cephalic phase

例句：

1. 1. The study of the cephalic phase is crucial for understanding the development of language.
   研究头期阶段对于理解语言的发展至关重要。
2. 2. The cephalic phase is characterized by a rapid increase in the number of neurons in the brain.
   头期阶段的特点是大脑中神经元数量的迅速增加。
3. 3. During the cephalic phase, the body undergoes significant changes in response to stress.
   在头期阶段，身体会经历重大变化以应对压力。