条件反射的建立和消退是生理卫生教学中的重点和难点。为了突破此难点,传统的做法是讲述经典性实验或课前（后）做小鸡啄食条件反射实验等。前者的缺点是不能加强直观;后者的缺点是费时较多,一般一周以上,而且受许多因素限制,多数学校难以开展。为此,我们经多次探索,以蟾蜍为实验材料设计实验,能克服上述缺点,一节课就可完成,几乎不受季节限制,每一个学校都可进行。 一、基本原理 各种无关刺激（如灯光）与非条件刺激（如硫酸）先后作用于动物的过程,称为强化。在强化过程中,高级中枢神经系统内相应两个兴奋灶之间,因兴奋的扩散,较强兴奋灶对弱兴奋灶的吸收作用等,在功能上逐步形成了暂时性接通。此时无关刺激就成为具有信号 The establishment and regression of conditioned reflexes are the key and difficult points in physical health education. In order to overcome this difficulty, the traditional approach is to talk about classic experiments or pre-school (after) chicks feeding condition reflex experiments. The disadvantage of the former is that it cannot be enhanced intuitively; the disadvantage of the latter is that it takes more time, generally more than a week, and is restricted by many factors, and most schools are difficult to carry out. For this reason, we have explored many times and designed experimentation by using Tritium as an experimental material, which can overcome the above shortcomings. A class can be completed, and it is almost independent of the season. Every school can do it. First, the basic principle of a variety of unrelated stimuli (such as light) and non-conditional stimuli (such as sulfuric acid) have a role in the process of animals, known as strengthening. In the process of enhancement, between the corresponding two excitatory foci in the advanced central nervous system, due to the proliferation of excitement, the absorption of weak excitable foci by stronger excitatory foci, etc., a gradual connection was gradually formed in function. At this point, irrelevant stimulation becomes signal