Hallowitz R A, MacLean P D
Brain Res. 1977 Jul 15;130(2):271-86. doi: 10.1016/0006-8993(77)90275-x.
As part of an attempt to clarify the nature of inputs to the limbic cortex, the thalamic intralaminar and juxtalaminar nuclei were explored for unit responses to vagal volleys in awake, sitting squirrel monkeys. Vagal shocks elicited responses of a large percentage of units in the anterior medial, paracentral, lateral dorsal, and lateral, and medial dorsal nuclei, as well as in part of the ventral lateral nucleus adjacent to the paracentral. Responsive units showed either initial excitation or initial inhibition. As in the preceding study on the cingulate and supracingulate cortex, there were two main types of initially excited units: type 1 responded with a discharge of 1-3 spikes at relatively short and constant latencies, while type 2 units were characterized by a burst of 3-14 spikes at longer and more variable latencies. Although the findings were compatible with the hypothesis that the anterior and paracentral nuclei transmit vagal impulses to the cingulate and supracingulate cortex, an analysis of latencies suggested that a more rapidly conducting pathway(s) accounts for latencies as short as 12 msec of some cingulate units. Twenty-eight percent of 367 units in the medial dorsal nucleus responded to vagal volleys. This finding gives substantial support to the traditional view that the medial dorsal nucleus transmits interoceptive information to limbic and neocortical areas of the orbitofrontal region.
作为明确边缘皮质输入性质尝试的一部分，研究了丘脑板内核和板旁核，以观察清醒、坐姿松鼠猴对迷走神经冲动的单位反应。迷走神经电击在以下核团中引发了很大比例单位的反应：前内侧核、中央旁核、背外侧核、外侧核、内侧背核，以及中央旁核附近的部分腹外侧核。反应性单位表现出初始兴奋或初始抑制。与之前对扣带回和扣带回上皮质的研究一样，最初兴奋的单位主要有两种类型：1型在相对较短且恒定的潜伏期以1 - 3个峰电位放电做出反应，而2型单位的特征是在较长且更可变的潜伏期出现3 - 14个峰电位的爆发。尽管这些发现与前核和中央旁核将迷走神经冲动传递到扣带回和扣带回上皮质的假设相符，但对潜伏期的分析表明，一条传导速度更快的通路可以解释一些扣带回单位短至12毫秒的潜伏期。内侧背核中367个单位中有28%对迷走神经冲动有反应。这一发现为内侧背核将内感受信息传递到眶额叶区域的边缘和新皮质区域这一传统观点提供了有力支持。
