I. Definition of perception (a) Sensation Sensation is the individual properties of the stimulus that are reflected by the information processing of the nervous system as a result of the stimulus acting on the sensory organs. We see colors, hear sounds, and taste are our senses. It can be thought of as the stimulus passing through the receptors or receptor system to cause the individual to produce basic experiences inside and outside the body, and the perception and description of these experiences is sensation. Sensation itself is a fairly immediate and timely basic experience that is the basis for all higher mental phenomena. It acts as a basic bridge between the individual and the environment and is the first step in our understanding of the world. (B) Perception Perception is the reflection in the brain of the whole of what acts directly on the sense organs, and is the process of organizing and interpreting sensory information. Perception is the active behavior of the organism in order to know the world, and the process of perception is the process of constantly differentiating effective stimuli from the environment. For example, in the process of building blocks, children can find differences in the size, color, appearance, and texture of the same block, and they can also perceive changes in the size and shape of the block at different locations, but it is still the same block. When the block changes in different positions, different temporal and spatial events must occur. Through the process of manipulation, children will obtain more and more information, events, and spatio-temporal sequences of the environment from objects. Second, the key period of various sensory development Taste: at birth, the sense of taste is well developed, and can produce different responses to different flavors such as sweet and sour; from 4 to 5 months to the slightest change in food is very sensitive to the key moment of taste development, this period should add all kinds of complementary foods at the right time, so that they get used to different flavors of food. Sense of smell: at birth, the olfactory center and nerve endings are already developed, and when they smell milk, they will look for the nipple; from March to April, they can distinguish pleasant and unpleasant smells; from July to August, they start to respond to aromatic smells. Vision: Newborns are sensitive to differences in brightness and develop discriminatory power rapidly. However, in the first 2 to 3 weeks of life, both eye movements are still uncoordinated. Visual concentration, which becomes apparent only at 2 months of age. By 4 months of age, visual regulation is very effective, and the duration and distance of gaze are extended, and visual focus gradually changes from passive to active. Children’s visual perception (i.e., the ability to accurately discriminate between subtle objects or objects at a distance) begins to develop during the preschool years. However, the rate of development is uneven: i.e., it develops faster in the middle preschool period than in the late preschool period. Visual perception can also be improved through interesting play activities or word regulation. Early school-age children’s visual perception develops with age and learning activities, and can even surpass that of adults around age 15. Hearing: There has been disagreement about when newborns first hear sounds, with some studies suggesting that hearing occurs within 5 days to 24 hours or even minutes after birth. Other studies suggest that it is several months later. It is now generally accepted that newborns are able to respond to certain sounds, but significant auditory focus is not clearly evident until 3 months of age, when they are able to perceive sounds from different directions and turn their heads toward the source. 3-4 month old infants are able to show pleasure to music, express uneasiness to strong sounds, and differentiate between adult (especially maternal) sounds. Development of skin sensations: Skin sensations include touch, pain, temperature and depth sensations. Tactile sensation: is the basis for certain reflexes, the newborn’s eyes, mouth, palms, soles and other parts of the touch has been very sensitive, touch that there is a response, such as transient eyes, open mouth, retracted hands and feet, etc., while the forearms, thighs, trunk is more sluggish. Nociception: newborns have pain sensation, but it is sluggish; it gradually improves from the second month. Temperature perception: Temperature perception is very sensitive at birth, especially in response to cold, such as crying when leaving the maternal environment or when the temperature drops suddenly; at 3 months of age, they can distinguish the difference between water temperature of 31.5℃ and 33℃; at 2 to 3 years of age, they can distinguish the properties of soft, hard, cold and hot objects through contact; at 5 years of age, they can distinguish objects of the same volume and different weight. Spatial and temporal perception: Spatial perception includes the discrimination of distance (or depth), shape, size, and so on. The formation of spatial perception depends first on the child’s ability to form a variety of spaces from life experiences and also on the acquisition of words that represent spatial relationships. The general trend of children’s orientation perception development is: at the age of 3, they can only identify up and down; at the age of 4, they start to identify front and back; at the age of 5, they can start to identify left and right with themselves as the center; at the age of 6, they can only reach the level of fully and correctly identifying four orientations: up, down, front and back. Time perception: Time perception is the reflection of the continuity, sequence, and speed of objective phenomena. At the end of infancy, children begin to have the germ of time perception. Because time relationships are abstract and not as much of a pillar as spatial perception, preschoolers have a low level of time perception development. Third, the scientific promotion of infant perceptual development parents can be based on the laws of infant perceptual development, planned training for children, such as the use of brightly colored, audible toys to tease the little baby to promote the development of their vision, hearing. After the full moon, infants should often be carried outdoors to play and use methods such as listening to music, watching pictures and playing with toys to promote their visual and auditory development. On the basis of sensory development, combined activities such as visual, auditory, tactile and touching are used for perceptual training, so that children gradually perceive various characteristics of things, such as light, darkness, hot and cold, color, shape, size, length, thickness, weight, etc., and also perceive time concepts such as morning, evening, today and tomorrow. According to the law of infant perceptual development, grasp the key period of infant perceptual development, through scientific methods, can effectively promote infant perceptual development.