Harvard psychologist Jerome Kagan had a strong early belief about the debate between nature and nurture. He initially wanted to explore how the environment influenced children and was hesitant to accept that biology played a role. However, as he studied factors like family life and upbringing, he realized that there was more to understanding children’s temperaments, including shyness and sociability. Kagan and other researchers observed infants and toddlers over many years to find out what causes shyness. He noticed differences in infants from various cultures as early as three months old, which led him to conclude that temperament has a biological foundation.
In the late 1970s, Kagan began a series of studies focusing on “high reactive” and “low reactive” children. Researchers assessed infants as young as four months by observing their reactions to new experiences, such as unfamiliar toys or places. “High reactive” infants displayed distress, while “low reactive” infants remained calm. The most extreme cases from both groups were chosen for long-term studies, which continued for years, following many children into their teenage years and even adulthood.
Kagan’s research uncovered several important findings about shyness. He discovered that infants as young as three or four months could be categorized as high or low reactive. His studies indicated that shyness is linked to an overactive nervous system, with physical brain differences affecting how sensitive some individuals are to various stimuli. Kagan identified changes in the amygdala, the part of the brain responsible for responses to threats, as a key factor in these differences. Previously, shyness was viewed as a fixed personality trait, but Kagan’s long-term research suggested it is often hereditary and biological.
Moreover, Kagan found that shyness is not permanent. One surprising result of his studies was the ability of children to change their level of shyness over time. He noted that while some children who were very shy at age one might still be shy as teenagers, others would become less shy. Kagan mentioned in 1991 that from a group of ten very shy children, only three would remain very shy later in life. Those at the extreme ends of the spectrum were less likely to change.
In later follow-up studies, Kagan performed brain scans on some of the individuals he had identified as shy or highly reactive around 20 years earlier. Many of these individuals had become more confident and less fearful in adulthood. However, their brain scans still revealed an active and responsive amygdala, supporting Kagan’s theories about the biological nature of shyness. This indicated that while they developed social skills and coping mechanisms, their inherent sensitivity remained.
Understanding that shyness can be both an inherited trait and one that can change helps parents support their more sensitive children effectively. It shows that being shy is not a fixed trait but rather something that can evolve. What do you think about Kagan’s findings on shyness and temperament?
Sources:
Source: Upworthy, by Evan Porter