Following sexual maturity, females disproportionately have higher rates of posttraumatic stress disorder (PTSD) and experience greater symptom severity and chronicity as compared with males. This observation has led many to examine sex differences in PTSD risk factors. Though relatively few, these studies reveal that the root causes of PTSD sex differences are complex, and partly represent interactions between sex-specific nonbiological and biological risk factors, which differentially shape PTSD vulnerability. Moreover, these studies suggest that sex-specific PTSD vulnerability is partly regulated by sex differences in fear systems. Fear, which represents a highly conserved adaptive response to threatening environmental stimuli, becomes pathological in trauma- and stress-based psychiatric syndromes, such as PTSD. Over the last 30 years, considerable progress has been made in understanding normal and pathological molecular and behavioral fear processes in humans and animal models. Thus, fear mechanisms represent a tractable PTSD biomarker in the study of sex differences in fear. In this review, we discuss studies that examine nonbiological and biological sex differences that contribute to normal and pathological fear behaviors in humans and animal models. This, we hope, will shed greater light on the potential mechanisms that contribute to increased PTSD vulnerability in females.

中文翻译：

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恐惧和创伤后应激障碍的性别差异机制

性成熟后，与男性相比，女性的创伤后应激障碍 (PTSD) 发生率更高，并且症状的严重程度和慢性程度更高。这一观察导致许多人检查 PTSD 风险因素的性别差异。虽然相对较少，但这些研究表明 PTSD 性别差异的根本原因是复杂的，部分代表了性别特定的非生物和生物风险因素之间的相互作用，这些因素对 PTSD 脆弱性的影响不同。此外，这些研究表明，特定性别的 PTSD 脆弱性部分受恐惧系统中的性别差异的调节。恐惧代表对威胁性环境刺激的高度保守的适应性反应，在基于创伤和压力的精神综合征（如 PTSD）中变得病态。在过去的 30 年里，在理解人类和动物模型中的正常和病理分子和行为恐惧过程方面取得了相当大的进展。因此，在恐惧的性别差异研究中，恐惧机制代表了一种易于处理的 PTSD 生物标志物。在这篇综述中，我们讨论了检查非生物和生物性别差异的研究，这些差异有助于人类和动物模型中的正常和病理性恐惧行为。我们希望，这将进一步阐明导致女性 PTSD 脆弱性增加的潜在机制。我们讨论了检查非生物和生物性别差异的研究，这些差异有助于人类和动物模型中的正常和病理性恐惧行为。我们希望，这将进一步阐明导致女性 PTSD 脆弱性增加的潜在机制。我们讨论了检查非生物和生物性别差异的研究，这些差异有助于人类和动物模型中的正常和病理性恐惧行为。我们希望，这将进一步阐明导致女性 PTSD 脆弱性增加的潜在机制。