Editing Cognitive development (section)

=== Stages ===

==== Sensorimotor stage ====
Piaget believed that infants entered a sensorimotor stage which lasts from birth until age 2. In this stage, individuals use their senses to investigate and interact with their environment. Through this they develop coordination between the sensory input and motor responses. Piaget also theorized that this stage ended with the acquisition of [[object permanence]] and the emergence of symbolic thought.

This view collapsed in the 1980s when research was put out showing that infants as young as five months are able to represent out-of-sight objects, as well their properties, such as number and rigidity.

==== Preoperational stage ====
Piaget believed that children entered a preoperational stage from roughly age 2 until age 7. This stage involves the development of symbolic thought (which manifests in children’s increased ability to ‘play pretend’). This stage involves language acquisition, but also the inability to understand complex logic or to manipulate information.<ref>"Piaget's Preoperational Stage of Cognitive Development | Lifespan Development". courses.lumenlearning.com. Retrieved 2023-10-31.</ref>

Subsequent work suggesting that preschoolers were indeed capable of taking others' perspectives into account and reasoning about abstract relationships, including causal relationships marked the demise of this aspect of stage theory as well.<ref>Spelke, E. S. (2022). What Babies Know: Core Knowledge and Composition Volume 1 (Vol. 1). Oxford University Press.</ref>

==== Concrete operational stage ====
Piaget believed that the concrete operational stage spanned roughly from age 6 through age 12. This stage is marked by the development and achievement of skills such as [[Conservation (psychology)|conservation]], classification, serialism, and spatial reasoning.

Work suggesting that much younger children reason about abstract ideas including [[Categorization|kinds]], [[Logical connective|logical operators]], and causal relationships rendered this aspect of stage theory obsolete.

==== Formal operational stage ====
Piaget believed that the formal operational stage spans roughly from age 12 through adulthood, and is marked by the ability to apply mental operations to abstract ideas.<ref name="ReferenceB">McShane, John. "Cognitive Development: an information processing approach". 1991</ref>