Healthy Baby - Health Care and Family Rearing Guide for Children Aged 0-6

Author: Hou Mei, Zhang Liqin
Publisher:
Publish Date: 2006-10-01
Features: Modern young parents are no longer satisfied with simply making sure their children are well-fed and warmly clothed. Instead, they have a profound understanding of the importance of scientific parenting. They place great emphasis on children's health and education investments, seeking not only to know "what" but also "why." The birth and growth of a new life bring endless joy and hope to parents, but also add many "troubles" to young parents. Whether a child's development is normal, what to do if it deviates from the norm, what causes illness, and how to help children develop their potential—these are a series of questions that often parents. Many parents, due to a lack of medical and healthcare knowledge, overlook early developmental abnormalities in their children, missing the best treatment window. Others resort to indiscriminate treatments, incurring significant financial losses and delaying proper diagnosis, which can lead to lifelong regrets.
Section 2: Neurological and Motor Development
Children's bodies are in a constant stage of growth and development. As the nervous system gradually matures, reflexes, posture, and muscle tone in children exhibit characteristic patterns and regularities for each stage. Understanding neurological and motor development helps in health checks, early detection of abnormalities, and assessment of developmental issues.
I. Neurological Development
In the early stages of fetal embryonic development, the embryo is shaped like a flat disc and consists of three distinct layers of cells: the endoderm, mesoderm, and ectoderm. The endoderm eventually develops into internal organs and tissues, the mesoderm into bones and muscles, and the nervous system and skin all originate from the ectoderm. In early human embryonic development (week 3 of pregnancy), the ectoderm forms the neural plate, which then develops into the neural tube. The anterior part of the neural tube differentiates into the central nervous system, while the posterior part develops into the spinal cord.
Newborns have the same number of brain cells as adults. The gradual maturation of the nervous system after birth primarily involves myelination and the refinement of neural networks. At birth, only the spinal cord and brainstem are myelinated. As growth progresses, myelination develops from the lower to the upper regions and from the dorsal to the ventral side. By 2 months, myelination reaches the pons; by 6 months, it reaches the midbrain; and by around 1 year, myelination of the cerebral cortex begins to appear, with completion occurring around age 5. Even after adulthood, myelination can continue to improve.
Therefore, the development of the child's nervous system begins with primitive reflexes at the level of the spinal cord and pons, gradually progressing to upright reflexes at the midbrain and thalamus level, and finally to balance reflexes at the cerebral cortex level. The development of neurological reflexes in children follows a clear pattern of increase and decrease: primitive reflexes first appear, are gradually inhibited and disappear as higher-level centers develop, and are then replaced by upright and balance reflexes.
II. Reflex Development
(1) Primitive Reflexes
The central nervous system for primitive reflexes is located in the spinal cord, medulla oblongata, and pons. These reflexes are present at birth and gradually weaken and disappear as the nervous system develops. Numerous primitive reflexes are essential for the fetus to be delivered and form the foundation of early infant life. The absence, reduction, or persistence of primitive reflexes can indicate neurological disorders. Commonly used primitive reflexes include the following.
1. Moro Reflex
Method: The child lies on their back. The examiner lifts both arms, pulling the shoulders up, causing the head to bend backward but remain on the bed. Then, the examiner suddenly releases their hands.
Response: In normal infants aged 0–3 months, the Moro reflex manifests as an embrace-like movement: the arms are extended outward, the distal phalanges of the thumb and index finger are flexed, and the fingers spread out fan-like. This is followed by inward and upward flexion of the shoulders and arms, creating a continuous embracing motion. The legs are also extended, and the toes spread out. The infant may appear startled. In normal infants aged 3–6 months, the response is an abrupt outward extension of the arms, followed by a quick fall onto the bed, causing slight discomfort.
Significance: The Moro reflex helps extend the trunk and limbs, aiding in childbirth. Its absence or disappearance suggests lower central nervous system function or inhibition due to factors like birth injury or asphyxia. Asymmetry may indicate hemiplegia, brachial plexus injury, or muscle damage. Persistence beyond 6 months suggests brain damage or sensory-motor disorders. Hyperactivity is common in premature infants, low calcium levels, and kernicterus.
2. Sucking Reflex
Method: Place the nipple or a finger into the infant's mouth.
Response: The infant actively closes their mouth, suckles rhythmically,