Temperament refers to the innate, biological aspects of an individual’s behavioral style, influencing how they react to the world. These characteristics are observable early in life and contribute to individual differences in children. Understanding a child’s temperament provides insights into their unique needs and environmental interactions. The New York Longitudinal Study pioneered the identification of distinct temperament categories.
The New York Longitudinal Study and Temperament
The New York Longitudinal Study (NYLS), initiated in 1956 by psychiatrists Alexander Thomas and Stella Chess, was a long-term observation of children from infancy into adulthood. This research aimed to understand how individual differences in behavioral style emerge and influence development. Thomas and Chess used detailed parental interviews and direct observations to gather data on various behavioral dimensions.
Their goal was to explore temperament as an inborn quality, distinct from learned behaviors or personality traits. The study assessed nine dimensions of temperament, such as activity level, rhythmicity of bodily functions, adaptability, mood, and intensity of reactions, to create a behavioral profile for each child. These dimensions categorized children into different temperamental groups, highlighting the inherent variations in how children interact with their surroundings.
The “Easy” Temperament
Children with an “Easy” temperament display a positive mood and cheerful disposition. They establish regular routines quickly, including predictable eating and sleeping patterns, which often makes their care relatively straightforward. Approximately 40% of children in the NYLS exhibited these characteristics.
These children adapt readily to new situations, people, and changes in their environment. When faced with frustrations, their reactions are usually mild to moderate, and they recover quickly. An easy child might readily accept a new food or adjust to a new caregiver without distress.
The “Difficult” Temperament
Children with a “Difficult” temperament often have a negative mood, expressing irritability or fussiness. Their biological routines, such as sleeping and eating, are irregular, making them less predictable. This temperament was observed in about 10% of the children in the NYLS.
These children adapt slowly to new situations and changes, often reacting with strong negative responses. Their emotional reactions are intense, and they may experience frequent crying episodes or temper tantrums. A difficult child might strongly resist routine changes or react intensely to new foods or environments.
The “Slow-to-Warm-Up” Temperament
The “Slow-to-Warm-Up” temperament describes children with a low activity level and a cautious approach to new experiences. Initially, they hesitate or withdraw when encountering unfamiliar people or situations. This temperament was identified in approximately 15% of the children studied.
Despite their initial hesitation, these children gradually adapt and become engaged with sufficient time and repeated exposure. Their moods are mildly intense, and they may appear shy or reserved at first. A slow-to-warm-up child might observe a new activity before gradually joining, becoming comfortable once the situation feels safe.
The “Mixed” or “Average” Child
The New York Longitudinal Study recognized that not all children fit neatly into the three primary temperament categories. A substantial portion of children, approximately 35%, displayed a mix of characteristics or did not align with a single category. These children are often referred to as having a “mixed” or “average” temperament.
This group represents a normal variation in child development, indicating that temperament exists on a spectrum rather than as rigid classifications. This category highlights the diversity of temperamental profiles in the population. Many children exhibit a unique combination of qualities, making them adaptable.