It’s critical to realize a few things:
(1) The infants shown here don’t actually *understand* what they’re hearing; they’re just noticing novel sounds. Many CI recipients do eventually learn to comprehend and produce speech; many do not. (2) Nikki, the 1st person shown here, lost her hearing at age 18. I don’t know about Elena, but I would guess that the same is true, or that hear hearing loss was not profound. We cannot generalize from the outcomes of these cases to prelingually deaf infants. (3) The toddlers shown here all had substantial English proficiency pre-implant. Whether that comes from only mild/moderate hearing loss, or impressive speech therapy, the important part is that their little brains have already acquired the linguistic system that the CI is going to help them perceive. Again, it’s unwise to generalize from these cases to prelingually deaf infants who do not have any command of English. (4) There is a common belief that learning sign language will delay the development of speech through a CI. However, a major study published in April 2010 in the Journal of the American Medical Association documents that implanted children who sign fare no worse than implanted children who don’t sign. (5) Taken together, 3 & 4 suggest that the best course of action for deaf infants may be exposing them first to a natural sign language so that they already have a linguistic system in place if/when they receive a cochlear implant. That way, their cognitive development will not lag behind at any stage, and they will have a language that they can use to ask questions with as they’re learning English.