Jean Piaget (1896-1980) was one
of the most influential
researchers in the area of developmental psychology during
the 20th century.
Piaget originally trained in the areas of biology and philosophy and considered himself a "genetic epistemologist." He was
mainly interested in the biological influences on "how we come to know." He
believed that what distinguishes human beings from other animals is our ability to do
"abstract symbolic reasoning." Piaget''s views are often compared with those of
Lev Vygotsky
(1896-1934),
who looked more to social interaction as the primary source of cognition and behavior.
This is somewhat similar to the distinctions made between
Freud
and Erikson in terms of the development of
personality. The writings of Piaget (e.g., 1972, 1990; see Piaget, Gruber, & Voneche)
and Vygotsky (e.g. Vygotsky, 1986; Vygotsky & Vygotsky, 1980), along with the work of
John Dewey (e.g., Dewey, 1997a,
1997b), Jerome Bruner
(e.g., 1966, 1974) and Ulrick Neisser (1967) form the basis of the constructivist theory of learning and instruction.
While working in
Binet''s
IQ test lab in Paris, Piaget became interested in how children think. He noticed that
young children''s answers were qualitatively different than older children which suggested
to him that the younger ones were not dumber (a quantitative position since as they got
older and had more experiences they would get smarter) but, instead, answered the
questions differently than their older peers because they thought differently.
There are two major aspects to his theory: the process of coming to know and the stages
we move through as we gradually acquire this ability.
Process of
Cognitive Development. As a biologist, Piaget was interested in how
an organism adapts to its
environment (Piaget described as intelligence.) Behavior
(adaptation to the environment) is controlled through mental organizations called schemes
that the individual uses to represent the world and designate action. This adaptation is
driven by a biological drive to obtain balance between schemes and the environment
(equilibration).
Piaget hypothesized that infants are born with schemes operating at birth that he
called "reflexes." In other animals, these reflexes control behavior throughout
life. However, in human beings as the infant uses these reflexes to adapt to the
environment, these reflexes are quickly replaced with constructed schemes.
Piaget described two processes used by the individual in its attempt to adapt:
assimilation and accomodation. Both of these processes are used thoughout life as the
person increasingly adapts to the environment in a more complex manner.
Assimilation is the process of using or transforming the environment so that it can be
placed in preexisting cognitive structures. Accomodation is the process of changing
cognitive structures in order to accept something from the environment. Both processes are
used simultaneously and alternately throughout life. An example of assimilation would be
when an infant uses a sucking schema that was developed by sucking on a small bottle when
attempting to suck on a larger bottle. An example of accomodation would be when the child
needs to modify a sucking schema developed by sucking on a pacifier to one that would be
successful for sucking on a bottle.
As schemes become increasingly more complex (i.e., responsible for more complex
behaviors) they are termed structures. As one''s structures become more complex, they are
organized in a hierarchical manner (i.e., from general to specific).
Stages of Cognitive Development. Piaget identified four
stages in cognitive
development:
Sensorimotor stage (Infancy). In this period (which has 6 stages), intelligence
is demonstrated through motor activity without the use of symbols. Knowledge of the world
is limited (but developing) because its based on physical interactxperiences.
Children acquire object permanence at about 7 months of age (memory). Physical development
(mobility) allows the child to begin developing new intellectual abilities. Some symbollic
(language) abilities are developed at the end of this stage.Pre-operational stage (Toddler and Early Childhood). In this period (which has
two substages), intelligence is demonstrated through the use of symbols, language use
matures, and memory and imagination are developed, but thinking is done in a nonlogical,
nonreversable manner. Egocentric thinking predominatesConcrete operational stage (Elementary and early adolescence). In this stage
(characterized by 7 types of conservation: number, length, liquid, mass, weight, area,
volume), intelligence is demonstarted through logical and systematic manipulation of
symbols related to concrete objects. Operational thinking develops (mental actions that
are reversible). Egocentric thought diminishes.Formal operational stage (Adolescence and adulthood). In this stage, intelligence
is demonstrated through the logical use of symbols related to abstract concepts. Early in
the period there is a return to egocentric thought. Only 35% of high school graduates in
industrialized countries obtain formal operations; many people do not think formally
during adulthood.
Many pre-school and primary programs are modeled on Piaget''s theory, which, as stated
previously, provides part of the foundation for
constructivist
learning. Discovery learning and supporting the developing interests of the child are
two primary instructional techniques. It is recommended that parents and teachers
challenge the child''s abilities, but NOT present material or information that is too far
beyond the child''s level. It is also recommended that teachers use a wide variety of
concrete experiences to help the child learn (e.g., use of manipulatives, working in
groups to get experience seeing from another''s perspective, field trips, etc).
Piaget''s research methods were based primarily on case studies
.
While some of his ideas have been supported through more correlational and
experimental methodologies, others have not. For example, Piaget believed that biological
development drives the movement from one cognitive stage to the next. Data from
cross-sectional studies of children in a variety of western cultures seem to support this
assertion for the stages of sensorimotor, preoperational, and concrete
operations ( Renner, Stafford, Lawson, McKinnon, Friot & Kellogg,
1976)