Frontal Lobe: Structure, Function & Diseases

The frontal lobe is the name given to an area in the cerebrum that is partly responsible for controlling movements, emotions, and personality. Its structure is as complex as the number of diseases and conditions it can cause.

What is the frontal lobe?

The frontal lobe, also called the frontal lobe or lobus frontalis, is one of four subareas of the neocortex. It is located in the frontal area of the cerebrum and performs important tasks such as controlling motor functions and emotions. Moreover, it is considered the seat of personality and self-awareness. Because of these characteristics, it is also called the “organ of civilization” by some scientists and authors. Its multiple functions mean that diseases or disorders of the frontal lobe quickly affect the psyche of the affected person. Tumors and dementia, both diseases that frequently occur in connection with the frontal lobe, entail changes in the personality structure. Especially the humor center is affected and changes drastically in the course of mentioned diseases.

Anatomy and structure

The frontal lobe is located in the anterior cranial group. Beginning at the anterior pole of the brain, it extends to the sulcus centralis, a furrow that serves as a separation between the frontal and parietal lobes. Beneath the frontal lobe is the insular cortex. The frontal lobe can be divided into three areas: The motor area, the premotor area, and the prefrontal area. The latter is called the prefrontal cortex, while the first two areas together are also called the motor cortex. The frontal lobe houses different convolutions, which are responsible for different tasks. For example, the praecentral gyrus, the inferior frontal gyri, and the orbital gyri. Blood supply to the frontal lobe is via the anterior and middle cerebral arteries. While the anterior cerebral artery is responsible for blood supply to the medial part of the frontal lobe, the middle cerebral artery supplies the lateral part. Blood drainage occurs via the ascending superficial veins of the brain, with the middle superficial cerebral vein also draining blood from the frontal lobe. From here, blood flows via the superior sagittal sinus and from there into the transverse sinus. From the middle vein, it continues via the cavernous or transverse sinus and from there into the internal jugular vein, which leads out of the skull.

Function and Tasks

The frontal lobe has a variety of different tasks. Primarily, it is responsible for movements. A distinction is made here between primary motor cortex, which is responsible for the execution of movement, and premotor cortex, which is responsible for the selection of necessary movements. The supplementary motor cortex synchronizes both areas and thus enables actions appropriate to the situation. In addition to these functions, the frontal region is responsible for cognitive tasks such as the control of emotions, personality and humor. This can be observed, for example, in individuals with damaged frontal lobes. These deviate significantly from the norm in terms of humor and lose the ability to understand more complex forms of humor. An important part of the frontal lobe is also the so-called area 24. In this area of the brain there are particularly many pyramidal spindle cells, which are only present in humans. This suggests that these cells and the area in which they are located are responsible for important aspects such as language development and the development of self-awareness. In general, it is thought that Area 24 in the frontal lobe may have played an important role in human evolution.

Diseases

Various diseases and disorders can occur in the frontal lobe. The best known is probably Pick’s disease, which is also known as frontotemporal dementia and occurs in the frontal or temporal lobe of the brain. In the course of the neurodegenerative disease, which usually occurs before the age of 60, there are initially changes in personality. Affected individuals alternately suffer from symptoms such as apathy, listlessness, and affective flattening and impulsivity, as well as euphoria. Moreover, there is a loss of ethical values and general disinhibition phenomena.In the further course of the disease, muscle stiffening occurs and subsequently the need for care. Another complaint, which mainly originates in the frontal lobe, is the so-called astrocytoma. This is a brain tumor that occurs in middle age and arises in the central nervous system. It is initially associated with epileptic seizures and later with personality changes. This is due to increasing intracranial pressure, which can also cause headaches and lethargy. The disease is not necessarily fatal, but affected individuals usually do not live to a ripe old age. Glioblastoma is also a brain tumor. In detail, it is a malignant tumor, which is accompanied by typical symptoms such as headaches, personality changes and other disorders. The disease usually ends fatally for the affected person in the course of about five years. Epilepsy also originates in the frontal lobe. It is accompanied by seizures and other symptoms and can be treated well nowadays. Due to the large number of different epilepsy diseases, various examinations must be carried out before a comprehensive treatment of the patient is possible. In addition to these diseases and complaints, there are many other disorders that can occur in connection with the frontal lobe. What they have in common is that drive disorders, disturbances in memory performance and disturbances in attention can occur in the course of the disease. Creativity, word fluency, and spontaneous behavior are also reduced.