How does our brain work? How many neurons are there and what are the functions of the neocortex? Modern scientists scrupulously explore the features of our brain and discover more and more interesting details.
Thanks to the development of higher nervous centers, a person defines himself and his place in society, consciously controls his behavior and is able to adapt to a new environment. All of these benefits are associated with the functions of the cerebral hemispheres, which we will consider.
Human brain features
The human brain weighs approximately 1 kg 200 grams - these are average figures. It consists of 5 main parts: it is the final, intermediate, middle, hind and medulla oblongata.
Large furrows (depressions) share 4 main parts of the cerebral hemispheres: the frontal lobe of the parietal; and the parietal - from the occipital; the temporal lobe adjoins three others. The last, fifth lobe is islet, which is located in the depth of the lateral fossa. The harmonious interaction of all neurons ensures the growth and development of our personality, our character and abilities.
We can distinguish a separate function of the cerebral hemispheres - the ongoing development. The human brain is constantly developing. Everything that an individual reads, sees, perceives, he literally absorbs into himself. Especially important is the new information for children under 2 years old, at which time their neurons are actively building connections for the future.
The cerebral hemispheres. Structure and function
There are 14 to 17 billion neurons in the cortex; and there are many times more connections between cells. Neurons are connected by synapses. And various neurotransmitters - chemicals that activate the nearby synapse - help to activate the connections.
The hemispheres of the brain have a special structure. Thanks to folds consisting of furrows and convolutions, the area of the cortex increases significantly. According to some reports, the total area of the cortex of an average person is 2200 square meters. cm.
Under the cortex is the subcortex, or white matter of the brain. The hemispheres are interconnected by the corpus callosum. And even deeper are the ventricles of the brain - spaces filled with cerebrospinal fluid.
The cortex consists of layers of nerve nerve cells that alternate with layers of their branches - axons. There are 6 layers in total:
- molecular layer;
- external granular;
- external pyramidal - contains mainly pyramidal neurons;
- internal granular;
- internal pyramidal;
- layer of fusiform neurons.
Fusiform neurons gradually pass into the white matter of the brain. Conscious actions take place in the cortex, speech is formed. In the lower deep parts under the cortex are centers of unconscious reflexes and control of internal organs and organ systems.
Brain areas
To understand the functions of the cerebral hemispheres, you must first disassemble their structure. The hemispheres are conditionally divided into several centers in which certain psychological and physiological processes take place. These centers are not separate entities. All neurons of all networks constantly interact with each other. This is confirmed by many researchers.
But nevertheless, it is possible to distinguish some areas in the gray matter of the brain, which are more specialized in individual tasks.
Neurophysiologists distinguish the following areas of the brain:
- Occipital area.
- Temporal - is responsible for the sense of smell and taste. These two feelings are highly interconnected.
- Visual area. Here the signals coming from the eyes are deciphered.
- The parietal is the so-called zone of musculocutaneous sensitivity.
- The frontal lobe is the conscious behavior of a person, his attitude and labor activity. The back of the frontal lobe is the motor center.
The functions of the cerebral hemispheres, as we see, are distributed in zones. Some areas have several functions. For example, the hands are connected in the cerebral hemispheres with two zones - motor and sensory.
And if during a traumatic brain injury any of the indicated areas is damaged, then the function of this zone will suffer or completely disappear. You can restore lost function if another part of the brain - the one where the neurons associated with damaged tissues were located, can take on all the work of the lost center.
Bark function
So what are the functions of the cerebral cortex? The cerebral cortex is responsible for conditioned reflexes formed during the accumulation of experience. Also in the cortex pass all the higher mental processes. Here are concentrated areas of memory, speech, thinking. This is a later biological structure compared to the ancient central brain, and it is poorly understood. But it is known that our personality and character traits, the ability to assimilate and analyze information are embedded in the cortex.
Associative areas play a large role in shaping skills and habits. We can say by exaggerating the information that the most basic function of the cortex of the cerebral cortex is precisely associative. Indeed, on the basis of these mechanisms, a personality is also formed.
Associative areas 3:
- parieto-occipital-temporal;
- prefrontal associative;
- limbic.
The joint work of these centers provides a comprehensive analysis of information coming from outside. Without these higher centers, man would not be able to purposefully carry out work.
Physical activity
The most important function of the cerebral hemispheres is physical activity. In the front sections of the precentral gyrus there is a center where the projection areas of the feet and lower legs are localized. In the middle part of this gyrus there are cells working with signals of the upper extremities, and the deepest part of the precentral gyrus is responsible for the work of the muscles of the face.
The coordinated work of the receptors of the conduction nerve pathways and these brain centers provides us with walking, working with our hands, and other motor activity. And all this is controlled automatically. After all, the athlete does not think how to bend his leg while running. It is enough to give a start signal consciously.
Memory and speech
In the formation of memory, the medial temporal zone and the hippocampus play a role. However, they are not the place where the accumulated information is stored. These are more likely service areas. It is believed that a person remembers everything that he saw or heard once. The main problem is the ability to reproduce information and transcode it into words.
The area of speech is the border of the temporal and parietal zones. Moreover, a person distinguishes 2 zones: the center of Wernicke, which is responsible for speech perception, and the center of Brock, which is responsible for pronunciation.
What is the best way to remember information?
One of the functions of the cerebral hemispheres, as we now understand, is the memorization and reproduction of encoded information in words. If you keep in mind and constantly repeat the same words, then the information will remain only in the speech zone and after a few days will disappear.
To memorize information more deeply, it is necessary to apply imaginative thinking, associating each abstract concept with bright objects.
In the deep memory, we retain only those aspects of reality that are associated with vivid impressions and strong lasting emotions. And our emotions are “based” deep in the white matter - in the amygdala. The functions of the cerebral hemispheres are associated with purely conscious intentions to remember.
Stress and depression impair the brain's ability to remember something. To start learning material in a restless or irritable state is simply useless.
Conclusion
What about the functions of the cerebral hemispheres? All centers of the brain are closely interconnected. Speaking about specific areas, scientists mean the accumulation of neurons, which are more than other interconnected networks involved in a particular mental process.
The formation of memory, the ability to speak and think in words is the most complex mental process. This takes a large amount of energy, and a lot of nerve cells are involved in the speech.
The cerebral cortex is directly related to conscious processes, and the subcortex is associated with the unconscious, deep parts of the personality that Freud called It.