The Nervous System
Basic functions and structure:
The nervous system is the body’s communicator straight from the brain. The nervous system’s job is to pull in and sort through internal and external information and send neurotransmitters and neurohormones around the entire body by electrical impulse. Since the nervous system is the main communicator of the body, it exists in and affects the entire body and the entire body affects the nervous system.
The electrical impulse signals need minerals and electrolytes to act as conductors to allow them to buzz through the body. If the body doesn’t have enough electrolytes, the electrical impulses could be slow and the body won’t be able to receive all of the messages that it needs. The minerals in the body come from the bones, which need to be continually replenished by a good diet high in calcium, sodium, and other minerals.
Our nerves function sort of like a wire, they have a coating so that the impulses aren’t released in random places, shocking organs and muscles into function when they don’t need to be. The coating is called a myelin sheath and it is made out of at least 70% fat. Myelin sheaths can become frayed through trauma, if a person isn’t eating enough good fats, or if the body isn’t able to use the fats efficiently. This can be painful and cause the body to react with a stress response. There are herbs that can help repair the myelin sheaths like saint john’s wort and milky oats.
There are two main parts of the nervous system, the Central (CNS) and the Peripheral (PNS).
The CNS is broken down into the brain and spinal cord. The CNS processes incoming information from external sources and controls the body’s reactions to them through the PNS and the endocrine system.
The PNS is broken down into the autonomic nervous system, the somatic nervous system (our chosen muscle movement), and the enteric nervous system (the vagus nerve – digestion/CNS feedback loop).
Our autonomic nervous system controls the things that happen without our active thought like blood pressure, body temperature, bladder emptying, sweating, etc. The autonomic nervous system can be further broken down to the sympathetic system (stress state) and parasympathetic system (resting state)- these two systems control our stress state, which can have a huge impact on our overall health. Because of the serious effects that stress has on the body, this is the part of the nervous system that we spend a lot of time working with.
How the nervous system works:
The brain (CNS) processes information and sends signals to the hypothalamus. The hypothalamus acts as an interface between the CNS and the endocrine system, which uses the PNS (along with the bloodstream) to send messages to different parts of the body.
In the neurocrine system, the electric impulses travel to the end of a nerve cell (axon) and release messages directly into tissues. This is how muscles are told to work and follicles are told to secrete, I think of these messages as direct actions that need to happen quickly.
In the neuroendocrine system, nerves are responsible for releasing hormones directly into the bloodstream, those hormones to travel around the body giving specific messages to their targets. Here, the hypothalamus tells the pituitary gland what the body needs in order to react appropriately to the internal and external environment; the pituitary gland controls the release of the neurosignals that transpire through the body to complete those actions.
We most often talk about how this system is used to regulate stress reactions in the body but it is also the same system that regulates general homeostasis in the body, the reproductive system, metabolism, breastfeeding and many other bodily functions. It is important to note that if the body is dealing with consistent stress, the hypothalamus focuses the pituitary gland on releasing the signals to produce stress hormones (adrenalin/cortisol) instead of the signals to produce the hormones necessary for other bodily functions. Since long-term stress can have such serious impacts on the health of the body and the Western culture has a tendency towards high levels of stress, the neuroendocrine system is important to take into consideration when working with people.
Ohlone Reader – endocrine system