A well-known area of research by Piaget addresses processes and stages of cognitive development in children. This research was based on Piaget's theories of how an organism adapts to its environment, which he termed intelligence. Piaget saw behavior such as adaptation in controlled mental organization by the organism and designated these as "schemes." Piaget believes that the organism must achieve balance between the environment and schemes. Piaget designated this balance as "equilibration."
Professor Huit and Professor Hummel of Valdosta State University state that Piaget theorized about how organisms are born with schemes called reflexes. In humans, the reflexes are replaced with organized schemes for adaptation. The individual attempts to adapt to the environment through two processes: assimilation and accommodation. Assimilation involves transforming the environment so as to fit the cognitive structures of the individual. Accommodation involves the change of cognitive structures to suit the environment. Schemes evolve as the individual develops. These sophisticated schemes are called structures.
Piaget theorizes that cognitive development can be divided into four stages, which in turn can be divided into smaller parts. In infancy the individual is in the sensormotor stage. This can be divided into knowledge, memory, mobility and language development. When individuals advance from toddler to early childhood, they enter the pre-operational stage. The individual will demonstrate intelligence through the use of language and symbols. Imagination and memory develop. Thinking is egocentric, non-logical and non-reversible.
The concrete operational stage covers the period from the elementary years to adolescence. The sub-stages in this stage involve perception of the physical world and include grasping concepts such as volume, area, weight, mass, liquid, length and number. Children demonstrate intelligence through manipulation of symbols as they relate to concrete objects. Reversible mental actions develop. Thought becomes less egocentric. The formal operational stage occurs as the individual moves from adolescence to adulthood. The individual uses symbols related to concrete concepts. Adolescents return to egocentric thought and may or may not demonstrate formal thought as they enter adulthood.
Professor DeVries of the University of Northern Iowa notes that Piaget's social theories focus on intellectual, socio-moral, affective and personality development, Dr. DeVries sees parallels between socio-moral development and intellectual development. First, Piaget's theories indicate that there was a parallel between development of knowledge related to the world of objects and psychosocial knowledge. Second, social bonds affect intellectual and moral development. Finally, equilibration as a self-regulating process can be identified for socio-moral and intellectual development.