Early‐ and later‐developing shyness in children: An investigation of biological and behavioral correlates

Early theoretical work by Buss (1986a, 1986b) posited that there is an early-developing fearful shyness that emerges during toddlerhood, and a later-developing self-conscious shyness that emerges during early childhood. It has been theorized that early-developing shyness is related to fear, rooted in inherited biases, and manifests in contexts of social novelty, whereas later-developing shyness is related to self-conscious emotions, may result from social ridicule or poor social skills, and manifests in contexts of social exposure. Despite the hypothesized correlates of these shyness subtypes, this theory has not been empirically tested in children. We tested 96 children aged 5 to 10 years old and classified them into three groups: early-developing shyness (n = 28; M_AgeOnset  = 2.4 years), later-developing shyness (n = 19; M_AgeOnset  = 4.8 years), and non-shy (n = 49). Findings revealed that children with later-developing shyness had the highest relative cortisol responses in the context of self-presentation, highest levels of embarrassment, and lowest social skills relative to the other groups, while children with early-developing shyness displayed the highest relative resting right frontal brain asymmetry (a neural correlate of fear) relative to the other groups. These preliminary findings provide partial empirical support for the previously theorized correlates and distinction of early-developing and later-developing shyness in childhood.