Infant temperament shows its flexibility

By BRUCE BOWER

January 23, 1999

Developmental investigations suggest that some babies exhibit a genetically inspired shyness that leads to an inhibited personality style later in life, whereas other infants display signs of an inbom sociability that heralds an outgoing nature.

However, these early bdhavioral styles often undergo noticeable shifts by age 4 1/2, according to a new report. Most babies at both behavioral extremes fall in a social middle ground by the time they become preschoolers, displaying neither pronounced shyness nor exuberance, contend psychologist Jerome Kagan of Harvard University and his colleagues.

Numerous childhood experiences may modulate the social disposition that infants start out with, Kagan's group theorizes.

"Our findings suggest that genes constrain temperament, they don't determine it," Kagan says.

The researchers studied 193 white, middle-class children. At 4 months of age, 74 of them had kicked, squirmed, and cried vigorously when they heard a tape recording of a woman's voice and received other types of simple stimulation. These youngsters were classed as hiah reactive, a response style linked in some studies to having a shy personality by adolescence.

The remaining 119 kids had remained largely calm and attentive during the same laboratory experiences. They were classed as low reactive, a designation for children deemed likely to become highly sociable and emotionally spontaneous with others.

The same children encountered further unfamiliar events in the laboratory at aaes 14 and 21 months. The scientists also assessed each youngster at 4 1/2 years old during interactions with an unfamiliar female experimenter and in play sessions with two unfamiliar children of the same age and sex. Parents were present at all times.

Preschoolers continued to display their infant temperaments to only a modest degree, the investigators conclude in the December 1998 CHILD DEVELOPMENT. Only about one-quarter of high-reactive infants were emotionally subdued and shy at 4 ‡ years old that was completely at odds with their infant temperament: Three high-reactive kids became spontaneous and sociable, and six low reactives became withdrawn and shy.

Nearly 70 percent of the children were neither extremely inhibited nor uninhibited as preschoolers, signifying that they had undergone moderate temperamental changes, the scientists assert.

Experiences that pull high-reactive infants out of their social shell are of particular interest, Kagan says. One crucial factor may be the presence of parents who encourage these kids to cope with their fears, he suggests.

The new results agree with findings from a developmental study directed by psychologist H. Hill Goldsmith of the University of Wisconsin-Madison.

"We observe a similar low degree of consistency for inhibited and uninhibited types from 30 months to 7 years of age," Goldsmith says.

Westen Ch. 14 Discussion Questions

1. What contribution can this research make to the "nature-nurture" debate?

2. What can parents do to help children who are particularly inhibited?

3. From this research, what conclusion could we draw about the relation between genes and temperament?