We frequently use baby talk in our best efforts to communicate with newborns, smothering them with strings of "goo goo" and "ga ga" until they smile or cry in return. But oversimplifying our language may not be necessary — scientists from Paris recently a group of newborns and found that their speech perception skills were more astute than previously thought.
To perceive speech, our auditory system must be developed enough to differentiate the spectral (frequency-based features for pitch, rhythm) and temporal information (time-based features to interpret) that make up our speech. Studying how our brain processes information might help us deduce whether or not the foundations of language learning and speech comprehension are present from birth. If infants interpret these cues differently than adults do, they may also be absorbing different linguistic information, like envelope cues that aid in consonant identification.
The basilar membrane in the inner ear receives speech by the temporal modulations of the speech signal into different frequency bands. The researchers found that six-month-olds were able to differentiate consonants similarly to adults. Once this was established, they looked at how newborns interpreted different types of consonants. To discriminate plosive consonants (produced by stopping airflow using the lips/teeth and then a sudden release of air, such as in "t," "k," and "p" sounds), newborns required fast cues, as opposed to adults and six-month-olds, for whom slow cues were sufficient.
This study showed the physically immature newborn brain is capable of processing the acoustic components of speech, which is the foundation of language learning. As opposed to adults, who can rely only on slow cues, newborns need fast envelope cues to perceive consonants. The specialization to different temporal cues reflects infants’ great speech perception skills despite limited language experience and an immature auditory system.