Temperamental Contributions to Inhibited and Uninhibited Profiles

A temperamental bias is currently defined as a behavioral profile with a partial origin in the child’s biology that varies among individuals. These biases, which appear early in development, are sculpted by experience into a variety of personality profiles. This chapter first describes possible genetic and nongenetic bases for temperamental categories, followed by a detailed presentation of the research on high- and low-reactive infants who are biased to become inhibited or uninhibited children. The chapter concludes with a discussion of the implications of these two temperaments to psychopathology and speculations on the temperamental variation among reproductively isolated human groups. A large number of questions remain unanswered. Perhaps the most critical is discovering the genes and resulting neurochemical or neuroanatomical features that contribute to the high- and low-reactive profiles.