Your nervous system is divided into 2 main components, the “central nervous system” and the “peripheral nervous system”.
What is the nervous system?
The nervous system is your body’s main control system. It is responsible for your movements and senses, your thoughts and memories, and your many life support systems. It allows you to monitor, and interact with, your internal and external environments.
What is the central nervous system?
The central nervous system is made up of your brain and spinal cord. The brain is your central processing unit, responsible for controlling all of your bodily functions and actions. It is an incredibly complex structure composed of tens of billions of specialized nerve cells, each communicating with thousands of others. The spinal cord is responsible for getting the brain’s movement commands out to your body, and for bringing information back to your brain.
What is the peripheral nervous system?
The peripheral nervous system is the huge network of nerves that lie outside your brain and spinal cord. It connects your brain to your limbs and organs, and is divided into 2 parts. One part controls your voluntary movements and carries sensory information, and the other controls involuntary movements such as your heart beat and pupil dilation.
What are neurons?
Neurons are the primary cells that make up your nervous system, and they generate up to 2,000 nerve pulses per second that send information from the brain to every other part of your body, and back again. Neurons are made up of a cell body with nerve fibers extending out to other cells. Healthy nerve fibers are similar to electrical cables, and have an insulating layer around them called “myelin”.
When a neuron sends a pulse down its fiber, chemical signals called “neurotransmitters” are released from the other end. These neurotransmitters act as messengers to other cells, maybe telling your muscles to contract, or communicating with other neurons.
Each neuron in the brain has connections with as many as 10,000 other neurons. In this way, they are able to form extremely complex networks which can perform amazing feats such as your detailed color vision, allowing you to talk and run, or storing thousands of memories.
The energy required to send all of these pulses, release neurotransmitters and maintain the general health of our neurons is huge, and your brain alone can use as much as 20% of your entire body’s energy supply. This is why your neurons are densely packed with “mitochondria”, the energy-producing “cellular batteries” which power cells. Mitochondria combine the food you eat with the air you breathe, and turn it into the energy that your cells need to function and grow.
Your neurons are therefore highly dependent on your mitochondria being as healthy as possible and performing as efficiently as they can. However, as we age or when we get ill, our mitochondria start to decline and things can start to go wrong.
Click here to continue to part 2 'Neurological Disorders & Our Mitochondria'