What is developmental psychology?

Developmental psychology is the study of permanent changes that occur throughout the human lifespan. It is studied through four main divisions - the development of physical characteristics, cognitive and intellectual abilities, social capacity, and emotional expression.

Piaget's Theory of Cognitive Development

Jean Piaget believed that a child’s thinking changed with age, gradually progressing through a series of fixed stages. At each stage, they are able to reason in a qualitatively different and more advanced way than they could prior. Schemas, as a basic concept, are basic building blocks for cognitive models that enable the formation of mental representations of the world. Advancement refers to an increase in the number of schemas existing in the individual’s mind and their complexity.

Children progress their cognitive abilities through the processes of:

• assimilation - interpreting new experiences in terms of existing schemas.

• accommodation - changing schemas in response to new experiences.

Stages of Cognitive Development

Piaget proposed four sequential stages of cognitive development:

Criticism of Piaget’s Theory

Although Piaget’s theory was a landmark contribution to the field of developmental psychology, there were various weaker aspects of his theory. The theory:

• tends to underestimate younger minds

• does not distinguish between competence and performance

• neglects the impact of social and cultural influences

• is based on a task that does not provide children with familiar materials

• neglects the possibility than some children may show abilities of different stages

• confuses motor skill limitations with cognitive limitations in assessing object permanence

Vygotsky’s Criticism

Claimed that Piaget placed little emphasis on social interaction. They stressed the role of social interaction that occurs in a socio-cultural context. Instead, Piaget believed that cognitive advancement is automatic

Hughes’ Policeman Task

Designed a task that asked children to hide a doll so that a ‘policeman’ can’t see it. From this, it was proposed that Piaget’s experiment was too abstract to make real world sense. 90 percent of the children correctly hid the doll even when a second policeman was introduced. It found that 3–5-year-olds are not egocentric.

Siegal’s Language Criticism

Believed that a lack of conservation was due to the breakdown of conversational rules between adults and children. They explained that children believed they were wrong when:

• the experimenter asks questions when the answer is obvious

• the question is repeated when an answer had already been given