Cognitive growth and development

Cognition comprises the processes by which an individual obtains knowledge of an object or of its environment. It includes: perception, discovery, recognition, imagining, judging, memorizing, learning, thinking, and frequently speech. These processes develop through a series of stages from birth onwards giving rise to a progressive increase in the ability to construct and express fundamental physical concepts (such as objects and space) and logical concepts (such as coherence and classification). Mental growth may therefore be defined as the progressive expansion of an individual's ability to deal effectively with encountered environmental situations. As such it is to be clearly distinguished from brain growth and neurological maturation, although a close relationship exists between them.

In the course of development from stage to stage, the child's interactions increasingly shift from (a) motions made in response to environmental stimulation to (b) actions upon and thoughts about the environment and himself as an object in the environment to (c) thoughts about his own thoughts and about possibilities as well as actualities. Ten such stages have been identified and may be classified as sensorimotor and symbolic operation (occasionally split into concrete operations and formal operations):< [Sensorimotor stages]

(0 to 15 months) These correspond to the stages of sensorimotor development described separately. They comprise stages of: radical egocentrism, anticipating and generalizing, static coordinating, mobile coordinating and signalling, experimenting, and symbolizing.

[Symbolic operational stages]

These comprise the stages of: preconceptual gestural verbal acts (1.5 to 4 years), intuitive quasi-verbal acts (4 to 7 years), concrete verbal acts (7 to 10 years), formal operations (10 to 15 years).