1. Neonatal period: ① Difficulty in breastfeeding; ② Excessive quietness, small cry or continuous shrill cry; ③ Less spontaneous movement, general flabbiness and weakness; ④ General stiffness, good jerking, increased muscle tone, often scurrying out of the swaddling clothes, head dorsiflexion, sometimes head to the side, both lower limbs tonic extension; ⑤ Easily startled, convulsions, screaming or restlessness; ⑥ Abnormal posture, such as upper limbs inward, internal rotation, hand fist, etc. 2.1-3 months: ① thumb inward, hand clenched fist or upper limb inward, inward rotation; ② inattentive to look at people, eyes do not follow what is in front of the eyes; vertical head instability, neck can not be vertical, head shaking from side to side or head to one side, prone position can not lift the head; ③ muscle tone changes, such as general stiffness, trunk hard extension or general tenderness. 3. 4-5 months: ① eyes do not follow what is in front of them, do not pay attention to people, eyes are not flexible; ② expression is dull and inflexible, no response when teasing; ③ can not roll over, head lift in prone position is less than 90°; ④ body gradually becomes stiff, there is a mild antalgic posture or lower limbs crossed in scissor-like; ⑤ body posture is asymmetrical, etc.