Home > Encyclopedia of Psychology > Nancy Bayley

1899-1994
American developmental psychologist known for her "Scales of Mental and Motor Development."

Nancy Bayley was a pioneer in the field of human development. She devoted her life to documenting and measuring intellectual and motor development in infants, children, and adults. Her studies of the rates of physical and mental maturation have greatly influenced our understanding of developmental processes. Her "Bayley Scales of Mental and Motor Development" are used throughout the world as standardized measurements of infant development. Bayley was the recipient of numerous honors and awards throughout her career. In 1966, she became the first woman to win the Distinguished Scientific Contribution Award of the American Psychological Association (APA).

The third of five children of Prudence...