Russian physiologist Ivan Petrovich Pavlov (1849-1936) he is best known for being the initiator of the classical conditioning paradigm, also called “Pavlovian”. However, Pavlov and his followers made other important contributions to psychology, such as his personality typology based on the study of the nervous system.
In this article we will describe the 4 types of personality that exist according to Pavlov’s theory, As well as the main concepts of this model, the most important of which concern the basic nervous processes (excitation and inhibition) and their properties, which determine the differences in behavior between humans.
Pavlov’s theory of personality
Pavlov developed his theory of personality through the experiments he conducted in his laboratory. More precisely, this author studied learning reflex responses in conditioning using dogs as experimental subjects; with regard to these animals, Pavlov’s studies on salivation are particularly well known.
Unlike other personality models in force at the time, including the psychoanalytic theory of Sigmund Freud, Pavlov not only focused on describing the psychological differences between individuals, but sought to explain them through “ the study of the activity of the nervous system, which gives rise to temperament, The basis of personality.
This is why Pavlov’s personality proposition is framed in biological theories, which use biologically related constructs to explain individual differences. The somatic typologies of Kretschmer and Sheldon, the phrenology of Gall or more common models such as those of Eysenck, Gray or Zuckerman belong to the same category.
Nervous processes and their properties
Pavlov’s personality typology is derived from his assumptions about the basic properties of the nervous system. In this regard, it is important to consider two physiological processes, arousal and inhibition, As well as its three main properties: strength, balance and mobility.
The excitatory and inhibitory nervous processes occur independently, although they interact giving rise to different states of cortical activity depending on the degree of predominance of each of them. The definition of these concepts is similar to the one we use today to talk about the sympathetic and parasympathetic nervous systems.
Pavlov said that differences in behavior between individuals are explained by properties process exciter and inhibitor of each person (or animal). He spoke of “strength” to refer to the overall working capacity of neurons, “the balance” between arousal and inhibition, and the “mobility” or speed of these processes.
Strength, balance and mobility would be the most relevant properties, but Pavlov also described the irradiation, or diffusion of the process to other areas of the nervous system, and its concentration in a given region. Later, his disciple Vladimir Nebylitsyn added a fourth property – the dynamism or speed of reflex training.
The 4 types of nervous system
According to Pavlov, the characteristics of the basic nervous processes in a given person determine the type of activity of his nervous system, and therefore his temperament. These biological traits would form the basis of the personality; by interacting with environmental factors, they would produce differences in behavior between individuals.
The criteria Pavlov used to make his ranking were quite arbitrary. He first divided the dogs into two groups depending on whether their nervous system was strong or weak. He then separated the forts according to whether they were balanced or not; finally, he created the categories “strong-balanced-slow” and “strong-balanced-impulsive”.
1. Strong and unbalanced
This type of temperament is characterized by the lack of balance between the processes of arousal and inhibition; there is therefore a tendency for the appearance of physiological states in which one of the two predominates in a very marked way.
One can relate the strong and unbalanced (or impetuous) personality to the angry temperament of the humorous typology of Galen, a Greek physician who lived in the 2nd century AD and from whom Pavlov was inspired. In the Eysenck PEN model, it would be comparable to high levels of extraversion and low levels of emotional stability.
2. Strong, balanced and slow
In this case, the neurons have a good working capacity and the balance between arousal and inhibition is adequate, but the rate of initiation and termination of these processes is low. The strong-balanced-slow type corresponds to introversion and emotional stability in Eysenck’s model, And with the phlegmatic type of Galen.
3. Strong, balanced and impulsive
Unlike the previous type, in the strongly balanced-impulsive type, the speed of the processes of excitation and inhibition is high. Following Galen’s classification, we would speak of blood temperamentAnd in Eysenck, these people would have a high degree of extraversion and emotional stability.
The fourth type is equivalent to Galen’s phlegmatic temperament and would exhibit introversion and emotional instability in Eysenck’s model. Pavlov defines it simply as a poor working capacity of nervous system cells.