The first memories you ever made were made when you were just a preborn baby in your mother’s womb. At least that’s what researchers from a variety of studies are concluding. At what point they are first capable of making memories is still up for debate, but with each study, the proof was found that these little humans are capable of creating memories.
A 2009 study published by Child Development looked at short-term memory in preborn children ages 30-38 weeks gestation. Nearly 100 pregnant women participated in the study, which tested how their preborn children responded to specific vibroacoustic stimulation – a low sound that makes a vibration. The reactions were observed by performing an ultrasound. Researchers found that the first time the fetuses received the stimulation, they were startled. However, after repeated exposure to the stimulus – about 13 times, each thirty seconds apart – the fetuses stopped reacting. This showed that they got used to the sound. Researchers call this habituation, which is something we all do. For example, we get used to the sounds around us such as the hum of a heater or air conditioner to the point that we don’t even notice it anymore.
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“Habituation is a form of learning and a form of memory,” explained Dr. Jan Nijhuis, a co-author of the study and an obstetrician.” He and his colleagues found that 30-week-old fetuses had a memory of 10 minutes and with each round of stimulation they were able to become habituated to the sound faster. They also discovered that at 34 weeks, preborn children were able to “store information and retrieve it four weeks later.”
“So that shows that there is a sort of remembrance of 4 weeks,” he said.
A separate study by researchers at the University of Helsinki asked a group of pregnant women to play a track of the nonsense word “tatata” to their preborn child every so often. Another group of pregnant women acted as the control group and did not play the track at all. After the babies were born, the researchers watched their brain activity while playing the track of “tatata” and found that those who had heard the sound while in the womb registered brain activity when they heard it after birth, while those who were not exposed to the sound in the womb did not register brain activity when they heard it after birth. Researchers concluded that a fetus’s memories last beyond birth.
In a more recent study, published in 2013, researchers used “cardiac orienting response” – a small change in heart rate – to learn when a fetus is capable of memory. Pregnant women were asked to read a nursery rhyme that they had never read to their preborn children before. Twice a day between 28 and 34 weeks gestation the mothers read the rhyme. Testing was performed at 28, 32, 33, 34 weeks to learn whether or not the preborn child recognized the nursery rhyme. Then, the mothers stopped reading the nursery rhyme at 34 weeks and researchers performed the testing again at 36 and 38 weeks. They found that by 34 weeks, the fetuses’ heart rates slowed when they heard the rhyme, showing that they responded to it. In a control group who had not been reading the nursery rhyme, the babies’ heart rates accelerated when they heard it for the first time.
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Each of these studies indicates that preborn children are capable of forming memories. The information researchers have learned can help doctors to better care for both preborn children and newborns, especially those who are premature. But this research also shows the humanity of the preborn child. Not only are they physically capable of hearing, but they are also capable of having an emotional connection with the sounds they hear, including the voices of those around them. Fetuses — preborn children — are human beings who should have the same rights as the rest of us.