Thanks to suggestions from students who used the fifth edition of our text and the insightful comments of reviewers, we have made the following substantial changes in the sixth edition:

• An innovation from the previous edition, An Informed View, contains a World Wide Web icon that will prompt you to visit the text's web site for additional information. We have added a number of new and more interesting sites.
• In addition to appearing at the end of the text in the glossary, definitions of key terms now appear within the margins of the text. This enhancement makes it easier for students to identify important terms and study them in preparation for exams.
• We have continued to add new examples of the biopsychosocial approach in this edition.
• Because we believe that the quotations that appear in each chapter in our book set the tone for that chapter, we have provided one as an opening, along with a vignette about human development, in each chapter.
• Earlier in this preface we mentioned that development is a lifelong process, which implies that life-span psychology books must constantly change to accommodate fresh insights into the developmental process. To meet this challenge, we have made the following key changes in our chapters:

Chapter 1. Lifespan Psychology: An Introduction

• We have significantly rearranged the introductory material to bring our readers immediately into the reality of what passage through the lifespan means.
• The major change is the addition of a section entitled Changing Views of the Lifespan. This historical discussion of how ideas about human development changed over the years should give our readers a rich and thoughtful interpretation of human development.

Chapter 2. Theories of Development: Interpreting the Lifespan

• The section on Evolutionary Developmental Psychology has been substantially expanded.

Chapter 3. The Biological Basis of Development

• The discussion on the Human Genome Project has been expanded and updated.
• The biological data in the chapter have also been updated to reflect new ideas that have appeared since the last edition (cloning, DNA, etc.).

Chapter 4. Pregnancy and Birth

• Substantial revisions have been made to this chapter, particularly with regard to the nervous system. Beginning with the embryonic period, new data, new examples, and new diagrams greatly enhance the discussion.
• In the section on maternal emotions, the classic work of Ruth Rubin has received considerable coverage to enrich the presentation of maternal influences.
• There is a new section devoted to cultural variations in the birth process.
• The discussion of prematurity has been increased and the groundbreaking work of Heidi Als is presented in greater detail.

Chapter 5. Physical and Cognitive Development in Infancy

• The introduction to Chapter Five has been rewritten to reflect different views of infancy in a manner that brings our readers into the infant world as soon as possible.
• The most significant changes in this chapter relate to brain development. A box entitled Building the Brain Structures adds a new, development dimension to the discussion.
• New work on neuronal communication with new diagrams has also been added.

Chapter 6. Psychosocial Development in Infancy

• A new introduction more meaningfully brings readers into the chapter's content. Statements by leading figures—Bowlby, Ainsworth—link their ideas more tightly to the chapter's discussion.
• Jerome Kagan's new work—The Long Shadow of Temperament—has been added to the analysis of temperament. Stressing biological aspects, it is a controversial viewpoint, one that deserves attention.

Chapter 7. Physical and Cognitive Development in Early Childhood

• A new introduction connects the chapter's content more tightly to the chapter's beginning (comments by John Flavell, Berry Brazelton, Steven Pinker).
• New and more developmental data on the brain has been added.
• Several illustrations have been added to the presentation of Kellogg's ideas on artistic development so that readers can identify the developmental features of children's drawings.
• The theory of mind section has been changed to more precisely indicate how children represent their world.

Chapter 8. Psychosocial Development in Early Childhood

• The introduction to the chapter was rewritten (using the early years of Mahalia Jackson) to emphasize the importance of culture and to bring readers into the chapter's material more quickly and to stress the level of development emphasized in the chapter.
• The day care section was reworked to include recent studies and to summarize conclusions concerning cognitive and psychosocial outcomes of early child care.

Chapter 9. Physical and Cognitive Development in Middle Childhood

• The opening to the chapter was redone to illustrate the growing cognitive competence of middle childhood children. The young Thomas Edison, always popular, was used as an example.
• The physical development section was changed to incorporate new data about brain development during these middle childhood years.
• An entirely new section devoted to exceptional children was added to the chapter, including implications of legislation (IDEA, for example).
• The notion of literacy—including such categories as basic, scientific, technological, etc.—was introduced in the language development section together with the belief that knowledge of development is a major necessity for matching children with their books.

Chapter 10. Psychosocial Development in Middle Childhood

• A substantial section on ADHD has been added to the discussion of impulse control.
• The work on stress has been notably revised to incorporate the ideas of Abraham Maslow whose ideas have been recently given more and more attention in developmental psychology. This adds greater practicality to the effects of stress.

Chapter 11. Physical and Cognitive Development in Adolescence

• We have added sections on changing attitudes toward menarche.
• Cultural identity is an important part of this chapter on adolescence.
• A new look at the relationship between emotions and brain development is offered.
• There is a complete new section on types of mental disorders.
• We have included a new box on high stakes testing.

Chapter 12. Psychosocial Development in Adolescence

• Father absence and the role of parents are updated.
• We have incorporated a new segment on Internet bullies.
• The heritability of homosexuality and lesbianism are considered.
• Statistics on illicit drug use (mainly Ecstasy, LSD, and PCP), excessive alcohol use, and cigarette use are updated and discussed.
• Gang behavior, the use of guns, and other risk factors in youth violence are considered anew.

Chapter 13. Physical and Cognitive Development in Early Adulthood

• The "adultoid" is a new concept in this chapter.
• We have added a new box on choosing a career.
• There is a revised look at the role of fathers in raising children.
• We have added a new box on working mothers and work-family conflicts.
• Home-based work patterns are reviewed.
• We introduce a new box on effects of culture on research findings in general.

Chapter 14. Psychosocial Development in Early Adulthood

• New information on cohabitation is included.
• The discussion of networks of non-relatives and friends, as well as mother-daughter relationships, has been revised.
• Sternberg's theory of love is discussed in more depth.

Chapter 15. Physical and Cognitive Development in Middle Adulthood

• Food imbalances are the focus of a new section.
• We offer a new segment on the causes of decreased ability to smell.
• Information on menopause and sex is presented in greater detail.
• Our coverage of hormone replacement therapy has been substantially enlarged.
• Effects of "spillover" and burnout are given additional consideration.

Chapter 16. Psychosocial Development in Middle Adulthood

• Coping with debilitating anxiety receives added attention in the section on stress in this chapter.
• Marital satisfaction and our ability to predict divorce are given more attention.
• Important new research on the middle-aged person's relationships with aging parents is presented here.
• New research on dual-career households is covered.
• A completely updated continuous traits theory takes the place of Costa and McCrae's earlier ideas on this aspect of personality development.

Chapter 17. Physical and Cognitive Development in Late Adulthood

• We provide new data on the aging gastric system.
• Startling new information on Alzheimer's and memory, as well as new views on Alzheimer's and innovative educational techniques, are presented in this Chapter on elderly development.
• The effects of aging on mental ability in general are also covered.

Chapter 18. Psychosocial Development in Late Adulthood

• Sexuality in the elderly receives fresh attention in this chapter.
• The discussion of treatments for erectile dysfunction, a topic that has often been in the news lately, has been updated.
• We include a new segment on the relationship between long-standing marriages and illness.

Chapter 19. Dying and Spirituality

• In a new section, we look at differences among suicide attempters.