The highly complex and organized organ system in humans is the nervous system. It comprises of the spinal cord, sensory organs, brain and the nerves connecting all these with each and every part of the body. Together, these organs are in charge of control of the body and communication within various organs.
The mind and spinal cord constitute the control center known as the Central Nervous System (CNS), where data is assessed and decisions are made. The sensory organs and nerves of the Peripheral Nervous System (PNS) check conditions inside and outside of the body and send this data to the CNS.
The CNS and the PNS together transmit and process sensory data and regulate body functions. They get information from the sensory organs and from nerves in the body, process the data, and send proper commands.
Nerve pathways of the PNS convey the incoming and outgoing data. Twelve sets of cranial nerves link the mind to eyes, ears, and other sensory organs and to head and neck muscles.
31 sets of spinal nerves stretch out from the spinal cord to tissues of the thorax, abdomen and lower body. The nerves are responsible for transmitting data and sending motor commands.
Every sensory tissue incorporates cells called neurons. Neurons are charged cells which lead electrical signals to pass data throughout the body.
A neuron comprises a cell body, dendrites, and an axon terminal. When an outgoing signal is created, it contacts the axon terminal and goes to the following neuron or target cell. This conductive ability sends data all over nerve pathways and through the central nervous system at unimaginable speed. Some 100 billion neurons give the brain its tremendous processing power.
Nervous system transmits data as electrical signals through neurons. As these signal reach the end of neurons, they release the chemicals called neurotransmitters. They travel across synapses which are spaces between neurons and body tissues.
Neurotransmitters are 2 types − Excitatory and Inhibitory. Excitatory transmitters invigorate electrical signals in different neurons and encourage reactions from body cells. Inhibitory transmitters debilitate signals and cell reactions. Through these chemicals, the sensory system directs the action of muscles, organs, and its own nerve pathways.
The spinal cord is a prolonged cylinder of neuron cell bodies, packs of axons secured by connective tissue and bone.
It joins with the brain at the medulla oblongata and keeps running down the vertebral section. The spinal cord belongs to the central nervous system.
Sensory data and motor control travel to and from the brain. The spinal cord can impart a reflex command without bothering the brain.
The nervous system performs more than the transfer of data and process commands.
The limbic framework creates two combined rings inside the brain, comprising of the hippocampus, the amygdala, the cingulate gyrus, and the dentate gyrus, along with various structures and tracts.
Similarly, as with other brain sections, the limbic system is associated with different sensory system capacities and levels of activity. The structures of the limbic system are involved in memory, emotion, motivation, and learning.