The brain top is surrounded by cerebrospinal fluid that cushions the skull and spinal cord. It is protected by a tough outer layer called the dura mater and a thin inner sheath of web-like connective tissue called the arachnoid mater. Long nerve fibers (axons) run beneath the cortex connecting different areas of the brain to each other and to the body. These pathways are called white matter tracts.

The cerebrum is the top part of the brain, made up of two hemispheres separated by a deep groove that’s called the corpus callosum (corp-uh-call-um). It receives and gives meaning to information from our sense organs and controls the body’s movement.

Exploring Brain Top: A Guide

There are four lobes in the cerebrum, frontal, temporal, parietal, and occipital. Each lobe has very specific functions and they work together. The frontal lobe handles things like attention, behavior control and the ability to speak. It also processes emotions and consciousness. Other mammals besides humans don’t have the same amount of development in their frontal lobes.

The thalamus is a bridge between the brainstem and cerebral cortex. It sorts sensory information from your eyes, ears, nose and mouth (except smell which bypasses the thalamus). It relays these signals to the primary visual, auditory, and tactile cortical areas. Neighboring points in the primary visual cortex correspond to nearby body parts, creating a map of your body known as a retinotopic map. The parietal lobe processes the sense of touch – pressure, heat, cold and pain – as well as proprioception, which is the sense of where body parts are located in space.