Originally published in 1975, this volume deals with animals and human infants. The chapters reflect a mixture of issues and problems ranging from the significance of sucking responses in the newborn, the development of memory, effects of rearing conditions in monkeys, and brain damage in animals, to processes underlying abnormal development of language. While it appears the issues are diverse, there is actually a common theme. One question is posed: How and why does normal development fail to occur in some human infants? The chapters show that there are many causes of aberrations: physical or psychological trauma, disease, inheritance, and drugs. Although one may be primary, "multiple causation" would still appear to be a sound principle in developmental pathology.