Chapter 1 Introduction

This document provides an overview of theories and research on adolescent development. It discusses early Greek philosophers' focus on cognitive ability and self-awareness in adolescents. It then outlines major theorists like Hall, who studied biological and social influences, and Darwin who emphasized environmental influences over biological ones. Freud's psychosexual stages of development and Erikson's psychosocial stages are summarized. Piaget and Vygotsky's cognitive theories on ordered stages of thinking are covered. The document also discusses Bandura's social learning theory and Bronfenbrenner's ecological systems theory of environmental layers influencing development.