Perceived threat predicts the neural sequelae of combat stress

Exposure to severe stressors increases the risk for psychiatric disorders in vulnerable individuals, but can lead to positive outcomes for others. However, it remains unknown how severe stress affects neural functioning in humans and what factors mediate individual differences in the neural sequelae of stress. The amygdala is a key brain region involved in threat detection and fear regulation, and previous animal studies have suggested that stress sensitizes amygdala responsivity and reduces its regulation by the prefrontal cortex. In this study, we used a prospective design to investigate the consequences of severe stress in soldiers before and after deployment to a combat zone. We found that combat stress increased amygdala and insula reactivity to biologically salient stimuli across the group of combat-exposed individuals. In contrast, its influence on amygdala coupling with the insula and dorsal anterior cingulate cortex was dependent on perceived threat, rather than actual exposure, suggesting that threat appraisal affects interoceptive awareness and amygdala regulation. Our results demonstrate that combat stress has sustained consequences on neural responsivity, and suggest a key role for the appraisal of threat on an amygdala-centered neural network in the aftermath of severe stress

Chronic Stress Induces Sex-Specific Alterations in Methylation and Expression of Corticotropin-Releasing Factor Gene in the Rat

Contains fulltext : 91627.pdf (publisher's version ) (Open Access

New horizons for future research - Critical issues to consider for maximizing research excellence and impact.

We live in an era in which the pace of research and the obligation to integrate new discoveries into a field's conceptual framework are rapidly increasing. At the same time, uncertainties about resources, funding, positions and promotions, the politics of science, publishing (the drive to publish in so-called high-impact journals) and many other concerns are mounting. To consider many of these phenomena in depth, a meeting was recently convened to discuss issues critical to conducting research with an emphasis on the neurobiology of metabolism and related areas. Attendees included a mix of senior and junior investigators from the United States, Latin America, and Western Europe, representing several relevant disciplines. Participants were initially assigned to small groups to consider specific questions in depth, and the results of those deliberations were then presented and discussed over several plenary sessions. Although there was spirited discussion with sometimes differing opinions on some issues, in general there was good consensus among individuals and the various groups. While the discussions were wide-ranging, we have condensed the topics into three (albeit often overlapping) major areas: 1) General research issues applicable to multiple areas of translational research; for instance, animal models, sex and gender differences, examples of emerging technologies, as well as the issue of data reproducibility and related topics. 2) Funding issues, such as how to secure industry funding without compromising research direction or academic integrity, and the training of students and fellows, with a focus on how to optimally prepare trainees for the diverse potential career paths available. 3) Finally, specific research topics of interest were discussed, including whether peptides or other signaling compounds, or specific brain areas, have “thematic functions” or the challenges associated with investigating the function of G-protein-coupled receptors (GPCR) in the brain