Breathing is primarily controlled by the autonomic nervous system, which is also known as the involuntary nervous system.
The Autonomic Nervous System and Breathing
The autonomic nervous system manages many of the body's functions without conscious thought. Here's how it relates to breathing:
- Automatic Regulation: You don't need to consciously tell yourself to breathe; this system does it automatically.
- Parasympathetic System's Role: The parasympathetic system, a division of the autonomic nervous system, plays a role in slowing your breathing rate.
- It also causes your bronchial tubes to narrow, impacting airflow.
- The system also widens pulmonary blood vessels.
Key Components of Breathing Control
While the autonomic nervous system is the primary controller, there are other components involved:
- Brain Stem: The brain stem (particularly the medulla oblongata and pons) houses the respiratory control center. It receives signals from the body, like changing CO2 or oxygen levels, and adjusts breathing accordingly.
- Chemoreceptors: Located in the brain and large arteries, these receptors monitor oxygen and carbon dioxide levels and signal the respiratory center to adjust breathing.
- Stretch Receptors: Found in the lungs, these receptors signal when the lungs are inflated to a certain point, helping to regulate breathing depth and prevent over-inflation.
Practical Examples
- When you exercise, the autonomic nervous system increases your breathing rate to provide more oxygen and remove more carbon dioxide.
- During sleep, the autonomic nervous system regulates breathing at a slower, relaxed rate.
- When you hold your breath, you can temporarily override the automatic control, but the autonomic nervous system eventually will initiate breathing.
Summary
In summary, while your breathing generally requires no conscious thought, it is regulated by the autonomic nervous system. The parasympathetic branch of this system slows your breathing rate, constricts bronchial tubes and dilates pulmonary blood vessels.
