Behavioural Endocrinology and Sexual Dimorphism of Brain and Behaviour

像身体的其他部分一样，由于性激素的作用，神经系统呈现出男性或女性的形式和功能。探索这些差异有助于我们了解神经系统的功能、专业化和自我重塑。为了研究激素、神经系统和行为之间的相互关系，我们提出了三个基本问题：(1)性激素如何作用于神经结构，使它们呈现男性或女性的形态？我们正在进行的研究项目集中在脊髓、脑干和小脑的模型系统上，我们之前已经将这些系统与男性性相关行为和性类固醇睾丸激素的作用联系起来。在拟议的研究中，我们将探索睾酮对性环境中活跃的交际行为的神经和遗传控制的影响。此外，我们将绘制先前未被充分研究的男性性回路的脑干成分的性别差异图。其他的研究建立在我们的工作基础上，表明增塑剂双酚A （BPA）改变了脊髓中性类固醇敏感神经元的结构——接下来，我们将研究对其他大脑区域的影响，并检查BPA替代物质的影响，这些物质似乎具有类似类固醇的作用。我们还将研究这些物质对大脑结构的影响如何通过表观遗传修饰传递给后代。(2)睾酮等雄激素如何调节行为过程？几个拟议的实验探讨雄激素在产生超声发声中的作用，超声发声是大鼠的一种重要的交流行为。我们感兴趣的是它们的信号质量，以及由激素暴露决定的社会和性发展的关系。在其他工作中，我们计划彻底探索增塑剂通过模仿类固醇改变大鼠认知、情感和性行为中正常性别差异表达的新方法。(3)相反，行为和社会暗示如何改变性激素？主要针对人类，我们感兴趣的是生态上重要的环境线索——如优势竞争、关系、社会环境和生殖机会——如何引起男性和女性睾酮释放的变化。据推测，这种机制是一种古老的适应机制，它协调生理和神经机制与环境机会。拟议的研究探讨了内分泌对社会输入的反应，如竞争、团队合作、社会排斥和配偶刺激。我们还将系统地评估性别认同在决定社会内分泌反应性方面的影响，以及更传统的性别差异。*** *** *** **

Like the rest of the body, the nervous system takes on a male or female form and function due to the actions of sex hormones. Exploring these differences helps us learn about how the nervous system functions, specializes and remodels itself. To study the reciprocal relationships between hormones, the nervous system, and behaviour, we ask three basic questions: (1) How do sex hormones act on neural structures to cause them to take on male or female form? Our on-going research program focuses on model systems in the spinal cord, brainstem, and cerebellum, that we have previously linked to masculine sex-related behaviour and the actions of the sex steroid testosterone. In proposed research we will explore testosterone's influence on neural and genetic control of communicative behaviours active in sexual contexts. Additionally, we will map sex differences in previously understudied brainstem components of the male sexual circuitry. Other studies build on our work showing that the plasticizer bisphenol A (BPA) alters the structure of sex steroid-sensitive neurons in the spinal cord – next, we will study effects in additional brain regions, and examine effects of BPA replacement substances that appear to have steroid-like actions of their own. We will also study how the effects of these substances on the structure of the brain are passed on to subsequent generations through epigenetic modification. (2) How do androgens like testosterone regulate behavioural processes? Several proposed experiments probe the role of androgens in the production of ultrasonic vocalizations, an important communicative behaviour in rats. We are interested in their signalling qualities, and relation to social and sexual development as determined by hormone exposure. In other work, we plan to thoroughly explore novel ways in which plasticizers, by mimicking steroids, alter the expression of normal sex differences in cognitive, emotional, and sexual behaviours in rats. (3) Reversing the relationship, how do behaviours and social cues alter sex hormones? Turning mostly to humans, we are interested in how ecologically-important environmental cues – like dominance competitions, relationships, social settings, and reproductive opportunities – provoke changes in testosterone release in men and women. Presumably, this mechanism is an ancient adaptation that coordinates physiology and neural mechanisms with environmental opportunities. Proposed studies probe endocrine reactivity in response to social inputs likes competition, teamwork, social exclusion, and mate stimuli. We will also systematically evaluate the impact of gender identity in determining social endocrine reactivity, alongside more traditional sex differences.*** *** *** **