Dampney Roger A L
School of Medical Sciences (Physiology) and Bosch Institute, University of Sydney, New South Wales, Australia
Am J Physiol Regul Integr Comp Physiol. 2015 Sep;309(5):R429-43. doi: 10.1152/ajpregu.00051.2015. Epub 2015 Jun 3.
Actual or potentially threatening stimuli in the external environment (i.e., psychological stressors) trigger highly coordinated defensive behavioral responses that are accompanied by appropriate autonomic and respiratory changes. As discussed in this review, several brain regions and pathways have major roles in subserving the cardiovascular and respiratory responses to threatening stimuli, which may vary from relatively mild acute arousing stimuli to more prolonged life-threatening stimuli. One key region is the dorsomedial hypothalamus, which receives inputs from the cortex, amygdala, and other forebrain regions and which is critical for generating autonomic, respiratory, and neuroendocrine responses to psychological stressors. Recent studies suggest that the dorsomedial hypothalamus also receives an input from the dorsolateral column in the midbrain periaqueductal gray, which is another key region involved in the integration of stress-evoked cardiorespiratory responses. In addition, it has recently been shown that neurons in the midbrain colliculi can generate highly synchronized autonomic, respiratory, and somatomotor responses to visual, auditory, and somatosensory inputs. These collicular neurons may be part of a subcortical defense system that also includes the basal ganglia and which is well adapted to responding to threats that require an immediate stereotyped response that does not involve the cortex. The basal ganglia/colliculi system is phylogenetically ancient. In contrast, the defense system that includes the dorsomedial hypothalamus and cortex evolved at a later time, and appears to be better adapted to generating appropriate responses to more sustained threatening stimuli that involve cognitive appraisal.
外部环境中实际存在的或潜在的威胁性刺激（即心理应激源）会触发高度协调的防御行为反应，并伴有相应的自主神经和呼吸变化。如本综述中所讨论的，几个脑区和神经通路在维持对威胁性刺激的心血管和呼吸反应中起主要作用，这些刺激可能从相对轻微的急性唤醒刺激到更持久的危及生命的刺激不等。一个关键区域是背内侧下丘脑，它接收来自皮层、杏仁核和其他前脑区域的输入，并且对于产生对心理应激源的自主神经、呼吸和神经内分泌反应至关重要。最近的研究表明，背内侧下丘脑还从中脑导水管周围灰质的背外侧柱接收输入，这是另一个参与应激诱发的心肺反应整合的关键区域。此外，最近的研究表明，中脑丘中的神经元可以对视觉、听觉和躯体感觉输入产生高度同步的自主神经、呼吸和躯体运动反应。这些丘神经元可能是皮层下防御系统的一部分，该系统还包括基底神经节，并且非常适合对需要立即做出刻板反应且不涉及皮层的威胁做出反应。基底神经节/丘系统在系统发育上很古老。相比之下，包括背内侧下丘脑和皮层的防御系统进化得较晚，并且似乎更适合对涉及认知评估的更持续的威胁性刺激产生适当的反应。
