Gander P H, Kronauer R E, Czeisler C A, Moore-Ede M C
Am J Physiol. 1984 Sep;247(3 Pt 2):R427-44. doi: 10.1152/ajpregu.1984.247.3.R427.
In our two-oscillator model for the human circadian timing system, the effect of an environmental synchronizing cycle (zeitgeber) is determined by the periods of the two oscillators and of the zeitgeber and by the zeitgeber strength. The oscillators x and y are postulated to regulate the core temperature and rest-activity rhythms, respectively. From published examples of experiments in which human subjects were exposed to artificial zeitgebers, it is possible to derive estimates of the periods of the core temperature and/or the rest-activity rhythms and the zeitgeber. Two strengths of zeitgeber input to the model that correspond to two of the common zeitgeber regimes used in human entrainment studies have now been elucidated. Thus specific model simulations can be generated for each of the available examples of entrainment of human subjects by artificial zeitgebers. Such simulations indicate that the model can reproduce, with remarkable subtlety, the types of full and partial entrainment observed experimentally. The model is thus demonstrated to accommodate the period and phase control of endogenous rhythms by environmental zeitgebers, which is a crucial functional attribute of circadian timing systems.
在我们关于人体昼夜节律计时系统的双振荡器模型中，环境同步周期（授时因子）的作用由两个振荡器、授时因子的周期以及授时因子强度决定。假定振荡器x和y分别调节核心体温和静息 - 活动节律。从已发表的人体受试者暴露于人工授时因子的实验示例中，可以得出核心体温和/或静息 - 活动节律以及授时因子周期的估计值。现已阐明模型中授时因子输入的两种强度，它们对应于人体同步研究中使用的两种常见授时因子模式。因此，对于人工授时因子使人体受试者同步的每个可用示例，都可以生成特定的模型模拟。此类模拟表明，该模型能够极其精细地重现实验中观察到的完全同步和部分同步类型。因此，该模型被证明能够适应环境授时因子对内生节律的周期和相位控制，这是昼夜节律计时系统的关键功能属性。
