Crossing the midline of the body with this movement stimulates the300 million nerve cells of the corpus callosum. The corpus callosum is known as the brain? s superhighway.

• 超越身体中线的动作可刺激胼胝体内三亿条轴突纤维,胼胝体（接左右脑的主要路径）称为脑部超级高速公路。