Properties of Nervous Processes
The classical typology by I.P. Pavlov relies on evaluating the fundamental characteristics of excitation and inhibition. Three key parameters determine individual behavioral features:
- Strength. Determines the working capacity limit of nerve cells. Exceeding this limit triggers protective transmarginal (peassimal) inhibition. Based on this criterion, the nervous system is divided into strong and weak.
- Balance. Characterizes the equilibrium between excitation and inhibition processes, as well as the nervous system's ability to adequately switch between them without tipping the scale to either side.
- Mobility. Reflects the speed at which nervous processes alternate in response to environmental changes. The opposite property to mobility is inertia.
Classification of HNA Types in Animals (Temperaments)
I.P. Pavlov established a direct physiological link between the properties of nervous processes and the ancient classification of temperaments proposed by Hippocrates (which originally relied on the predominance of body humors). Using dogs as a model, the following types were identified:
- Sanguine: possesses a strong, balanced, and mobile nervous system.
- Choleric: features a strong, yet unbalanced organization with a pronounced predominance of excitation processes.
- Phlegmatic: characterized by strong and balanced processes that are nevertheless inert (low mobility).
- Melancholic: representative of the weak type. Due to rapid cellular exhaustion, other parameters (balance and mobility) cannot be clearly differentiated in these subjects.
Human HNA Specifics: Signaling Systems
Unlike animals, humans possess two signaling systems, creating an additional level of HNA typology.
The first signaling system is responsible for the direct perception of physical stimulus characteristics (light, sound, odors). It is common to both humans and animals. The second signaling system operates exclusively with words, which I.P. Pavlov called the "signal of signals." This forms the basis of human speech activity.
Depending on which system dominates, humans are divided into three specific categories:
- Artistic type: the first signaling system predominates. Individuals of this type tend toward emotional and imagistic perception of the world.
- Thinking type: the second signaling system dominates. Characterized by a pronounced inclination toward analysis and abstract thinking.
- Mixed type: both systems are in physiological equilibrium. This is the most common variant.
Systemic Organization of Behavior
Traditional neurology relies primarily on the reflex principle, classifying pathologies through the balance of excitation and inhibition. However, the theory of functional systems suggests evaluating brain lesions through the prism of goal-directed behavioral act stages.
Key stages of systemic organization include:
- Afferent synthesis.
- Decision-making.
- Formation of the action result acceptor (predictive apparatus).
- Efferent synthesis.
- Overt action.
- Achievement and evaluation of results.
Individual variations in the formation of these stages occur in every subject. Moreover, situational variability exists: the efficiency of links changes in the same individual depending on the context. Understanding this architecture opens new pathways in topical diagnostics and allows tailoring therapy to correct specific impaired stages rather than applying generalized brain stimulation.