Regression periods play a central role in the psychological development of the human baby. Studies of infants have identified 10 periods of regression, or a return to a high frequency of mother-infant contact, within the first 20 months of life. These periods of emotional insecurity in the child signal forthcoming periods of developmental advance and the emergence of an array of new skills as a consequence of parent-infant conflict over body contact and the renegotiation of old privileges.
Although the basic idea in this book is an old one, the authors believe that regression periods...