We began the weekend with Dr.Nancy Snidman, a colleague of Dr. Jerome Kagan who talked to us about temperament. She defined temperament as “what a child brings to the interaction with the environment to create personality”, pointing out that nowadays we tend to talk about “individual differences” instead of temperament, but that individual differences tends to be a “blend of temperament and environment”. Nancy talked to us about the differences in reactivity of children related to different thresholds of reactivity in the amydala. In their study of the amydala output effects, such as sympathetic responses, output to the larynx (crying), and output to the skeletal motor system, the research group identified a group of “timid” children who had inherited a low threshold of reactivity of the amydala.
It turns out that if you look at the sensory integration scale and the temperament scale, you find a lot of overlap, and some people think they are not so different. Nancy said that if part of your definition of sensory integration disorder is that there is an overwhelming response to sensory information that the child is born with, you could call it temperament.
Nancy showed us videos of two 4-month old infants responding to a mobile. One baby was highly reactive to the stimulus, and the other was not. The research group chose babies who were high reactive and low reactive in terms of motor behavior and crying modes of reactivity and they followed them over time. Starting at 21 months the researchers saw a lot of consistency.
The high reactive girls at 21 months started to look shy, a trait that diminished later on. As the children grew older, the best behavioral indicator of their status was spontaneous smiles and comments. The cognitive style related to high reactivity is associated with high levels of response inhibition and over control. The most cohesive group was low reactive boys.
Socialization differences did have an impact. Interestingly, the low reactive boys tended to seek out risky behavior, whereas the (more “timid”) high reactive boys were often encouraged by their parents to get into sports, against their initial inclination. When these high reactive boys were older they would often end up in individual sports such as swimming, which is a team sport but may avoid some of the rough and tumble aggression characterizing the others. As the kids got older, it was novelty that would trigger the threat. In preschool, when they became familiar with the school, they were fine. There were some high reactive boys who were doing very well in high school but couldn’t manage the transition (the novelty) to college.
Nancy sees temperament as underlying all that gets created in the interaction between the individual and the environment. What is the environment that the child finds him or herself in? If you were counseling parents, you might think – in the case of a high reactive child – to suggest that the parent take more time with transitions. In the case of a low reactive boy, you might try to protect the child against a tendency towards risky behavior.