There are four main developmental theories; Biophysical, Psychosocial, Cognitive and Moral development. These theories help to explain and predict human behaviour, giving a model of how and why people become who they are.
Biophysical development is the process of biological maturation. It compares the changes that occur as an infant grows into adulthood and attempts to describe why our bodies age, this process is based on recognised norms. Arnold Gesell initiated the study into physical growth and change. Through extensive observations Gesell developed norms that are still recognised in childhood development today. Fundamental to his theory was that, we grow according to our own genetic blueprint and pace, going as far as to say that our biological body determines our behavioural development. Growth is directed by gene activity; however environmental factors can modify the pattern in which we develop. Biophysical development also includes non-genetic cellular theories which look at the cell rather than DNA, the theory that our body just wears out. It also looks at the Physiological theories of aging, the theory that a single organism is broken-down and impairs the performance of the physiological control mechanisms.
Psychosocial development emphasizes the idea that our personality, thinking and behaviours are intrinsically social. Many theorists have spent their life time trying to understanding how we become successful human beings. Erik Erikson's theory of psychosocial development proposed that we go through a series of crises from infancy to late adulthood that life is a serious of lessons and challenges which help us to grow and that success or failure in dealing with these conflicts can impact on our overall functioning. Erikson explains eight stages through which a healthily developing human should pass. In each stage the person confronts, and hopefully masters, new challenges. Each stage builds on the successful completion of earlier stages. The...