Jean Piaget was the first theorist to conceptualize human development through a series of stages. His theory, cognitive development, dealt with more than just the development of intelligence. His focus was on how people react to knowledge and how, over the course of a lifetime , they interact with and use it (McLeod, 2012).
Piaget began his discussion of cognitive development at birth. The sensorimotor extended from birth through the period in life in which language is developed (McLeod, 2012). There are a number of substages in this phase of life that include the development of more complicated neurological and motor functions. As the child moves through these phases, he is able to distinguish himself for other objects in his environment (Piaget, 2010). The pre-operational stage begins around age two or when the child is beginning to speak. It stretches to age seven. This is the period during which a child has little understanding even concrete logic and is not able to make linkages between bits of information. (Piaget, 1977). The Concrete Operational stage begins at age seven and extends through age eleven. Children begin to think in a more adult manner and start to use appropriate logic (Piaget, 1977).The formal operational stage begins at 11 and extends through age 20. Children begin to develop an understanding of symbolic information and more abstract concepts. They can think about thinking and begin to problem solve using trial and error. Logical methods and processes begin to emerge (Piaget, 1977).
Piaget’s theory was based on a study of his own children and was later validated by incorporating a larger sample. However, his emphasis was on cognitive development but did not take into account the effects of environment and culture. Marcia (1966) developed a theory that explore the development of identity. While this was also a part of the exploration of Piaget and Erik Erikson, Marcia’s theory saw development as a set of “statuses” rather than places on a predictable continuum.
Marcia (1966) explored psychological development with an emphasis on the psychosocial development of adolescents and the development identity across the lifespan. While Erikson saw adolescence as time when the individual struggled to achieve identity and avoid confusion, Marcia understood adolescence as being a time in which the individual arrived at greater commitment to their identity in areas such as friendships, gender roles, relationships, politics, vocation and religion. He described two parts to the process of identity formation. First, the individual must experience a time of “crisis” in which new alternatives to old values are explored. The second phase involves commitment. Adolescents are involved in the crisis that eventually leads to choices in vocation and beliefs. The outcomes of a crisis in identity are dependent upon the individual’s exploration of alternative identities and whether or not the individual makes a choice between various identities.
Marcia’s theory incorporated four statuses that he saw as being part of ego identity formation. These statuses were Foreclosure, Identity Diffusion, Moratorium, and Identity Achievement. When the individual makes a commitment to a set of beliefs and occupations without consideration of alternative, the individual accepts certain beliefs and values without question. This status is identified as disclosure. In some cases, adolescents make a commitment to an identity that opposes another identity. This is called “negative identity”. However, once an individual’s identity is challenged by a crisis, the status of foreclosure cannot be achieved again.
Marcia’s theory offered an explanation for human development that sees the potential for development as extending throughout life. Further, development is not seen as being dependent upon time of life, but rather on the person’s motivation or ability to explore and make commitment to changes and growth. The path of development is not seen as unidirectional in that people may move from status to status as the result of fluctuations in their own level motivation and commitment (Marcia, 2010). Life transitions and stress in the context of psychosocial development. These fluctuations can occur in response to a number of contextual and situational factors. Marcia’s theory also allows for a better understanding of the way in which age, gender, race and culture can effect development. The classical stage theories of development like Piaget’s did not account for differences in societal expectations and requirements that interact with the biological development of physical and cognitive functions.