temperament

Temperament refers to the individual differences in emotional reactivity and self-regulation that are biologically based and present from early development. It encompasses patterns of arousal, attention, and responsiveness to stimuli, and tends to show stability over time while being shaped by experience.

Etymology and historical theories: The term derives from Latin temperamentum, meaning mix or mixture of elements. In ancient and medieval medicine, temperaments were linked to bodily fluids (humors): sanguine, choleric, melancholic, and phlegmatic, each associated with distinct patterns of mood and behavior.

In modern psychology, temperament is distinguished from personality. Temperament is considered an inborn, relatively stable substrate of behavior that emerges early in life, whereas personality develops through learning and social influence. Researchers assess temperament in infancy and childhood using structured observations and caregiver reports.

Assessment and frameworks: Early models by Thomas and Chess described nine temperamental dimensions and three broad types (easy, difficult, slow-to-warm-up); later theories by Rothbart emphasized reactivity and self-regulation. In adults, temperament often maps onto traits such as extraversion and neuroticism, though measurement varies and the boundaries with personality are not fixed.

Applications and caveats: The concept informs pediatrics, education, and psychiatry, helping to tailor strategies to individual differences. Temperament is not destiny; environmental factors, parenting, culture, and learning experiences influence development and behavior. Cultural norms and measurement methods can affect how temperamental traits are observed and interpreted.