What is the visual perception of the fetus?

Fetal vision develops slower than other senses. The reason is obvious, that is, although the uterus is not dark, it is not suitable for eyes to see. However, the eyes of the fetus are not completely blind. From the fourth month, the fetus is very sensitive to light. When the mother basks in the sun, the fetus can feel it through the change of light intensity.

The light shines directly on the mother's abdomen, which sometimes makes the fetus feel small and fast. At this time. Even if the fetus doesn't turn its back, it will look frightened. Modern medicine uses B-ultrasound to observe that when the flashlight shines on the abdomen of pregnant women, the fetal heart rate will change dramatically.

Newborn babies are not particularly sensitive to vision. And its vision is narrow, but if you put something in front of the newborn, the newborn can see clearly. Moreover, the newborn can clearly see the change of mother's expression at the distance of 15 ~ 30 cm. There are even reports that newborns can clearly see the outline of their fingers at a distance of about 3 meters.

Dr. Albert Riley expounded this point brilliantly from a theoretical point of view, according to the doctor. The visual defects of newborns, at least in part, are still traces of fetal living habits. If the newborn only cares about the matter within 30-40 cm, it is because this distance is equal to the length he just left the uterus. A few years ago, Professor Kobayashi of Japan used strong light to illuminate the abdomen of pregnant women and found that the fetus closed its eyes. In the past two years, it has been found that when the photographic light is suddenly turned on and emits strong light, the fetus moves immediately after the strong light enters the uterus through the abdominal wall of a lying pregnant woman, and it takes several minutes to adapt before the fetal movement weakens. In the obstetric experiment of Beijing Tiantan Hospital, in order to avoid the fetal reaction caused by the thermal effect of strong light stimulating the abdomen of pregnant women, incandescent bulbs were soaked in a glass water tank filled with water. The light shines on the abdominal wall of pregnant women through the glass filled with water, and then penetrates into the uterus. It is also found that sudden exposure to light will lead to accelerated fetal movement.

In 198 1, Dr. Jasonc Dimholz of Harvard Medical School found that the newly developed instrument can be used to visually observe the development of fetal eyes in the second half of pregnancy and identify ways to distinguish eye movements. More than 90% of fetal eyes can be seen by naked eyes at 16-42 weeks. Eye movement is slow in 16 weeks, rapid eye movement begins in 23 weeks, and appears more frequently in 24-35 weeks of pregnancy. After 36 weeks, it is common that the eyes are inactive, showing a "deep sleep" state.