Piaget's Four Stages of Cognitive Development Explained

Introduction

One of the most influential theorists discussing cognitive development throughout the lifespan is Jean Piaget. The cognitive development of children is of particular interest from the perspective of a budding pediatric psychologist. Piaget's model, while not without its critics, has stood the test of time and remains the foundational model of cognitive development presented in developmental psychology textbooks, as well as a general framework for research and theory development in the field (Egan, 2012). Piaget's overall stage theory is briefly discussed in this paper.

Piaget's initial research subjects were children from birth to seven years of age, though he also studied individuals through adulthood. In actuality, Piaget's early subjects were his own children; later he studied children of different ages under laboratory conditions (Burman, 2008). In essence, Piaget's methods were correlational and consisted mostly of a combination of observation and interview. He relied primarily on presenting the child with a task, observing how the child solved it, and then asking questions about the child's reasoning process. When studying play, a child might be given a toy to observe, or placed in a room full of toys with other children. For other cognitive principles, children were presented with different stimuli — for example, a tall thin glass and a shorter, stout one (both holding equal amounts of liquid) — and asked to decide which held more water. This task tested the concept of conservation (Berk, 2011; Burman, 2008).

The results of Piaget's research yielded a stage model of cognitive development comprising four major stages (Berk, 2011): the Sensorimotor stage (birth to two years of age); the Preoperational stage (two to approximately seven years of age); the Concrete Operational stage (seven to approximately eleven years of age); and the Formal Operational stage (eleven years and beyond). Each stage is marked by a particular style of thinking and reasoning, and some stages are further divided into sub-stages. A brief explanation of each stage follows (Berk, 2011; Egan, 2012).

Sensorimotor Stage: Birth to Approximately Two Years

Many striking changes in behavior occur in the first two years of a child's life. In this stage, the child is focused on the here and now of its existence because it cannot consistently form mental representations of things or project into the future. Objects exist only when the child can actually sense them; when they are absent from the child's immediate experience, they are effectively nonexistent. According to Piaget, during the sensorimotor stage the child experiences the world through its senses and through movement. Children are extremely egocentric at this stage, meaning they are unable to experience the world through perspectives other than their own. The sensorimotor stage is divided into six sub-stages:

1. Simple reflexes (birth to one month). Characterized by reactions to the environment through simple reflexes such as rooting and sucking.

2. Primary circular reactions (one to four months). A circular reaction occurs when the infant attempts to repeat activities that produce a desirable outcome. Primary circular reactions refer to the infant's tendency to repeat bodily actions in this manner. Typically, the action first occurs by accident and the child then attempts to reproduce it due to its pleasing effect. Thumb-sucking is a classic example.

3. Secondary circular reactions (four to eight months). Children develop an awareness of things outside their own body and begin to focus on external objects. For example, a child who accidentally shakes a rattle and then repeatedly shakes it again to hear the noise demonstrates a secondary circular reaction.

4. Coordination of secondary circular reactions (eight to twelve months). At this point, children begin to use existing knowledge to produce an intended effect (intentionality), rather than accidentally discovering outcomes. An example is a child using a stick to reach a distant object.

5. Tertiary circular reactions (twelve to eighteen months). Children begin to explore new possibilities. For example, a child may pick up a spoon, drop it on the floor, and wait to hear the sound it makes. The child may also begin banging various toys or objects to listen for the different sounds produced. At this sub-stage, children also begin to develop a sense of object permanence, and may search for a hidden object — though only in the last location where they saw it.

6. Internalization of schemes (eighteen to twenty-four months). This sub-stage represents a transition to symbolic thought — the ability to internally represent events that are not actually being perceived. Here, the child exhibits deferred imitation: the ability to imitate an action in the absence of a model who is currently demonstrating that action.

Preoperational Stage: Two to Seven Years

In this stage there is a marked improvement in the child's understanding of the world. Children can mentally represent information but cannot yet integrate it with other knowledge in a fully logical manner. As a result, the development of true logical operations has not yet taken place.

The preoperational stage is divided into two sub-stages:

1. Preconceptual thinking (two to four years). In this sub-stage, the child understands some properties of classes of objects but not all of them. For example, a child may refer to every object with four legs as "a chair." Children also demonstrate animistic thinking, attributing lifelike characteristics to inanimate objects. Transductive reasoning — reasoning based on concrete perceptions rather than logic — is another hallmark of this sub-stage. For instance, a child may believe that pizzas are shaped like triangles because the slices served to them are triangular, without understanding the shape of the whole pie.

2. Intuitive thinking (four to seven years). Children in this sub-stage have largely ceased using transductive reasoning, and their thinking is more logical, though it is still guided by perception rather than abstract logic. For instance, children at this stage lack conservation — the understanding that certain attributes of objects remain unchanged unless something is added to or removed from them. A child may therefore believe that a tall, thin glass of water holds more water than a short, stout glass containing the same amount. Children also remain egocentric at this sub-stage.

References

Berk, L. E. (2011). Infants, children, and adolescents (7th ed.). Boston: Allyn and Bacon.

Burman, J. T. (2008). Experimenting in relation to Piaget: Education is a chaperoned process of adaptation. Perspectives on Science, 16(2), 160–195.

Egan, K. (2012). Education and psychology: Plato, Piaget and scientific psychology. New York: Routledge.