Baby’s low intelligence has the following characteristics: 1, the baby’s development level lags behind that of children of the same age, for example, in the newborn period showed difficulties in eating milk, will not suck, or three months old children will not look at people’s faces, do not like to look at people’s faces, and do not chase things, do not chase the sound, four months old children do not want to reach out and grab things, six months old children will not sit, can not understand their own names, and do not recognize the living These are all signs of low intelligence; 2, late speech, many children at the age of two still can not call their parents, usually low intelligence baby motor skills will also lag behind, roll over, sitting, crawling, walking are later than children of the same age; 3, low intelligence may also be accompanied by abnormal facial and physical appearance, such as hydrocephalus children’s head circumference is particularly 4. Mental retardation may also be accompanied by microcephaly, a particularly small head with overlapping cranial sutures, a short stature, a peculiar facial appearance, abnormal palm lines, a particularly light color of the skin and hair, a peculiar odor, low muscle tone, a particularly floppy hold, or abnormally high muscle tone, and very stiff limbs. If a child is found to have one or more of these manifestations, it is important to visit a hospital to have the child’s intelligence evaluated by a professional physician.