Infancy is the period from the moment of delivery when the umbilical cord is tied to the age of one year, and can be subdivided into neonatal period and infancy; from the age of one year to the age of three years is the early childhood period.
I. Neonatal period: the period from the delivery of the fetus to 28 days after the ligation of the umbilical cord. This period has very obvious special characteristics in terms of growth and development and diseases, and has a high morbidity and mortality rate, so this special period in infancy is separately classified as the neonatal period.
Second, the infant period: from birth to 1 week of age is the infant period. This period is a period of extremely rapid growth and development, so the demand for nutrition is relatively high. At this time, although the growth and development of various systems and organs continue, but not mature and perfect, especially the digestive system is often difficult to adapt to the digestion and absorption of a large amount of food, prone to nutritional and digestive disorders.
Changes in infancy are enormous, as human characteristics of upright walking, two-handed movements, the ability to communicate verbally, after gradual development, began to appear at this stage, the senses (audio-visual, taste and skin temperature and touch) also have a relatively rapid development, perception began to appear, began to have a more obvious attention and initial memory capacity.
1.Movement development pattern
(1) from the overall action to the differentiated action, such as from the purposeless movement of the hands to the purposeful movement of one hand.
(2) From the upper action to the lower action, in order to raise the head, turn over, sit, crawl, stand and even walk. (From proximal to distal)
(3) From large muscle movements to small muscle movements, such as from head and trunk movements to dexterous small muscle movements of the hands. (Gross to fine)
(4) From positive to negative movements, such as holding first and then releasing, walking forward and then walking backward.
The development of hand movements is huge, and the development of hand movements promotes the increasing improvement of brain structure and function, which is more conducive to the improvement of children’s intellectual level.
2.Speech development goes through stages
(1) Articulation stage (1 to 3 months).
(2) Teething stage (4~9 months).
(3) Comprehension of speech stage (7, 8 to 11, 12 months).
(4) Beginning of speech stage (9 to 12 months).
3. Rapid sensory development
Infants’ vision changes significantly with age. Head-eye coordination begins to appear at 1 month, and the eyes can shift with objects within 90° of their horizontal position; at 3 months, they have better coordination and begin to distinguish the size and shape of objects; at 9 months, they can look at the activities of people within 3 to 3.5m for a longer period of time.
Perception is an intellectual activity formed on the basis of sensation, which is closely related to sensation, and infants’ perception appears very early, such as about half a year old infants have learned to recognize the depth.
With the growth of age, the nervous system continues to mature, the infant’s memory ability is becoming more and more obvious, such as 1 to 4 months of age, such as the hands of the toy will be taken away from the infant will not indicate, and to 4 to 8 months of age, there is a loss of performance, and even for a very short time to find. The memory is characterized by a small amount of content, limited to a few people and events in daily contact, and a short memory period, generally lasting only a few days. Thinking is an indirect and generalized reflection of objective reality by the human brain, and the thinking activity in infancy can only be described as a kind of germination.
4. Rapid physical growth
The year after birth is the most rapid period of physical growth in a person’s life, and both height and weight will experience the first peak of growth.
Third, early childhood: 1 to 3 years old children’s physical development is slightly slower than before, 1 to 2 years of age, the annual growth in length of about 10 to 12cm, 2 to 3 years of age, the annual growth in length of about 7 to 8cm. children’s weight increased by an average of about 2kg per year, 1 to 3 years old children’s body shape is still longer trunk, lower limbs relatively short. Due to the increase in activity, it is normal that they are not as fat as in infancy from the outside. At the age of 2, they can speak multi-word language, walk, jump and run, and have more and more contact with the outside environment and things, and their language, thinking and social skills are developing faster and faster.