What it is
Like chemical elements that are connected by different types of connections, the left and right hemispheres of the telencephalon are connected to each other by the corpus callosum. This structure acts as a connecting bridge between two parts of the brain.
The corpus callosum is a structure consisting of clusters of nerve fibers - axons (up to 300 million), and is located under the cerebral cortex. This formation is unique to mammals. The body consists of three parts: the posterior section is the roller, the anterior section is the knee, which later turns into the key; The trunk is located between the roller and the knee.
Anatomy and functions
The corpus callosum is covered on top by a small layer of cerebral gray matter, which explains, accordingly, the gray covering on it. Upon visual examination, 3 main sections can be distinguished:
- trunk (or midbrain);
- knee (part of the brain located in the front);
- beak or splenium of the corpus callosum (posterior section).
The brightness of the large commissure (when viewed on photographs or in section) is provided by fibers that are located radially and are located in each of the hemispheres.
The middle section, when viewed, looks like a bulge, which is also the longest part of the entire brain. The posterior section is visually visible as a thickening relative to other sections and zones, which is freely located above neighboring areas of the brain. The gray matter is represented by stripes and is located on top.
Functions provided by the corpus callosum:
- transfer of information (impulses) important for the functioning of the body from one hemisphere to the other;
- formation of the main characteristics that define personality and its characteristics;
- basic (basic, defining) skills and the possibility of their application throughout a person’s life;
- work on the formation of the emotional and personal sphere.
History of discovery
Despite the active study of brain structures in the last century, the functions of the corpus callosum have long remained in the shadows of the scientific microscope of researchers. Fiber formation received close attention from the American neuropsychologist Roger Sperry, who later received the Nobel Prize for his study.
The scientist performed a series of surgical interventions on the corpus callosum: like any neuropsychologist, Sperry cut the contacts, removed the structure and observed the functioning of the brain after the operations. He noticed a pattern: when the neural network connecting both hemispheres was removed, a patient who had previously suffered from epilepsy got rid of his illness. The researcher concluded: the corpus callosum is actively involved in the epileptic process and the spread of pathological excitation throughout different parts of the brain. In 1981, Roger Sperry was awarded the most prestigious international prize in the field of physiology and medicine for the results of his work.
However, despite such studies, the full functional set of this structure is still not discovered, and many mysteries in the functioning of the brain are associated with its activity, including the development of the schizophrenic process.
Recovery period and life prognosis
The prognosis for life with benign glioma depends on the timeliness of treatment and the degree of malignancy of the tumor. The necessary information about the tumor can only be obtained through a comprehensive and thorough diagnosis.
Low-grade gliomas are attempted to be completely removed surgically. Usually this does not cause any difficulties due to the localized nature of the pathological focus. Surgical treatment is the gold standard of neurosurgery.
It is impossible to indicate the exact life expectancy after surgery for brain glioma. If the patient seeks help on time, and the neurosurgeon manages to completely remove the tumor, the prognosis for glioma will be favorable. Life expectancy can be increased with subsequent radiation therapy. It allows you to increase the five-year survival rate after surgery to 60%.
It is also important to follow all doctor’s recommendations during the rehabilitation period. During recovery after removal of a brain glioma, the patient is under the supervision of specialists of a narrow and broad profile. They monitor important indicators of the body’s functioning, help normalize overall well-being and restore impaired functions of the nervous system.
What is the corpus callosum responsible for?
Possessing a colossal number of axons (structures responsible for transmitting electrical impulses to nerve cells), the corpus callosum literally connects the two hemispheres of the brain. Its fibers connect similar areas of the cortex (for example: the parietal cortex of the left hemisphere connects to that of the right). Thus, the fibrous cluster is responsible for the coordination and joint work of both parts of the brain. An exception is the temporal cortex, since the structure adjacent to the corpus callosum, the anterior commissure, is responsible for its connection.
The corpus callosum allows one hemisphere to “share” information with the other: when conducting experiments on higher mammals, it turned out that, by cutting the optic tract, the corpus callosum transmits information from the visual cortex of the left hemisphere to the right.
The functions of this structure also include maintaining human intellectual activity: by synthesizing information from two parts of the brain, the corpus callosum provides a deeper understanding of data received from outside. An experiment supports this position (all neurophysiology is based on experimental data): by dissecting and extracting a cluster of connecting nerve fibers, scientists noticed that the subjects were finding it difficult to understand written and spoken speech.
