The Seattle Longitudinal Study

Adult cognitive development is one of the most important aspects in the study of human psychology, and the Seattle Longitudinal Study (SLS) is one of the world's longest running and influential studies of adult development and aging. Launched in 1956 by Warner Schaie, the SLS has followed multiple generations of adults for over five decades, generating an incredible database of numerous facets of biopsychosocial development from young adulthood through advanced old age.The Seattle Longitudinal Study traces the origins of the SLS, from the early discrepancies between cross-sectional and longitudinal findings that motivated the study's design and follows its evolution across successive waves of data collections. It guides readers through key research questions that have shaped the scientific understanding of adult development and aging and highlights the multidimensional influences on individual functioning and development across the adult lifespan. It also documents the study's major methodological contributions, including advances in sequential research designs, measurement invariance, and longitudinal modeling.This third edition features data from 2012 onwards, expanding the longitudinal coverage of the study to 56 years and increasing the interpretability of long-term aging trajectories. This edition provides a comprehensive summary of the works generated through decades of peer-reviewed research using SLS data and thus incorporates the most recent insights into how and why cognition, personality, neuropsychology, health, genetics, and lifestyle change throughout adulthood. Together these updates provide the most current and complete picture of the Seattle Longitudinal Study to date.This new edition is a valuable resource for researchers and practitioners specializing in adult development, aging, and adult education.