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Lower Gyrification of the Ventromedial Prefrontal Cortex in Posttraumatic Stress Disorder:An ENIGMA-PTSD Study
No full textBACKGROUND: Cortical gyrification involves the formation of folds in the cerebral cortex, coinciding with key neurodevelopmental processes. Its strong correlation with increased cortical surface area and decreased cortical thickness may improve cortical signaling efficiency by decreasing cortico-cortical distance. Differences in brain structure have been found in posttraumatic stress disorder (PTSD), yet few small studies have examined cortical gyrification.METHODS: Gyrification was quantified using FreeSurfer's Local Gyrification Index (lGI), derived from 3-dimensional T1-weighted volumetric brain magnetic resonance imaging in 1876 participants (PTSD n = 789, control n = 1087) across 24 sites from the ENIGMA-PGC (Enhancing Neuro Imaging Genetics through Meta-Analysis and Psychiatric Genomics Consortium) PTSD working group. Using a region of interest-based approach, we fitted a linear mixed-effects model with age (mean = 35.6, SD = 9.23, range = 8-95), sex (female = 967 [52%], male = 909 [48%]), pial surface area, PTSD, and random site effects to test associations between PTSD diagnosis/severity and regional lGI. We examined moderating effects of depression, childhood trauma, age, and sex. RESULTS: PTSD diagnosis and severity were both associated with lower lGI for the right medial orbitofrontal and right rostral anterior cingulate cortices. The interaction of PTSD and age was associated with lower lGI for the rostral middle frontal cortex bilaterally. Contrasting comorbid PTSD and major depressive disorder with the PTSD-only group showed that comorbidity was associated with lower lGI in the left inferior and medial temporal cortices.CONCLUSIONS: Lower lGI, which is associated with impaired signaling efficiency, was observed in the PTSD group compared with the control group for the ventromedial prefrontal cortex, a region that has been strongly implicated in associative fear learning and extinction. It is possible that PTSD accelerates the typical age-associated decline in lGI of the rostral middle frontal cortices.</p
All the World’s a Stage:The Ironic Worlding of "Birds Aren’t Real"
No full textLars de Wildt focuses on the “Birds Aren’t Real” (BAR) conspiracy theory, which claims that birds are government surveillance drones and that the COVID-19 pandemic was a cover for changing their batteries. Drawing on BAR's social media content, parodic in nature, as well as documentaries and legacy media interviews, this chapter argues that BAR is not an outlier in the realm of online conspiracy theories but rather serves as a paradigm for how these theories “play” with truth. De Wildt explores how BAR functions as social media theater, blending memes and marches to create an alternative world in the public sphere, drawing participants into its narrative in the tradition of Boal and Brecht. BAR's performance embodies a voluntary suspension of reality, in line with the playful principles proposed by Huizinga, Caillois, and Sutton-Smith. The chapter concludes that BAR's playful, parodic worlding is representative of how all conspiracy theories blur the line between truth and play, offering alternative hypothetical worlds for people to engage with
A Lifespan Perspective on Mentoring:An Examination of Age-Related Antecedents and Differences in Work Outcomes of Mentoring
No full textConsidering the aging workforce, organizations are increasingly seeking human resources practices that leverage older workers’ skills and knowledge while keeping them engaged at work. Mentoring, defined as a developmental relationship in which a more experienced person supports the professional and personal development of a less experienced person, is widely regarded as a promising HR practice in this context. However, age-based assumptions about mentoring have remained largely unexamined, and both theoretical and empirical research have rarely explored how age-related changes influence mentoring processes and outcomes.This dissertation introduces a lifespan model of workplace mentoring, proposing that older workers may be particularly effective mentors due to well-developed emotional competencies and higher levels of generativity (the motive and behavior to support and guide the next generation). It further suggests that providing mentoring may be especially engaging for older workers because of age-related shifts toward prioritizing emotionally meaningful goals, such as generativity. Paths of the proposed model were tested using different research designs, including a systematic literature review, a meta-analysis, and a dyadic study of supervisors and employees.Overall, the findings provided only limited support for the model. A systematic review indicated that older workers may have well-developed emotional competencies, although effect sizes were generally small. The meta-analysis showed a small positive association between age and generativity. Finally, a study with 154 supervisor–employee dyads revealed no age differences in the associations between mentoring and work engagement, suggesting that both mentors and protégés may benefit from mentoring, independent of age