الفهرس 
بنية الدماغ البشرييوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Nerve cells form the nervous tissue, the most important living tissue at all, in which the feeling of existence is concentrated, and on it our bodies depend on all its sensations, so there is no internal and external stimulus except that each neuron responds to it in their own way, and then translates what it was affected by in the form of electrical impulses, which are transmitted to the cell It takes no more than one millionth of a second, and reaches the brain through millions of neurons in a time not exceeding ten seconds.
The ”brain” is responsible for most of the human operations, starting with his ability to read, write, learn, collect and remember, all the way to issuing orders to the muscles and nerves to carry out their functions. The centers of the senses are found in it: vision, smell, taste, and so on. Also, all the movements that we make are considered one of the responsibilities of the brain and the nerve cells it contains. One of the most important functions of the central nervous system is the transfer of information, i.e. securing the necessary communications between its various parts, on the one hand, and between it and the outside world, on the other hand, and information is transmitted within the brain by signals of an electrical and chemical nature. As for the signals that appear within the nerve cell (neuron), they are often electrical signals, while the signals exchanged between the different nerve cells (neurons) are of a chemical nature. Neuroscience’s greatest challenge has always been to make the intellectual leap between a flake of brain tissue and thought and emotion--even a dream, in both the professionals of the word: the literal phenomenon of that strange inner world that unfolds during sleep, as well as the metaphor used to chart the wonderful outcomes of our lives. It’s a journey we’ll need to take in three steps: first, get to know how the brain itself works; second, discovering how it changes throughout life; And third, looking at how these changes in the brain might amount to ’mind’. However, it is not even clear where to start. It is quite unlikely that consciousness is just a secondary phenomenon. Consciousness to some extent enhances the survival of its bearer, which means that the activity of the neuronal correlates of consciousness affects other neurons in some way, and this activity affects the correlates of the neurons of consciousness on other neurons that It eventually causes a behavior, and this activity can also retroactively supply the neuronal correlates of consciousness and of previous stages in the hierarchy with highly complex materials. Consciousness is the ability to suppress all aspects of the activity of the cortex and the inputs of the senses (preventing them from entering the realm of feeling) except for those related to a specific aspect, and this aspect is what we can call a chain or train of ideas. Consciousness is a searchlight that illuminates that location in the cortex or some of the senses’ imports, with an important activity of value for survival, and in general consciousness illuminates a particular idea or group of sensations, one at a time. This does not mean that the unconscious processes are not insignificant, but the processing of information associated with consciousness seems to be a sequential process, so that only one activity is followed at a time. However, it sometimes happens that the unconscious processes or signals are so strong that they pass the access control switch and rush into consciousness. There is no evidence of a center of self-awareness. What is likely is that this activity is closely related to the interconnected nature of the connections between the reticular system and the cortex. Only when this whole structure has reached a sufficient degree of complexity can consciousness arise. Interpreting it according to that vision is completely natural, as the level of consciousness increases with the increase in the complexity of the nervous system, and only in the most complex creatures - humans and chimpanzees - the cortex can carry two ideas almost simultaneously, the given idea and the idea of that idea. Identity theory held that minds are physical entities and that mental states are nothing but nervous states, and the theory based this on the fact that the physical world itself acknowledges this physical formation, and the theory unifies mental and cerebral processes, but this view seems correct only That it was accepted in the functionalist doctrine in a different way. The functionalist doctrine is convinced of the premises of the physical doctrine, but it itself is not a physical doctrine. The distinction is determined between the structure of the case and the course of the case. The first represents the descriptive nature of the case and the second means the occurrence of the case itself or its occurrence. It is an immaterial nature that is achieved through a physical medium, and therefore mental states are realized in procedural events and processes. Consciousness in the waking state, as opposed to the state of sleep or coma, is so closely related to the functioning of brainstem structures that the separate contributions of the brainstem and cortical systems were difficult to outweigh because these two machines functioned in combination; The reticular activator activates the cortex, which would otherwise remain dormant. Descartes asserted that the subject of consciousness is the mind, and that the mind is the thing or entity separate and different from the body. The mind, on the other hand, is completely different in nature. It takes up no space at all and has no shape, size or location. Its essence is simply that it has consciousness, i.e. thoughts, feelings, memories, perceptions, desires, and so on. Doctors believe that there is no pure mind, and the human mind cannot be understood apart from the conditions for the emergence of a living being. Thus, the mind can only be understood within a biological framework. They also see that life and the mind are the results of reflected actions and preparations or abilities in the living body that are recorded by neurons and arranged and regulated by the nervous system, but with the further development of living organisms and the complexity of their structure and functions, the mind goes beyond that biological framework. Life involves a continuous novelty, for from a small number of chemical elements, various developed cells emerge, which are living organisms. Likewise, from a number of vital functions linked to the nervous system, different images emerge from the mind about the phenomenon of life. Thus, the biological dimension does not conflict with the emergence of the mind. The question is what is the relationship between consciousness and the brain? It is the famous mind-body problem, and its solution is simple, which is that states of consciousness are caused by neurobiological processes from a lower level within the brain, and conscious states are in themselves higher-level features of this brain. onsciousness we know for a fact that this happens in the brains of humans and there is evidence that this also happens in the brains of many species of animals.” It is said that the human brain is the most complex thing in the world we know; Compared to body weight, the human brain is much larger than all the brains of other organisms; It is three times larger than you might expect if you compare it to the brain of our closest relatives, the great apes. The human brain weighs about one and a half kilograms, and it consists of more than a billion neurons and billions of neural connections, and from these connections our exceptional capabilities appear; Such as perception, learning, memory, thinking, language, consciousness - in some way.