Eysenck's theory

Eysenck combines the correlational tradition (descriptive or taxonomic model) with the experimental (causal or explanatory model). The descriptive model speaks of three independent dimensions to describe the personality: Psychoticism (P), Extraversion (E) and Neuroticism (N). The causal model links the dimensions with psychophysiological processes that explain the differences individual behavioral. For him. These differences are due to differences in the functioning of the NS.

Index

1. Background and influences of Eysenck's theory
2. The structure of the personality: descriptive or taxonomic model.
3. Extraversion in Eysenck's theory
4. Neuroticism (Emotional Stability-Instability)
5. Psychoticism and genetic bases
6. Eysenck Personality Questionnaires.
7. Assessment and conclusions

Typological approach:

• Galen the formulation of the theory of the four temperaments (melancholic, choleric, phlegmatic and sanguine) is attributed.
• Another contribution is due to Kant, who updated, popularized and made Galen's doctrine credible.

Wundt's contributions: He made the leap and went on to consider the separate categories (types) as continuous dimensions.

Psychiatric tradition:

• Gross he was the first to relate the extraversion dimension to a functional brain property.
• Heymans and Wiersma He was the first to realize the importance of quantifying the relationships between variables, proposing the use of correlational methods. He was also a pioneer in conducting experimental personality studies.
• Jung he popularized the terms Extraversion-Introversion.
• Kretschmer he attached great importance to the morphological constitution as an etiological element of mental illness.

Psychometric contributions:

• Spearman introduced FA in psychology, which made it possible to replace speculations with objective and quantitative data, and was the first to demonstrate the existence of strictly defined and measured factors (extraversion and emotionality or Neuroticism).
• He is also in debt to Guilford, since the first questionnaire developed by Eysenck to measure the dimensions of Extraversion and Neuroticism consisted of items that came from scales created by this author.

Experimental contributions:

• Pick up the influence of russian school that he develops a large number of experimental studies on individual differences of a psychophysiological type.
• Also the concepts of reactive and conditioned inhibition of Hull influenced Eysenck.
• The work of Duffy about arousal as non-specific energization of the CNS in response to stimulation, it also influences the theory of it remarkably.

Eysenck proposes a hierarchical personality model with different levels of increasing generality:

• First level: Specific Answers which can be observed once and which may or may not be characteristic of the individual.
• Second level: Common responses which would be specific responses that are repeated when the circumstances are similar.
• Third level: Traits which are theoretical constructs based on the intercorrelations between habitual responses that are observable. They would be factors of the first order, because they come out of the first AF.
• Fourth level: Types that arise from the intercorrelations between the different traits, and would be second order factors. They are considered continuous dimensions, along which the individual can be positioned, and not separate and pure categories.

The three types or superfactors (Extraversion, Neuroticism and Psychoticism) are sufficient to adequately describe the personality. The reasons for using types and not traits are:

• Different analyzes lead to the appearance of these three factors, and if more are obtained, they are usually not important.
• First-order factors are more unstable from one investigation to another.
• From these three types, satisfactory predictions can be made at different levels:

Physiological (individual differences in cortical activation, etc.), psychological (individual differences in performance, etc.) and social (differences in criminal behaviors, etc.).

Extraverted individuals are sociable, communicative, uninhibited, active, talkative, and dominant. They also seek excitement and stimulation. Eysenck has proposed two theories to explain the differentiated behavior of introverts and extraverts:

The excitation-inhibition model: Uses physiological processes without specifically locating them. He proposed that people who are predisposed to develop extraverted behavior patterns are those who have: weak excitatory potentials and strong reactive inhibition. People who develop introverted behavior patterns are those who possess: strong excitatory potentials and weak reactive inhibition. Therefore, physiological inhibition it is inversely proportional to behavioral inhibition.

The cortical activation theory: It appears because the previous proposal did not allow to make empirically testable predictions. According to this theory, people who have, under resting conditions, a chronically high level of arousalarousal, behave introverted. Thus, the greater the cortical activation, the less the behavioral activation, and vice versa. It proposes the SARA (Ascending Reticular Activation System) as the neurological basis responsible for the level of activation. chronically low tend to behave in an extraverted pattern. The ones that have

Some studies have shown that extraverts are oriented towards sources of stimulation in the environment that report a higher level of stimulation. These studies only show that extraverts prefer these situations, but not that they have a greater chronic cortical arousal. Proving this is not easy for several reasons:

• Due to the lack of a single and direct measure of arousal, since there is individual specificity of response (One person reacts to stimuli by increasing their heart rate and another by increasing their breathing).
• Because there is specificity of the response to the stimulus (different stimuli produce different activation patterns).
• The relationships between stimuli and responses are inverted U (Yerker-Dodson Law). Optimal performance would be obtained with medium levels of activation.

The results show that introverts present greater reactivity to sensory stimulation, and that introverts and extroverts do not differ in arousa under neutral or chronic conditions. Therefore, although the theory is not completely accurate, you are correct about the sensitivity of introverts to stimulation.

In performance studies, introverts perform better in situations with moderate levels of stimulation, and extraverts with high levels. Which indicates that they differ in the level of stimulation to perform better.

People with high scores on this dimension have frequent mood swings, are often worried, anxious, depressed, and feel guilty. They react strongly to stimuli.

The neurological bases are found in the limbic system or visceral brain, which is related to neurovegetative activation (sweating, heart rate, muscle tension, etc.). For Eysenck, the most unstable subjects show greater autonomic activation. This system and the SARA are only partially independent, since cortical arousal can occur through visceral activation.

