Adoption studies can predict shyness in adopted children from the biological mother's sociability. Extremely inhibited children show physiological differences from uninhibited children, including higher and more stable heart rates. Patterns of social passivity or inhibition are remarkably consistent in longitudinal studies of personality development. Despite this evidence, most researchers emphasize that genetic influences probably account for only a small proportion of self-labeled shyness. Even hereditary predispositions can be modified.
Shyness can be a normal, adaptive response to potentially overwhelming social experience.
By being somewhat shy, children can withdraw temporarily and gain a sense of control. Generally, as children gain experience with unfamiliar people, shyness wanes. In contrast, children who exhibit extreme shyness which is neither context-specific nor transient may be at some risk. Shy children have been found to be less competent at initiating play with peers. Such factors negatively affect others' perceptions.