The human brain is the single most complex object studied to date. The brain is the boss of the human body. Our experience and behavior are shaped by our central nervous system. Neurotransmitters play a vital role in regulating our emotions and mood.
But how do they influence us?
How mind Works and communicate?
Let’s know in simple terms :
Philosopher Descartes proposed that the mind and body are two separate entities and both influence each other. Some philosophers proposed our whole body is a combination of gears and tubes.
With the advancement of technology and machines now we can explain accurately the human mind working with practical experiments and research.
The human body is divided into two systems:
1. Central nervous system: Our central nervous system includes the brain and spinal cord.
2. Peripheral nervous system: PNS includes the rest of the body
What is inside the brain: After 15-20 days of gestation development of neuro-system started. Brain started from a tube shape to a jelly round shaped. Brain weight around 2 percent of the body’s weight and consumes around 20-25 percent of energy.
Suppose a human weighs 80 Kg and requires 100 units of energy per day His brain weighs around 1.6 kg and consumes around 20-25 energy units. Many of us fascinated by what is inside the human skull and what it contains?
Before we go in-depth we should understand these important cells and their work.
Neurons: Human body is a combination of cells that performed specialized tasks. Like other cells, the neuron is a specialized cell that transmits messages to another neuron. It is like wires in an electrical system that carry current from one place to another. It has three parts which generally found in many neurons.
(1) Dendrites: Input – Receive messages
(2) Axon: Transmit messages
(3) Terminal buttons: Output –send messages to another
There is a slight gap between the terminal button of a sending neuron and the dendrites of receiving neuron. This gap is called the synapse.
Inside our brain, there are millions of different neurons and trillions of connections between them. A single neuron may have thousands of connections with others neurons.
How neuron communication:Information that comes from a neuron that moves along the axon and transmits it to another via terminal buttons. This process is called neural impulse or action potential.
The action potential is an electrochemical impulse that travels through neurons. This action potential initiates from ions which are electrically charged particles. When the body is at rest no action potential is there.
Suppose we are at rest no action potential but when a nail or any sharp object strikes to foot, the pain receptor located in the foot send messages to the brain via neurons. Activation of neuron send electro-chemical to brain and brain send command to foot ‘remove foot from there.
What is the speed of action potential:
The speed of action potential can vary and depend on whether the neuron is myelinated or not. Usually, action potential sped vary from 01 to 120 meters per second.
Features of Neurons :
1. Neurons follow all or none principles. Neurons can do only one function that is firing and send signals to other neurons. In response to any input whether neuron fires and send signal or not fires.
2. A neuron can send 1000 action potentials per second. Action potential follows a wave pattern, one follows another action potential. This we can observe when we are in extreme pain.
The frequency of pain and sensation can be felt. In light sound neuron fires an action potential generated at a lower frequency but when sound becomes louder frequency of action potential increases with intensity. The neuron sends one signal at a uniform strength and speed. The number of pulses can differ depending upon intensity.
3. Each neuron does not completely connect with another. There is a slight gap between neurons called synapses. The chemical neurotransmitter is released at synapses and they bind to a receptor of another neuron.
4. When neurons do not get adequate oxygen and nutrition they start to die. Once a neuron dies they never born again. In an Ischemic stroke where oxygen supply interrupted a person’s faint and start losing consciousness. Deprived oxygen neurons start to die under 05 minutes of deprivation.
5. A neuron has its own electrical value, it can be positive or negative.
6. Collection of neurons called nerve cells.
7. The size of a neuron is approximately 100 microns.
Conclusion:
Neurons is the basic unit of the brain which receive input passes to other neuron, muscles or gland. Sensory neurons transmit signals from receptors (eye, ear, etc) to the central nervous system). Motor neurons carry output signals or commands from the central neuron system to glands, muscles. Interneuron connects both sensory and motor neurons.