Developmental Milestones: Physical and Motor Growth (0-6 Years)
General Characteristics of Children Aged Zero to Six Years
This section details the characteristics of children aged zero to six years, focusing on their physical appearance, motor skills, affective development, psychological growth, and social interactions.
1.1. Physical Growth and Development
Physical growth is a highly organized, steady, and continuous process. It does not occur through sudden arrests and jumps, but rather follows a specific sequence and a maturational calendar. Physical growth also follows a particular pathway, controlled by internal mechanisms that guide the body from initial immaturity toward increasing levels of maturity.
Human growth includes control and correction mechanisms. If a problem or disorder causes growth to deviate from its planned trajectory, the body tends to regain lost ground once the problem or condition ends. This is known as the recovery process (or catch-up growth).
A deviation from the growth trajectory can be natural or due to external problems, such as malnutrition. As a general principle, the earlier, more severe, and longer the factor that separates the child from their growth curve, the more difficult it is for recovery processes to be fully realized. This is because growth occurs most rapidly in utero and during the first two years of life.
We can conclude that growth is not only controlled by endogenous (internal) mechanisms, but is also conditioned by external factors.
[Note: Data illustrating physical growth during the first two years of life, typically presented in a table, shows characteristics of children within the average range. Any deviation must be analyzed taking into account various factors.]
The growth rate, which is very intense during the first two years of life, decreases gradually and tends to stabilize in the period between three and six years. The child’s physical development during this time is characterized by a variation of body dimensions. Significant changes occur in the skeleton and musculature, which directly affect the development of psychomotor and physical capacity. The skeleton undergoes an accelerated calcification process, resulting in strong bones after two years of age.
1.2. Motor Characteristics and Skill Acquisition
The achievements children make in terms of motor development during this period are truly important. The key acquisitions that take place are:
Diffuse Motor Activity (First Months): Initially, there is widespread, diffuse motor activity corresponding to the first months of existence. This activity is under the direction of subcortical centers. The child moves without their movements responding to intentional behavior or having a concrete goal.
Coordinated Motor Activity (Around Four Months): Coordinated motor activity begins through the intervention of the cerebral cortex, which exerts a directive and inhibitory influence. Movements like the opening and closing of hands are no longer mechanical and automatic; they become an attempt at instrumental use, although their effectiveness for grasping objects is still limited.
Increased Cortex Participation (End of First Year): Toward the end of the first year, cortex activity increases, allowing for the coordination necessary for handling and movement activities. The child becomes capable of crawling, sometimes walking, grasping objects, and placing and removing them from certain containers.
Full Perceptual-Motor Usability (Around Two Years): Around two years of age, cortical activity reaches significant levels of functioning, and the child already has full usability of their perceptual-motor mechanisms. The accuracy, ease, efficiency, and flexibility with which they use these mechanisms depend heavily on environmental influence and the opportunities provided by their surroundings to move about and manipulate objects.
In the third year of life, the child walks safely, can speed up or slow down, change direction, and stop at will. They are also able to go up and down stairs.