Cognitive Development Theory: What Are the Stages?

Cognitive development is the process by which we come to acquire, understand, organize, and learn to use information in various ways. Cognitive development helps a child obtain the skills needed to live a productive life and function as an independent adult.

The late Swiss psychologist Jean Piaget was a major figure in the study of cognitive development theory in children. He believed that it occurs in four stages—sensorimotor, preoperational, concrete operational, and formal operational.

This article discusses Piaget’s stages of cognitive development, including important concepts and principles.

History of Cognitive Development

During the 1920s, the psychologist Jean Piaget was given the task of translating English intelligence tests into French. During this process, he observed that children think differently than adults do and have a different view of the world. He began to study children from birth through the teenage years—observing children who were too young to talk, and interviewing older children while he also observed their development.

Piaget published his theory of cognitive development in 1936. This theory is based on the idea that a child’s intelligence changes throughout childhood and cognitive skills—including memory, attention, thinking, problem-solving, logical reasoning, reading, listening, and more—are learned as a child grows and interacts with their environment.

Stages of Cognitive Development

Piaget’s theory suggests that cognitive development occurs in four stages as a child ages. These stages are always completed in order, but last longer for some children than others. Each stage builds on the skills learned in the previous stage.

The four stages of cognitive development include:

• Sensorimotor
• Preoperational
• Concrete operational
• Formal operational

Sensorimotor Stage

The sensorimotor stage begins at birth and lasts until 18 to 24 months of age. During the sensorimotor stage, children are physically exploring their environment and absorbing information through their senses of smell, sight, touch, taste, and sound.

The most important skill gained in the sensorimotor stage is object permanence, which means that the child knows that an object still exists even when they can't see it anymore. For example, if a toy is covered up by a blanket, the child will know the toy is still there and will look for it. Without this skill, the child thinks that the toy has simply disappeared.

Language skills also begin to develop during the sensorimotor stage.

Preoperational Stage

The preoperational stage of Piaget's theory of cognitive development occurs between ages 2 and 7 years. Early on in this stage, children learn the skill of symbolic representation. This means that an object or word can stand for something else. For example, a child might play "house" with a cardboard box.

At this stage, children assume that other people see the world and experience emotions the same way they do, and their main focus is on themselves. This is called egocentrism.

Centrism is another characteristic of the preoperational stage. This means that a child is only able to focus on one aspect of a problem or situation. For example, a child might become upset that a friend has more pieces of candy than they do, even if their pieces are bigger.

During this stage, children will often play next to each other—called parallel play—but not with each other. They also believe that inanimate objects, such as toys, have human lives and feelings.

Concrete Operational Stage

The concrete operational stage occurs between the ages of 7 and 11 years. During this stage, a child develops the ability to think logically and problem-solve but can only apply these skills to objects they can physically see—things that are "concrete."

Six main concrete operations develop in this stage. These include:

• Conservation: This skill means that a child understands that the amount of something or the number of a particular object stays the same, even when it looks different. For example, a cup of milk in a tall glass looks different than the same amount of milk in a short glass—but the amount did not change.
• Classification: This skill is the ability to sort items by specific classes, such as color, shape, or size.
• Seriation: This skill involves arranging objects in a series, or a logical order. For example, the child could arrange blocks in order from smallest to largest.
• Reversibility: This skill is the understanding that a process can be reversed. For example, a balloon can be blown up with air and then deflated back to the way it started.
• Decentering: This skill allows a child to focus on more than one aspect of a problem or situation at the same time. For example, two candy bars might look the same on the outside, but the child knows that they have different flavors on the inside.
• Transitivity: This skill provides an understanding of how things relate to each other. For example, if John is older than Susan, and Susan is older than Joey, then John is older than Joey.

Formal Operational Stage

The last stage in Piaget's theory of cognitive development occurs during the teenage years into adulthood. During this stage, a person learns abstract thinking and hypothetical problem-solving skills.

Deductive reasoning—or the ability to make a conclusion based on information gained from a person's environment—is also learned in this stage. This means, for example, that a person can identify the differences between dogs of various breeds, instead of putting them all in a general category of "dogs."

Summary

Piaget's theory of cognitive development is based on the belief that a child gains thinking skills in four stages: sensorimotor, preoperational, concrete operational, and formal operational. These stages roughly correspond to specific ages, from birth to adulthood. Children progress through these stages at different paces, but according to Piaget, they are always completed in order.