In a high-amplitude sucking experiment, how would a researcher know an infant can differentiate different speech sounds? The infant sucks faster on the pacifier when they hear a new sound. The infant...

Extracted text: In a high-amplitude sucking experiment, how would a researcher know an infant can differentiate different speech sounds? The infant sucks faster on the pacifier when they hear a new sound. The infant sucks slower on the pacifier when they hear a new sound. The infant turns their head when they hear a new sound. The infant sucks faster on the pacifier the more they hear the same sound.