The basis of higher nervous activity is conditioned reflexes that occur during the life of the body and allow it to expediently respond to external stimuli and thereby adapt to constantly changing environmental conditions. The conditioned reflexes developed earlier can attenuate and disappear due to inhibition when the medium changes.
Irritants for the formation of conditioned reflexes in humans are not only environmental factors (heat, cold, light, smell), but also words denoting a particular object or phenomenon. The exceptional ability of a person (unlike animals) to perceive the meaning of a word, the properties of objects, phenomena, human experiences, to think in a generalized way, to communicate with each other through speech. Outside of society, a person cannot learn to speak, perceive written and spoken language, study the experience gained over the long years of the existence of mankind, and pass it on to descendants.
A feature of human higher nervous activity is the high development of rational activity and its manifestation in the form of thinking. The level of rational activity directly depends on the level of development of the nervous system. Man has the most developed nervous system. A feature of the higher nervous activity of a person is the awareness of many of the internal processes of his life. Consciousness is a function of the human brain.
The higher nervous activity of a person is significantly different from the higher nervous activity of animals. In a person in the process of his social and labor activity, a fundamentally new signal system arises and reaches a high level of development.
The first signaling system of reality is the system of our immediate sensations, perceptions, impressions of specific objects and phenomena of the surrounding world. A word (speech) is the second signaling system (signal of signals). It arose and developed on the basis of the first signaling system and matters only in close interconnection with it.
Thanks to the second signaling system (word), a person more quickly than animals forms temporary connections, because the word carries the socially developed meaning of the object. Temporary neural connections of a person are more stable and persist without reinforcement for many years.
The second signal system has two functions – communicative (it provides communication between people) and the function of reflecting objective laws. The word not only gives a name to the subject, but also contains a generalization.
The second signal system includes the word audible, visible (written) and spoken.
The first signaling system is understood to mean the work of the brain, which determines the conversion of direct stimuli into signals of various types of body activity. The second signaling system denotes the function of the human brain, which deals with verbal symbols.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.