How Babies Listen From the Womb, According to a new Study

Not only can babies hear in utero, it turns out they start developing language sensitivity while in the womb according to a University of Kansas study.

Huddled in their mother’s womb, babies already get to have a taste of the world they’re about to born into.

Advances in ultrasonography enable the close observation of prenatal behavior.

These techniques give doctors access to valuable data on how the baby’s senses develop and how they react to external stimuli such as noise, the mother’s diet, touch, and even light.

Babies Listen From the Womb in Their own way

The hearing is the acutest sense of the fetus enabling it to start perceiving sounds before even the auditory cortex is fully developed.

Around the gestational age of 16 weeks, the fetal sense of hearing begins.

In its mother’s womb, the baby bathes in a “noisy” environment, where it constantly perceives the sounds coming from the mother’s digestive, circulatory and cardiac systems.

The baby is able to perceive sounds (the mother’s stomach gurgling, her breathing, and her heart beats) as vibrations that travel through the amniotic fluid and reaches the fetus, tickling its lips and fingertips.

At this stage of pregnancy, the fetus’ brain is not yet mature enough to interpret and understand these sensations.

However, starting from week 23, the fetus will hear ‘sounds’ to which it reacts by movement, accelerated heart rate or turning its head. High-pitched sounds, like a barking dog or a horn, will get the baby’s attention more than, say, soft background music.

The Linguistic Development Starts in Utero

It’s already established that newborns get familiarized with their parents’ native language and react differently to foreign languages. But before they step out of the womb, they form “sound memories” which last until after they’re born.

Now, a research team from the Department of Linguistics at The University of Kansas has conducted a prenatal learning study suggesting that the fetus can distinguish between different languages.

The team used magnetocardiography at the University of Kansas Medical Center, on one of two devices in the U.S. dedicated as fetal biomagnetometers.

Bio magnetometry is a noninvasive sensing technique and is more sensitive than ultrasound in detecting heart rate changes.

24 pregnant women, with a mean gestational age of eight months (35.5 weeks), were tested using the MCG (magnetocardiogram) while a bilingual speaker read two passages in English and Japanese.

The findings of the KU researchers, reported in a paper published in NeuroReport, point to the fetus’s capability for language discrimination. As a result, the fetus shows an inclination to the language they would acquire after birth–the one they’re used to hear during gestation.

Still, the baby reacts to the mother’s voice more than anything else.

Previous studies have shown that the fetus’ heart rate increases when it hears the mother’s speaking. Unlike other voices and sounds that travel through the air, the mother’s voice reverberates through her bones and internal tissues that act as amplifiers.

So, speak, sing, and let your baby get used to your language and voice while you both have that intimate, physical bond.

What sort of technical learning advancements could come from the results of a study like this one?