The empirical evidence on this is unsatisfactory. There is no evidence that subjects high in neuroticism are more physiologically reactive. This inconsistency can be due to several reasons:

• 1. Automatic activation measures are not correlated with each other (increased heartbeat does not lead to increased electrodermal response).
• 2. There is the problem of individual response specificity.
• 3. Different stressors produce different patterns of physiological activation.
• 4. Inducing emotional states is unethical.
• 5. The dimension is heterogeneous, and since anxiety is not its only component, not all those who score high in this dimension have high anxiety.
• 6. People who score high are characterized by chronic worry, dissatisfaction, pessimism, and not by acute reactions.

People with high scores on that dimension are cold, self-centered, impulsive, and aggressive. They do not care about others and are indifferent to danger. Despite the many socially negative characteristics, Eysenck relates this dimension to the creativity and divergent thinking (as it inclines people to all kinds of weird or abnormal).

Impulsivity itself would also be one of its components, although some aspects of this characteristic (daring and seeking sensations) are included in Extraversion.

Eysenck has proposed that Psychoticism is related to an excess of dopamine and a decrease in serotonin. Dopamine reduces cognitive inhibition, and serotonin increases it. Several studies support this idea, since Psychoticism is linked to lower levels of serotonin. The relationship of dimension with creativity is also confirmed.

Although the theory proposes that the differences in the functioning of the different neurophysiological systems (responsible for the proposed dimensions) are of genetic origin, Eysenck does not believe that the behavior is in the genes. Genes do not cause behavior directly, but DNA affects a whole series of biological mechanisms intermediaries (physiological, hormonal and neurological) that in interaction with social factors produce the conduct.

He therefore proposes that the individual inherits certain physiological and neurological characteristics such as SARA, which influences the cortical arousal level, which determines the possibilities of conditioning, sensory thresholds and other processes basic. Thus introverts are better conditioned and have lower sensory thresholds. The different interaction of individuals with their environment produces the behavioral traits that characterize introverts and extraverts.

Many findings suggest that biological factors are important in the genesis of individual differences:

• Temporal stability or consistency: individuals tend to maintain their position in each dimension over long periods of time. It seems that daily events have little influence on dimensions.
• The dimensions have been found in cross-cultural studies, so biological factors must be important.
• Studies with mono and dizygotic twins reveal that genetic factors explain some of the variance of individual differences.

• MMQ: I was only evaluating Neuroticism.
• MPI: Evaluated Extraversion and Neuroticism.
• PPE: As the MPI that they weighed in both Neuroticism and Introversion and received criticism for the supposed dependence of both dimensions, refined the problematic elements in this inventory.
• EPQ: Evaluate the three superfactors.
• EPQ: Evaluate the three superfactors.

Dimensions of personality and well-being.

In recent years, many studies have been carried out on the association between Extraversion and Neuroticism with different measures related to positive and negative aspects.

Regarding affect, two dominant dimensions have been found, Positive Affect (PA) and Negative Affect (AN), and a lower level with specific emotional states. AN is a general dimension of subjective discomfort and dissatisfaction, and AP of satisfaction, joy, enthusiasm and interest.

Negative emotional states tend to run together, and the same goes for positive ones. AP and AN are not two opposite poles, but independent dimensions, and can be understood as states or as traits.

A positive relationship has been found between Extraversion and the AP trait, also between Neuroticism and AN. But Extraversion does not correlate with AN, nor Neuroticism with AP. It also seems that extraverts experience more positive events, have more positive feelings, and feel happier and more optimistic. Those who score high on Neuroticism have more negative feelings and consider themselves less happy.

If this is so, the effects of Extraversion and Neuroticism should also appear in the cognitive processing of affective stimuli. This is consistent with Bower's theory that emotions impose an organizational structure of information on memory. This could also apply to stable personality traits. Thus, individuals would develop associative networks due to their predisposition to those emotions. Consistent with this, Extraversion and Neuroticism are expected to be associated with better processing and recall of positive and negative emotional material respectively.

The results of the studies reveal the differential processing of extraverted individuals and high in neuroticism. The former complete more words in a positive way, make fewer mistakes with positive words, and remember them better. The opposite happens with the seconds that have facilities with negative words.

Gray's theory has been proposed to explain this association. For him, extraverted subjects would be impulsive and low in anxiety, and introverts would not be impulsive, but would score high in anxiety.

He proposes two neurophysiological systems for the Anxiety and Impulsivity dimensions: The BIS (Inhibition System behavioral) that would be the substrate of Anxiety, and the BAS (behavioral activation system) as support of the Impulsiveness.

Extraverts, being high in impulsivity, would have greater sensitivity to reward signals (BAS high), and introverts, having high anxiety, would be more sensitive to signs of punishment (high BIS).

It has also been suggested, regarding the relationship between Neuroticism and AN, that people who score high in it react more negatively to events that happen to them, causing them to frequently feel emotions negative. In any case, there may be an overlap between the measures of the Neuroticism dimension and those of AN (feelings of anxiety, guilt or worry), which characterize both.

Eysenck has been one of the few defenders of the traits that has been dedicated to explaining the neurophysiological mechanisms that could explain the differences between people. Although there is considerable support for his arousal theory, more research is required on Neuroticism and Psychoticism.

The theory has not dealt with a fundamental issue of personality such as motivation. He has not valued the differential impact that situations have on people. His way of understanding situations is too global.

His theory proposes an isomorphism between traits and brain systems. However, given the complexity of both the NS, and the interrelationships between behavior and systems neurophysiological, it is possible that any trait is influenced by different systems, and that any system contributes to more than one trait. Therefore, a more complete model is required that does not only focus on arousal.

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