Stages of Human Development

Clearly defining stages of human development can be a difficult task at times; some consider human development to be rooted in one's physical development, while others consider it to be cognitive, emotional, or psychosocial. However, breaking down the stages of human development into their most rudimentary forms provides a clear understanding of how humans themselves develop.

You can easily illustrate the stages of human development by breaking them down into the time of life that one is looking at or by the theorist that outlined the stages. Both was are excellent for researching and writing on human development.

One type of Development - Human Fetal Development

The first stage of human development is conception, when the sperm permeates the egg and the process of reproduction has started. The second stage occurs between the first and third days after conception and is marked by the creation of a zygote. A blastocyst is created in the third stage, the time between the second day and the second week; this is when the fertilized egg is implanted in the woman's uterine wall. The blastocyst develops into an embryo through the eighth week; this is where some of the rudimentary signs of life can be found, such as simplistic heartbeats. After the ninth week of development in the womb, the product is termed a fetus, and will remain this way until birth. During these 31 weeks, the fetus develops all the physical elements necessary for human life, including cardiac functioning, lung development, skeletal and muscular elements, and cognitive functioning. The fetus is considered viable, that is, it can survive outside the womb, after the 24th week of gestational development.

Development of the Human Mind

Another type of development for humans is post-infancy and is child development. More specifically, development of the mind in a child is a critical phase in human development. Jean Piaget attempts to explicate the origins of the mind in terms of "species-specific biological reflexes" and the spontaneous reactions that infants initiate with their surroundings.

In Jean Piaget"s text, The Origins of Intelligence in Children (1969), Piaget outlines his six stages of development. These stages include:

• Stage 1-The Use of Reflexes: In this stage, Piaget notes that the infant is endowed with specific biological mechanisms that allow him to interact with the world around him. However, Piaget makes the observation that even in the first few days of life, the infant must learn how to control or accommodate these biological reflexes such that he can meet his biological needs.
• Stage 2-The First Acquired Adaptations: Piaget noted that at approximately three months of age, the infant began to acquire new skills that enabled him to better meet his biological needs. To illustrate this point, Piaget refers to the variances in sucking that occur when the infant chooses to suck his thumb for comfort. Piaget contends that these adaptations are learned.
• Stage 3-Prehension of Visual Objectives: This stage occurs between thee and eight months and is identified by the empirical recognition of behavior patterns that are consistent with the presentation of visual stimuli. At this point the infant is beginning to order information such that visual stimulation promulgates a specific response.
• Stage 4-Application of Known Means: In this stage of development, which occurs between 8and 9 months, the infant is able to apply schemata to new situations. This stage of development is where applied intelligence begins to manifest as the infant begins to learn how to apply what has been learned to new stimuli.
• Stage 5-Discovery of New Means: This stage of development begins in the second year of life and is recognized by the willingness of the infant to experiment with new actions for problem solving.
• Stage 6-Invention of New Means-This stage represents the mental combination of different schemata in dealing with new environmental stimulus. This stage occurs between the ages of 18 and 24 months.

L.S. Vygotsky

Looking specifically at the stages of development that have been identified by L.S. Vygotsky, Green and Piel go on to note that there are three phases which are comprised of several stages each. As described by Green and Piel, the phases of human developed outlined by Vygotsky are characterized by the specific mental processes that are being carried out by the child. The phases and stages are as follows:

• Phase 1 - This phase is recognized by egocentric rhetoric and attempts by the child to make associations through language. Phase 1 have three stages which begin with trial and error and end with more ordered thinking through grouping by similarities.
• Phase 2 - In this phase, similarities and differences between objects can be clearly recognized by the child. This phase contains five stages, which begin with the child noting single properties in common between objects and ending with the child being able to group objects by abstract qualities.
• Phase 3 - In this phase, the child is able to grasp concepts. This phase is comprised of three stages that begin with unifying parts with a whole and end with the development of "rule governed generalizations".

Erik Erikson

Erikson was able to develop a stage theory of development that encompassed the entire scope of the lifespan. Erikson noted eight specific stages that ranged from infancy to old age. The stages as identified by Erikson are as follows:

1. Infancy - Basic trust versus basic mistrust
2. Early Childhood - Autonomy versus shame and doubt
3. Play Age - Initiative versus guilt
4. School Age - Industry versus inferiority
5. Adolescence - Identity versus identity confusion
6. Young Adulthood - Intimacy versus isolation
7. Adulthood - Generactivity versus stagnation
8. Old Age - Integrity versus despair

As noted by Erikson in his observations, the specific stages of development are marked by a particular ego conflict. If the conflict can successfully be resolved in the context of maturation, the individual moves on to the next stage of development. If the conflict cannot be resolved, the individual becomes dysfunctional in his or her behavior. This method for understanding the conflicts experienced by the ego also represent a clearly pathway for the professional to diagnose dysfunction and also to determine the specific issues promulgating distress for the individual. Only through the resolution of each of the ego crises can the individual develop on a liner path without any sort of mental disturbance.