The cerebrum is the largest part of the brain. It occupies the upper part of the skull and consists of two oval hemispheres. Each area of this complex nervous system performs a specific and equally complex function.
What is the cerebrum?
The cerebrum is also called the end brain, or cerebrum in Latin. This is the largest and evolutionarily the newest part of the human brain. It occupies the upper portion of the cranial cavity. With the exception of the medulla (Latin for “extended medulla”), the pons(Latin for “bridge”) and the cerebellum, it consists of virtually all parts within the skull. The two hemispheres are split longitudinally down the middle and connected below by the corpus callosum, the brain bar. These two hemispheres communicate with the brainstem. The surface of the cerebrum is called the cerebral cortex and is littered with many cerebral convolutions, or furrows. When these strong convolutions are spread out, the surface area increases immensely. The skull consists of several bones grown together. Below these bony parts, brain lobes are formed, which are named after the bones above. Motor and sensory functions, as well as mental activities, are controlled in the end brain. Mental activities include things like perception, imagination, judgment, reasoning, and decision making. With each function and activity, a variety of electrical waves are generated. As an electroencephalogram, these can be recorded to help locate disorders, or to determine brain death.
Anatomy and structure
The cerebrum belongs to the central nervous system and is the largest component in it. It consists of right and left hemispheres of the brain, the hemispheres. These are connected below by the corpus callosum so that they can communicate with each other. The corpus callosum, which belongs to the white matter, consists of a thick bundle of nerve fibers. Each of these hemispheres is subdivided into four other lobes of the brain: the frontal, temporal, occipital, and parietal lobes. The frontal and parietal lobes are separated by the central furrow. This also demarcates the anterior motor cortex from the posterior somatosensory cortex. Below, the frontal and parietal lobes are separated from the lateral temporal lobes by the sylvian groove. Similarly, the parietal lobes are distinguished from the occipital lobes by means of a furrow. The cerebrum consists of both an outer gray cortex and an inner white medulla. The outer cortex is a folded substance and resembles a walnut. It consists of many neurons whose nerve fibers project into the cerebral medulla. These nerve fibers are coated with myelin and give the characteristic white coloration.
Function and tasks
The cerebrum consists of four lobes that perform different tasks. They control a person’s thoughts, senses, and movements. The corpus callosum conducts messages between the two halves of the brain. The right half of the brain controls the left side of the body and the left half controls the right side of the body. The frontal lobe, as the name implies, is located in the forehead area. It has a prefrontal and motor cortex. This is where activities such as emotions, creativity, planning, judgment, movement and problem solving are controlled. The prefrontal cortex is responsible for higher mental tasks and thus reflects a person’s personality and culture. Voluntary movements are controlled in the primary motor cortex. A particularly large area is occupied by the movements of facial expressions and those of the hands. Behind the frontal lobe on the upper side of the brain is the parietal lobe. This area directs the senses of taste, pressure, temperature, touch, and pain. The temporal lobe is found on the right as well as left side behind the temples. This part plays a major role in most auditory and speech functions. Likewise for emotions and learning processes. The occipital lobe is located on the posterior inferior side of the end brain. This lobe controls vision and has the ability to recognize objects. The retina of the eye sends signals to this part of the brain, which are then processed into images.
Diseases and disorders
Because all four lobes of the brain perform different functions and tasks, symptoms also vary when these areas are damaged.The frontal lobes are responsible for a person’s emotions and personality. If a part of this brain area is destroyed by an accident, or tumor, the character of a person can also change. In some cases, pseudo-depressive disorders occur. The affected person shows little emotion, is listless, and has a decreased desire for social contact and sexual interaction. In other cases, the patient is pseudo-psychopathic. Social and sexual desire is more unrestrained and increased. Motor movements uncontrolled. Other disorders of the cerebrum may affect the vascular system. After a stroke, the gray cells of a crucial part are insufficiently supplied with oxygen. A lack of oxygen leads to the death of these cells. Depending on the severity and duration of the circulatory disturbance, this area of the brain may be unable to function permanently, or for a short time. This can lead to paralysis of the extremities on the opposite side of the body, or to speech and vision problems. A drooping corner of the mouth, or a tongue hanging out are also very characteristic of this condition. Increased pressure inside the skull due to increased cerebrospinal fluid can lead to problems walking and dementia. This is the case with hydrocephalus. Infections such as meningitis, encephalitis, or a brain abscess are also known and can cause serious symptoms. So are epilepsy, tumors, autoimmune diseases, and degenerative changes such as Alzheimer’s disease.
