It appears that premature babies benefit greatly when they hear their mother’s voice, especially while still in the hospital.

Researchers have shown that preemies in the neonatal intensive care unit may experience more cognitive development the more their mothers interact with them. That’s compared with infants who only hear the everyday noises of an ICU.

These findings were published recently in the Proceedings of the National Academy of Sciences.

Premature babies often experience developmental problems tied to hearing and language. So the researchers sought to find out how they’re affected by the time spent in an incubator instead of inside their mother’s womb.

The research team chose a group of preemies born at 25 to 32 weeks gestation. About half of the babies were assigned to hear the normal noises of the hospital, while the other half heard the recorded heartbeat and voices of their respective mothers. They listened to those recordings three hours a day for a month.

The researchers then used ultrasound scans to assess the babies’ brains. The infants who heard the recordings had larger auditory cortexes. The auditory cortex is the brain’s sound center.

Despite these findings, the study notes that a recording is no substitute for a mother’s actual voice. Also, it’s unknown how much the voices of other people in the hospital might have affected the babies.

Incubators are great tools that help save many young lives in the neonatal intensive care unit. Parents of premature babies sometimes have to wait to hold their babies, but one thing they can do to help when they visit the NICU is to talk and sing to their teeny-tiny ones. It may seem like a small effort to make, but the benefits could be immeasurable.