Fetuses are attracted to face-like images before they have encountered any real-life face, according to a groundbreaking study. The research found that they turn their heads towards such images more than other shapes while still in the womb.
The study, published in the journal Current Biology, projected light in the form of red dots through the uterine walls of 39 women who were 34 weeks pregnant.
The three dots were presented in both upright and inverted positions. The upright positions resembled face-like stimuli with the dots acting as two eyes and a mouth.
The scientists observed the fetuses' responses to the light by using a 4D ultrasound, and found that they turned their heads more often to look at the face-like stimuli.
“In our study they had to move their head to keep looking at the face-like stimulus when we moved it away from them. So they are active participants in finding information from the environment," said Vincent Reid, a psychologist at Lancaster University in the United Kingdom, as quoted by The Telegraph.
He went on to note that the way the fetuses responded to the face-like dots was very similar to the way infants do.
"We know from babies that they prefer to look at faces more than any other stimulus," Reid said.
According to Reid, the findings likely suggest that the "bias to look at faces" is due to the way light falls in the womb.
"I believe that it is likely this bias to look at faces is triggered by exposure to patterned light in the womb and is due to prenatal visual experiences," he said.
"It is possible that the maternal rib cage could introduce variation in light penetrating the womb and this may be enough visual information to create this bias."
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The study is seen as extremely significant, as it is the first to show that it is possible to explore the visual perception and cognition in babies before they leave the womb.
"We have shown the fetus can distinguish between different shapes, preferring to track face-like over non-face-like shapes," Reid said, as quoted by Phys.org.
"This preference has been recognized in babies for many decades, but until now exploring fetal vision has not been attempted," Reid added.
The researchers are now working on a way to improve the light source used in the current study, in preparation for additional exploration of fetal perception and cognition in the womb – particularly determining whether a fetus in the third trimester can also discriminate numbers and quantities, the way newborns can.