How Does the Brain Work?
The human brain weighs just around three pounds and is estimated to be made up of 100 billion cells. It is considered to be the most important organ of our anatomy. It is responsible for telling our body parts what to do and when to do it.
The brain belongs to a network which the peripheral nerves and the spinal cord also belong to. Altogether, they control and transmit all the information sent or received from other parts of the body. If the body was a gadget or piece of equipment, the brain would be the main controller.
There are many different parts of the brain, and understanding how the brain works involves looking at what each of those parts do.
Parts of the Brain
The brain is divided into two hemispheres: the right brain, which is more oriented to visual learning, and the left brain which is the analytical side.
The human brain is composed of three major parts:
Each part has a special role to play in performing different tasks, ensuring the proper functioning of the brain and controlling the many functions of the body.
Brain Stem
The brain stem is connected to the spinal cord. Within the brain stem are the pons, medulla, thalamus, and midbrain. Each part has a designated task when it comes to the processing and sending out of information to the brain. The brain stem controls the body’s blood pressure, heart rate, basic reflexes, arm and leg movements, and digestion.
Cerebellum
Located behind the brain stem is the cerebellum. Its function is to process information related to arm and leg coordination and our sense of balance. About a third of the brain’s total mass is made up of the cerebellum. On top of the cerebellum and the brain stem are two cerebral hemispheres which are responsible for processes involving speech, thought, and memory.
Cerebrum
The cerebrum is the largest part of the brain upper and is the main part of the brain of vertebrate animals. It has left and right hemispheres. The cerebrum controls conscious and voluntary processess.
Neurons
A huge portion of the brain cells are actually neurons. They trigger the nerve impulses of the body. Neurons are not just limited to our brain but are also present in other parts of the body through the nervous system.
Neurons emit chemicals which are sent to other neurons through a synapse which refers to the gap or space between neurons. This triggers a specific activity. The chemicals which are sent from one neuron to another neuron to trigger activity are called neurotransmitters. Common neurotransmitters include norepinephrine and epinephrine.
Diencephalons
Sitting between the cerebral cortex and the brain stem is another segment of the brain, called the diencephalons, which combines the functions of the brain stem with the cerebral cortex.
Areas covered by the diencephalon are the hypothalamus and the thalamus which process our sensory information such as hunger and thirst, including our sexual and emotional responses.
Corpus Callosum
Dividing the two hemispheres is the corpus callosum, a white matter that forms a line between the hemispheres. Despite dividing them, the corpus callosum allows the two areas to communicate with each other.
The left portion of the cortex involves processes that are responsible for reasoning and language abilities while the right side functions for creativity and spatial perceptions.
Delivery of Information to the Brain
All information coming from the many parts of the body is delivered to the brain via the spinal chord.
As the information reaches the center of the brain, it spreads out into the other parts of the brain where it can be processed and is then sent out to other parts of the body to execute specific functions.
For example, as you touch a hot kettle with your hands, the information is sent to your brain and is transmitted back with high speed. As a reflex, you immediately let go because your brain is telling you that the object is hot and you feel the heat in your palms.
Most, if not all, information other than hearing and vision that is sent from your body parts all goes through the spinal chord and then to the brain. This explains why a person who is paralyzed as a result of some damage in the spinal chord can still have senses of sight and hearing.