The arterial baroreflex system plays a key role in maintaining the homeostasis of arterial pressure (AP). Changes in AP affect autonomic nervous activities through the baroreflex neural arc, whereas changes in the autonomic nervous activities, in turn, alter AP through the baroreflex peripheral arc. This closed-loop negative feedback operation makes it difficult to identify open-loop dynamic characteristics of the neural and peripheral arcs. Regarding sympathetic AP controls, we examined the applicability of a nonparametric frequency-domain closed-loop identification method to the carotid sinus baroreflex system in anesthetized rabbits. This article compares the results of an open-loop analysis applied to open-loop data, an open-loop analysis erroneously applied to closed-loop data, and a closed-loop analysis applied to closed-loop data. To facilitate the understanding of the analytical method, sample data files and sample analytical codes were provided. In the closed-loop identification, properties of the unknown central noise that modulated the sympathetic nerve activity and the unknown peripheral noise that fluctuated AP affected the accuracy of the estimation results. A priori knowledge about the open-loop dynamic characteristics of the arterial baroreflex system may be used to advance the assessment of baroreflex function under closed-loop conditions in the future.

中文翻译：

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频域中压力反射特性的闭环识别。

动脉压力反射系统在维持动脉压 (AP) 的稳态方面起着关键作用。AP 的变化通过压力反射神经弧影响自主神经活动，而自主神经活动的变化反过来通过压力反射外周弧改变 AP。这种闭环负反馈操作使得难以识别神经和外周弧的开环动态特性。关于交感神经 AP 控制，我们检查了非参数频域闭环识别方法对麻醉兔颈动脉窦压力反射系统的适用性。本文比较了应用于开环数据的开环分析、错误地应用于闭环数据的开环分析以及应用于闭环数据的闭环分析的结果。为了便于理解分析方法，提供了样品数据文件和样品分析代码。在闭环识别中，调制交感神经活动的未知中枢噪声和波动AP的未知外周噪声的特性影响了估计结果的准确性。关于动脉压力反射系统的开环动态特性的先验知识可用于在未来推进闭环条件下压力反射功能的评估。调制交感神经活动的未知中枢噪声和波动 AP 的未知外周噪声的特性影响了估计结果的准确性。关于动脉压力反射系统的开环动态特性的先验知识可用于在未来推进闭环条件下压力反射功能的评估。调制交感神经活动的未知中枢噪声和波动 AP 的未知外周噪声的特性影响了估计结果的准确性。关于动脉压力反射系统的开环动态特性的先验知识可用于在未来推进闭环条件下压力反射功能的评估。