**4. The neurology of the swallow**

#### **4.1 The phases of the swallow**

The four phases of the swallowing process described above involve 148 muscles and six cranial nerves. Of course, the muscular activities described are not separate from the nerve and brain activity that control them, the entire neurophysiology [25] of the swallowing process must work correctly. Understanding how is fundamental to appreciating how a dysfunctional swallow can be treated.

**Figure 5** illustrates four important areas of the brain [25].

**Figure 5.** *The brain.*

