Even before infants can comprehend word meaning,
prosodic details assist them in discovering syntactic boundaries.
Prosodic bootstrapping or
phonological bootstrapping investigates how prosodic information—which includes
stress,
rhythm,
intonation,
pitch, pausing, as well as
dialectal features—can assist a child in discovering the grammatical structure of the language that they are acquiring. In general,
prosody introduces features that reflect either attributes of the speaker or the utterance type. Speaker attributes include emotional state, as well as the presence of irony or sarcasm. Utterance-level attributes are used to mark questions, statements and commands, and they can also be used to mark contrast. • Prosodic features associated with the speaker: emotional state, irony, sarcasm • Prosodic features associate with utterance type: question, statement, command, contrast Similarly, in
sign language, prosody includes
facial expression,
mouthing, and the
rhythm, length and tension of gestures and signs. In language, words are not only categorized into
phrases,
clauses, and
sentences. Words are also organized into prosodic envelopes. The idea of a prosodic envelope is that words that go together syntactically also form a similar
intonation pattern. This explains how children discover
syllable and word boundaries through prosodic cues. Overall,
prosodic bootstrapping explores determining grammatical groupings in a speech stream rather than learning word meaning. One of the key components of the prosodic bootstrapping hypothesis is that prosodic cues may aid infants in identifying lexical and syntactical properties. From this, three key elements of prosodic bootstrapping can be proposed: The only way that an infant could be born with this ability is if the prosodic patterns of the target language are learned in
utero. Further evidence of young infants using prosodic cues is their ability to discriminate the acoustic property of
pitch change by 1–2 months old.
Prosodic cues for syntactic structure Infants and young children receive much of their language input in the form of
infant-directed speech (IDS) and
child-directed speech (CDS), which are characterized as having exaggerated
prosody and simplification of words and grammar structure. When interacting with infants and children, adults often raise and widen their
pitch, and reduce their speech rate. However, these cues vary across cultures and across languages. There are several ways in which infant- and child-directed speech can facilitate language acquisition. In recent studies, it is shown that IDS and CDS contain prosodic information that may help infants and children distinguish between paralinguistic expressions (e.g. gasps, laughs, expressions) and informative speech. In
Western cultures, mothers speak to their children using exaggerated
intonation and pauses, which offer insight about syntactic groupings such as
noun phrases,
verb phrases, and
prepositional phrases. Consequently, phrases are smaller components of
clauses. For example, "the tall man" or "walks his dog". preferring pauses at clause boundaries illustrates infants' abilities to discriminate clauses in a passage. This reveals that while infants do not understand word meaning, they are in the process of learning about their native language and grammatical structure. In a separate study, Jusczyk reported that 9 month old infants preferred passages with pauses occurring between subject-noun phrases and verb phrases. These results are further evidence of infant sensitivity for syntactic boundaries. In a follow-up study by LouAnn Gerken et al., researchers compared sentences such as (1) and (2). The prosodic boundaries are indicated by parentheses. 5. (Joe)(kissed the dog). 6. (He kissed)(the dog). In (1), there is a pause before the verb . This is also the location of the subject-verb phrase boundary. Comparably in (2), which contains a
weak pronoun, speakers either do not produce a salient prosodic boundary or place the boundary after the verb . When tested, 9 month old infants illustrated a preference for pauses located before the verb, such as in (1). However, when passages with
pronoun subjects were used, such as in (2), infants did not show a preference for where the pause occurs. While these results again illustrate that infants are sensitive to prosodic cues in speech, they introduce evidence that infants prefer prosodic boundaries that occur naturally in speech. Although the use of prosody in infant speech processing is generally viewed as assisting infants in speech parsing, it has not yet been established how this
speech segmentation enriches the acquisition of syntax.
Criticism Critics of
prosodic bootstrapping have argued that the reliability of prosodic cues has been overestimated and that prosodic boundaries do not always match up with syntactic boundaries. It is argued instead that while prosody does provide infants and children useful clues about a language, it does not explain how children learn to combine clauses, phrases, and sentences, nor word meaning. As a result, a comprehensive account of how children learn language must combine
prosodic bootstrapping with other types of bootstrapping as well as more general learning mechanisms. ==Pragmatic bootstrapping==