ABSTRACT
This chapter considers the predictive relation between the behavioral profile at four months and behavior in the second year. Although the predictive power of the four-month classifications was slightly better for children with very low fear scores than for those with high scores, the procedures were designed specifically to elicit fear. High reactive infants were vulnerable to both kinds of fear reactions, reflecting a physiological state that renders them especially susceptible to both distress and avoidant responses to discrepancies. The dramatic difference between high and low reactive infants in fear of the unfamiliar in the second year adds credibility to the idea that inhibited and uninhibited children inherit different thresholds of excitability in the amygdala and its circuits. If the home environment does not partially extinguish that habit, the behavior should persist and children could be expected to react to the unfamiliar events encountered in the laboratory with crying and avoidance.
