What Controls Your Breathing?
A respiratory control center at the base of your
brain controls your breathing. This center sends ongoing signals down your
spine and to the nerves of the muscles involved in breathing.
These signals ensure your breathing muscles contract
(tighten) and relax regularly. This allows your breathing to happen
automatically, without you being aware of it.
To a limited degree, you can change your breathing
rate, such as by breathing faster or holding your breath. Your emotions also
can change your breathing. For example, being scared or angry can affect your
breathing pattern.
Your breathing will change depending on how active
you are and the condition of the air around you. For example, you need to
breathe more often when you do physical activity. In contrast, your body needs
to restrict how much air you breathe if the air contains irritants or
toxins.
To adjust your breathing to changing needs, your
body has a number of sensors in your brain, blood vessels, muscles, and
lungs.
Sensors in the brain and in two major blood vessels
(the carotid (ka-ROT-id) artery and the aorta) detect carbon dioxide or oxygen
levels in your blood and change your breathing rate as needed.
Sensors in the airways detect lung irritants. The
sensors can trigger sneezing or coughing. In people who have
asthma,
the sensors may cause the muscles around the airways in the lungs to contract.
This makes the airways smaller.
Sensors in the alveoli (air sacs) detect a buildup
of fluid in the lung tissues. These sensors are thought to trigger rapid, shallow
breathing.
Sensors in your joints and muscles detect movement
of your arms or legs. These sensors may play a role in increasing your
breathing rate when you're physically active. |