The Cerebellum which is located at the base of the brain, receives information from the sensory systems, the spinal cord, and other parts of the brain and also regulates motor movements. It is only 10% of the brain. This part of the brain is also found in primates that came along before humans. Scientists are sure this is the oldest part of the brain.
The Temporal lobe which is located just above and forward from the Cerebellum. This lobe is involved in processing sensory input from the eyes to a small extent, it processes our language, and our emotions.
The Occipital lobe is the major visual processing center of the brain.
The Frontal lobe does the planning, organizing, and problem solving. This part of the brain also runs the higher cognitive functions including behavior and emotions.
The Parietal lobe regulates all of the sensory information that comes into the brain.
The reason we know what each part of the brain does, is because neurosurgeons (doctors that operate on the brain) have been able to probe different parts of the brain and while the patient is conscience and they can tell the doctor what is happening.
Scientists believe, because of the much smaller skulls found in the beginning of the evolution of humans, that in the beginning we were very primitive. And as time went on and we progressed, we added more advanced parts, until it is what we carry around today.
As a side note, I believe, that, one day, we may evolve a part of the brain that will allow us to communicate with other humans by way of telepathy thoughts which will be sent from one person to another without talking one work. Who knows, we may evolve to not needing our larynx and lose it because we no longer have the need to talk to one another. I hope not.
What is more fascinating, is the fact that some salamanders living in caves where there is no light, have actually lost their eyes. We see the socket, the primitive eyeball, but the eye has turned itself off, because it has no use in the total blackness of a cave. That’s evolution for you.