Final answer:
Eysenck's PEN model emphasizes the biological basis of personality, comprising three dimensions: extroversion/introversion, neuroticism/stability, and later, psychoticism/superego control, with a focus on genetics and temperament.
Step-by-step explanation:
Eysenck's PEN model is a significant contribution to the field of personality psychology. Psychologists Hans and Sybil Eysenck proposed that personality is largely governed by biology, suggesting an inherent genetic influence on individual differences in temperament. Initially, the Eysencks presented two primary dimensions of personality: the extroversion/introversion spectrum and the neuroticism/stability spectrum. They later included a third dimension called psychoticism versus superego control. The Eysenck's model pay particular attention to the biological and genetic underpinnings of these traits.
People high in extroversion are described as sociable and outgoing, while introverts prefer solitude. Similarly, individuals with high levels of neuroticism tend to experience more anxiety and emotional instability, unlike their stable counterparts. Eventually, the model was expanded to include psychoticism as a trait characterized by aggressiveness and a lack of empathy, contrasted with individuals who have high superego control and are more empathetic and conventional. This model provided a framework to categorize people into four quadrants, often likened to the four temperaments recognized by ancient Greeks: melancholic, choleric, phlegmatic, and sanguine.