It is in this region, known as the cerebral cortex, where most of the processing of the cerebrum takes place. The surface of the cerebrum, with its many convoluted gyri and sulci, is extremely important to the function of the brain. Often referred to as the 5th lobe of the brain, the insula is made of deep cortical material that is covered by regions of the temporal, parietal, and frontal lobes. The lateral sulcus widens at the bottom like an upside down letter T to form a region of cerebrum known as the insula. Posterior to the temporal and parietal lobes is the occipital lobe, which forms the most posterior region of the cerebrum.The temporal lobe extends laterally and inferiorly from the parietal lobe and is separated from the frontal and parietal lobes by the lateral sulcus.Posterior to the central sulcus is the parietal lobe, which forms the center of the cerebrum.The frontal lobe is the most anterior region of the cerebrum that extends posteriorly to the central sulcus.At the inferior end of the longitudinal fissure is a band of white cerebral matter, the corpus callosum, which connects the two cerebral hemispheres.Įach cerebral hemisphere is further subdivided into four lobes that are named for the covering bones of the cranium. The longitudinal fissure divides the cerebrum along the body’s midline into two nearly identical structures, the left and right cerebral hemispheres. Several of the sulci and fissures act as important anatomical landmarks to mark the borders of larger regions of the cerebrum.
Most of the grooves are shallow depressions called sulci (singular: sulcus) while some are deeper depressions called fissures.