We started today with working on identifying Ling sounds. Today, T was able to pick out the toys paired with “mmm,” “ooo,” and “ahh”! When the speech therapist said “can you show me mmmm?”, T was able to point to the corresponding ice cream toy out of 4 or 5 toys in a bin (and did similarly for the “oooo” ghost toy and the “ahhhh” airplane toy). I was so surprised he remembered these pairings, since we don’t have these toys at home and so aren’t able to practice this at home. I think it’s possible he identified them by chance, but I do think he’s getting the hang of this each time we try!
One really interesting thing we learned about today from T’s speech therapist was about “prosodic bootstrapping.” (Note: I am not a speech therapist, and really don’t know much about linguistics, so the explanation below is just to the best of my understanding!)
Prosody relates to the larger parts of speech than vowels and consonants, like syllables, words and phrases. Prosody gives us information about speech like the speaker’s mood, whether a sentence is a question or a statement, whether a sentence is said sarcastically, etc. Prosody also helps indicate a language’s underlying grammar. For example, prosody can indicate clause boundaries within a phrase or sentence. Consider the sentence “he walked the dog.” – In English, it would be unlikely to insert a pause between “the” and “dog,” because that splits the phrase “the dog.” The locations and durations of pauses within phrases are one example of prosodic information. Other auditory cues used to convey prosody include: loudness or stress (e.g., which parts of a word or clause we emphasize), frequency or pitch of the voice and how it changes (e.g., in English, pitch tends to rise as we ask a question), and duration and timing of pauses (e.g., to mark clause boundaries, as mentioned above).
Bootstrapping refers to way in which infants naturally acquire their native language, just by hearing it around them and spoken to them. In particular, bootstrapping refers to the idea that infants use innate statistical learning abilities to learn small bits of information about language and build on these small bits to build up their understanding of their native language. A particular example of this is how infants use statistical learning to identify word boundaries (see ) – in English, the letter combination “st” is fairly common (as in “sting”), but the combination “gb” is not. Just by hearing streams of speech, infants learn that “st” is common, but “gb” is not, and this knowledge helps them segment words within a stream of speech. Take the example of the stream of speech “stingingbee” – this can be broken into the words “stinging” and “bee,” and “gbee” not likely to be a word, because in English, “gb” is not a common combination.
So, “prosodic bootstrapping” is how infants learn to use the auditory cues that indicate prosody to learn about the intent of speech (is it a question? said angrily or sarcastically?) or the underlying grammar (which are the clauses that are grouped together). One really cool thing is that newborn infants cry with a prosody that is similar to their native language (see ), which may indicate that they are learning prosody of their native language heard in the womb! I hope to learn more about how infants (particularly those with hearing loss) learn to use prosody information, and will hopefully write more about this as I learn more.
So, to get back to T and our speech therapy session – T’s speech therapist asked if we had noticed him babbling with different prosody – for example, “ba da ga ba?” or babbling with excitement versus irritation. We have definitely noticed that when he’s ready to get up for the day in the morning (or, at 2 am in his case!), he will start off babbling happily, and then his voice gets more and more insistent and agitated until we finally get him up. Also, he seems more likely to respond vocally to us when we ask him a question (with a rising tone at the end of the question) than when we make a statement and then pause, which indicates that he is picking up on the auditory cues that indicate questions versus statements. We will definitely be paying more attention to this now that we talked about this today!
 Saffran, Jenny (1996). “Word Segmentation: The Role of Distributional Cues”. Journal of Memory and Language 35 (4): 606–621.
 Cross, Ian (2009). “Communicative Development: Neonate Crying Reflects Patterns of Native-Language Speech”. Current Biology19: R1078–R1079.