Ascending Pathways for the Periaqueductal Gray

描述（由申请人提供）：该提案的广泛，长期目标是阐明决定情绪和影响的神经系统的组织。这项研究的主要目的是确定猴中脑导水管周围灰质（PAG）可能影响皮质功能的轴突通路。PAG作为产生情绪表达的关键组成部分，PAG的不同细分协调对不同类型压力的不同情绪反应。PAG广泛投射到中线/板内丘脑核（ILN），这代表了PAG可能影响皮质功能的一个可能途径。在大鼠中，单个ILN投射到大脑皮层的限定区域，该区域对应于灵长类动物的眼眶和内侧前额叶皮层（OMPFC），这是一个被认为参与最高水平情绪处理的皮层区域。虽然这些通往大脑皮层的通路在大鼠中最为人所知，但OMPFC在猴子中更为发达和更为人所知。特别是，灵长类动物的OMPFC可以分为不同的功能网络，假设以subserve不同的组件的情绪。据推测，来自PAG分支的上行通路将与这两个网络进行差异化的相互作用，反映了它们在对压力的情绪反应中的不同作用。清楚地了解这一通路在灵长类动物中是如何联系的，可能会让我们深入了解精神疾病的神经基础，如重度抑郁症和焦虑症，这些疾病的特征是对压力的适应不良情绪反应。

DESCRIPTION (provided by applicant): The broad, long-term goal of this proposal is to elucidate the organization of neural systems that determine mood and affect. The primary objective of the proposed research is to define in monkeys the axonal pathways by which the midbrain periaqueductal gray (PAG) may influence cortical function. The PAG as a critical component in generating emotional expression, and distinct subdivisions of the PAG coordinate distinct emotional reactions to different types of stress. The PAG projects extensively to the midline/intralaminar thalamic nuclei (ILN), which represents one likely pathway through which the PAG may influence cortical function. In rats, individual ILN project to circumscribed areas of the cerebral cortex that correspond to the primate orbital and medial prefrontal cortex (OMPFC), a cortical area thought to be involved in the highest levels of emotional processing. Although these pathways to the cerebral cortex are best known in rats, the OMPFC is much more developed and better known in monkeys. In particular, the primate OMPFC can be divided into distinct functional networks that are hypothesized to subserve different components of emotion. It is hypothesized that the ascending pathways from subdivisions of the PAG will interact differentially with the two networks, reflecting their differential role in emotional reactions to stress. A clear understanding of how this pathway is linked in primates may provide insight into the neural basis of psychiatric illnesses such as major depression and anxiety disorders, which are characterized by maladaptive emotional responses to stress.