on the risk of relational, verbal and physical bullying victimization in a representative sample of secondary school adolescents of Talavera de la Reina (Spain). Correlation analysis was used to establish associations and regression analysis in order to confirm the independent effect of each social support type with victimization. The results showed that low social support perception from peers, school and parents increased the risk of relational, verbal and physical bullying victimization. Additionally, the perception of lower parental social support increased the likelihood of relational and verbal bullying victimization, while the hypothesis that low perception of parental social support entailed a higher risk for physical victimization was not confirmed. These findings are discussed in light of previous studies.     

Stress assessment during adolescence: Psychometric properties and measurement invariance of the Student Stress Inventory-Stress Manifestations across gender and age

The main purpose of this study was to analyze the psychometric properties and measurement invariance across gender and age of the Student Stress Inventory-Stress Manifestations (SSI-SM) scores in a large sample of adolescents. The sample was comprised by a total of 1108 students (482 were male), with a mean age of 14.61 years (SD = 1.71). The results indicated that the SSI-SM scores presented adequate psychometric properties from both classical test theory and Item Response Theory (IRT). Confirmatory factorial analysis (CFA), showed that both the bifactor model and a three-factor model (emotional, physiological, and behavioural) were adequate. Multi-group CFA showed that the three-factor model had strong measurement invariance across gender and age. Statistically significant differences in gender were found between latent means as well as raw scores of SSI-SM. Ordinal alpha was .78 for Physiological, .90 for the Emotional, and .79 for the Behavioural subscales. Using IRT, the SSI-SM provides more accuracy information at the medium level of the latent trait. SSI-SM subscales were associated with emotional and behavioural problems. These results provided new sources of validity evidence of the SSI-SM scores in adolescents from general population. The SSI-SM appears to be a useful, brief, and easy to administrate self-report instrument for the screening of stress manifestations at school and educational settings.     

The Influence of Arbitrary Breakpoints on Judgments of Maximum Output

Consumers often wonder about the product's maximum output: the highest rotation speed of a blender or the best printing quality of a printer. We examine how the number of levels (e.g., a blender with 3 vs. 7 speeds) influences judgments of maximum product output. Objectively speaking, the number of levels is no more than a set of breakpoints in an already predetermined continuum from the product's minimum to maximum output. Nevertheless, because of the ubiquitous association between number of breakpoints and quantity in daily life, consumers do not simply view more levels as a signal of greater precision (i.e., giving consumers more control over the possible outputs). They also incorrectly believe that the product has greater power (i.e., a higher maximum output), even when such an inference is in conflict with diagnostic attribute information (e.g., watts). A series of five studies documents the phenomenon, its asymmetric nature, and its boundary conditions. Reliance on the inaccurate “more levels, more power” lay theory weakens when participants consider a reduction rather than an increase in number of levels, and it disappears when the consumer is presented with an explicit relationship between each level and its corresponding output value (e.g., level 4:400 W).     

Effects of parental involvement in teacher training1

Successful intervention programs in school settings are characterized by individualized instruction, teacher training and parental involvement. A program including those characteristics was implemented for the development of competence in Mexican sixth-graders from eight classrooms. A course in child development was offered in the control classrooms for teachers alone, in the experimental classrooms for teachers and parents together. The idea of developing children's competence by setting a common superordinate goal for parents and teachers does receive modest but real support. The reaction of the community to the program demonstrates the responsiveness and resourcefulness of low income families when presented with an opportunity to act and act effectively in behalf of their children's development.