The most interesting and mysterious functions include the unity of consciousness and emotional response to a stimulus. When the corpus callosum was removed, people tended to show an ambivalent attitude towards the phenomenon or object (ambivalence). That is, they observed the presence of two diametrically opposed thoughts or emotions at the same time, such as: hatred and love, fear and pleasure, disgust and interest. A similar phenomenon is observed in the psychopathology of schizophrenia, when patients, without realizing it, showed love and hateful enmity towards something. This is not about the alternate manifestation of opposite feelings: emotions are located on parallel lines and in the same period of time.
Corpus callosum in men and women
Male and female brains develop differently: from the prenatal formation of the neural tube according to sexual characteristics and ending with the lifelong action of hormones. Recently, you can often hear that the female body is no different from the male body. However, this is not true: neurophysiology, psychophysiology and neuropsychology provide a lot of experimental data in favor of the differences between the male and female brains.
This also applies to the corpus callosum, namely: the number of nerve fibers corresponding to the structure is greater in women than in men. This study suggests that the female sex operates better with speech concepts. Possessing a larger apparatus for exchanging information, a woman thus balances between the hemispheres, when the male brain “specializes” in one of them. However, in contrast to this statement, there are many reproaches.
Malignant and benign gliomas
Neoplasms can be benign or malignant. The exact type of tumor is determined by a neurologist or neurosurgeon based on the diagnostic data.
Experts distinguish three main types:
- astrocytomas;
- ependymocytes;
- oligodendrogliocytes.
Depending on the degree of malignancy, tumors come in several types. Juvenile and giant cell astrocytomas are considered benign. They are classified as the first degree and are considered the most harmless. Glioma of the second stage is borderline. It is growing slowly and has a favorable prognosis. But without timely treatment, it easily transforms into a tumor of the third and fourth degrees of malignancy.
Diseases
Dysgenesis , also known as dysplasia of the corpus callosum of the brain, is a congenital pathology of the nervous structure, manifested in its abnormal development of individual areas and tissues. The disease is the result of a defect in certain chromosomes. The disease is accompanied by a violation of the tissue composition of the corpus callosum and entails a violation of its functions.
The consequences of dysgenesis of the corpus callosum of the brain manifest themselves in the form of disorders of the neurological and mental sphere of a person. These include:
- slower response to external stimuli;
- slowdown in the development of intellectual properties of the psyche;
- impairment of recognition and understanding of written speech;
- dyslexia;
- difficulty and inhibition in the processing of light signals by the brain.
In addition, there is also another pathology - the absence of the corpus callosum of the brain in a newborn - agenesis.
Agenesis
This pathology spreads to an average of 3% of the population, which is a fairly high figure. Agenesis of the corpus callosum is a disease that is often accompanied by other ailments. The congenital absence of a hemisphere-connecting structure has its own symptoms:
- Slowing down of the child’s psychological and neurological development;
- facial dysmorphism - impaired blood flow to the facial muscles;
- pathology of the gastrointestinal tract, kidneys and the presence of tumors;
- excessively rapid sexual development;
- epileptic seizures;
- gross violations of the development of internal organs;
- defects in the development of the visual system;
- diseases of the musculoskeletal system;H
Hypoplasia
This pathology is characterized by incomplete development of the tissues of the corpus callosum. Unlike the previous disease, hypoplasia is manifested by underdevelopment, and not a complete absence of structure. Hypoplasia of the corpus callosum of the brain in a child is diagnosed by doctors during the first months of life, because the manifestations of the disease are distinctive:
- spasms of unobvious origin;
- epileptic conditions (fits, local convulsions);
- faint cry of a baby;
- absence or impairment of the sensitive sphere, that is, the child may not hear, see or smell;
- weakening or lack of muscle strength, resulting in atrophy or very weak muscles.
The consequences of hypoplasia of the corpus callosum of the brain are unfavorable, and in the absence of proper diagnosis, the prognosis is unfavorable. In 70% of children with this pathology, they suffer from severe mental retardation.
In dry but important remainder
Thus, the corpus callosum of the brain, despite its tiny size, has a great influence on a person’s life.
It allows the formation of personality, is responsible for the emergence of habits, conscious actions, the ability to communicate and distinguish between objects. That is why it is extremely important to take care of your health during pregnancy, since the main metabolic disorders are formed during this period.
We should not forget that the corpus callosum forms the intellect and makes a person a personality. Despite all attempts to study this structure, scientists have not yet been able to uncover all its secrets, and therefore very few methods for treating disorders, if any, have been developed.
The main ones are drug therapy and a special set of exercises - exercise therapy, which allows you to maintain optimal indicators of physical development. Measures to eliminate the symptoms of disorders should be taken immediately, otherwise the desired improvements may not occur.