The Brain During Childhood
Cognitive development refers to the development of a child in terms of information processing, conceptual resources, perceptual skill, and language learning. The brain grows and matures rapidly during early childhood, faster than any other organ in a child's body. Once nerve cells in the brain are in place, they form synapses. These synapses release neurotransmitters, which are chemical signals that help the brain communicate. Synapses evolve rapidly, and in doing so, some synapses will die off to make room for new or more important ones. If a neuron is not being used by the brain, it goes through a process known as synaptic pruning—the removal of unnecessary neurons to make room for necessary ones.
Structure of a nerve cell
Synapses, or the spaces between nerve cells, develop rapidly during childhood. These structures are responsible for releasing neurotransmitters, which are chemical signals that help the brain communicate.
Glial cells, which account for half of all brain mass in early childhood, are responsible for a process known as myelination. This process improves message transfer between synapses and assists in brain development. The connection between neighboring neurons (which is made smoother through myelination) allows for advanced brain function, such as planning and implementing behaviors and integrating sensory information from the environment. Due to synaptic pruning, myelination, and a child's environmental experiences, the developing brain will grow from 30 percent of its adult weight at birth to 70 percent by age 2.
Neuroplasticity is also an important aspect of early childhood development. Also known as brain plasticity, neuroplasticity is an umbrella term that refers to changes in neural pathways and synapses caused by changes in behavior, environment, neural processes, thinking, and emotions—as well as changes resulting from bodily injury. The concept of neuroplasticity explores how the brain changes over the course of a lifetime and how different areas of the brain can evolve and adapt over time. This change occurs on a variety of levels, ranging from cellular changes (caused by learning) to large-scale changes in response to injury. The role of neuroplasticity is considered important to healthy development, learning, memory, and recovery from brain damage.
Cognitive Development and Piaget's Stages
The Swiss cognitive theorist Jean Piaget was one of the most influential researchers in the field of child development. He developed his four-stage theory of cognitive development based on the idea that children actively construct knowledge as they explore and manipulate the world around them. Two of these stages, the preoperational and concrete operational, are especially important in early childhood development. According to Piaget, each stage of development incorporates previous knowledge; that is, a child needs to go through an earlier stage in order to fully develop in a later stage.
Preoperational development allows children to increase their mental representation of objects, generally through make-believe play. Piaget states that language is the most flexible means of mental representation; at the same time, young children do not yet have the capability to use language alone as a means of representation. Rather, children perform actions as a means to master language and symbolic thought. Sociodramatic play, in which children play with others and create elaborate plots and characters, culminates in the understanding of representational thought and activity. Much thought during the preoperational phase is egocentric—focused only on the child's point of view.
Concrete Operational Development
During the concrete operational stage, a major turning point in cognition occurs: the appearance of more logical and organized thought. Several key thinking processes emerge during this stage, including reversibility, seriation, and transitive inference. Reversibility is the capacity to go through a series of steps and mentally reverse them, ending up at the beginning. Seriation is the ability to order items by a quantitative dimension, such as height or weight. Transitive inference is a relational concept in which children can understand how objects are related to one another; for example, if a dog is a mammal, and a boxer is a dog, then a boxer must also be a mammal.