There are two communication systems in the brain
The Nervous System and the Endocrine System
Nervous System: extensive network of nerve cells that carry messages in pulses of electrical and chemical energy throughout the body. This is the network that first comes to your rescue by accelerating you heart and tensing your muscles for action.
Endocrine System: a slower acting communication network that sends a follow up message that supports and sustains that support the emergency response initiated by the nervous system. They send these messages through chemical messengers known as hormones.
The cooperation between the endocrine and nervous system is at the hypothalamus.
The Neuron: The Building Block of the Nervous System
The nervous system is made up of nerve cells called neurons.
Neuron: a nerve cell that receives processes and transmits information to other cells. The speeds in which they do so are within fractions of seconds.
There are three different types of neurons, varying in size and shapes but have similar structure.
Sensory Neurons (Afferent) - they carry information from the sense organs towards the brain. They essentially act like one-way streets.
Ex: when you test water temperature in your shower with your hand, sensory neurons carry the message towards the brain.
Motor Neurons (Efferent) – also one-way streets but they carry information away from the brain to muscles, organs and glands.
Ex: in the shower, the motor neurons deliver the message from the brain that tells your hand how much to move the shower control knob.
Interneurons: because motor and sensory neurons do not interact, the interneurons are the neurons that relay messages between motor, sensory and other interneurons.
How Neurons Work
Dendrites: receive incoming messages. They are branched fibers acting like a net to collect messages received by direct stimulation
Soma: the dendrites pass on these