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6.1.8 Summary
While there can be no doubt that experience is necessary for language acquisition, the form of experience can vary widely. The genesis of a new language appears to require the existence of a community, but the ontogenesis of a first language in children can involve different amounts and types of communicative interaction. All normal children appear to contain within themselves the ability to create a language in spite of wide variations in experience.
on this story or another, matched in basic characteristics. For example, the first twenty-eight paragraphs of The Cat in the Hat were compared toThe Dog in the Fog. The newborns showed a significant preference for the target story over the new story, in contrast to control subjects whose mothers had not participated in the study. They even did so with a change in speaker (DeCasper and Spence 1986). When the story was read backwards, the effect disappeared (Mehler et al.
1978).
6.2.1.3 Is one language enough?
Many, if not most, infants are exposed to more than one language. An important series of research studies now confirms that “a few days after birth, infants are able to tell apart two different languages, even when neither of them is present in their environment; moreover, they already show a preference for their maternal language” (Mehler and Christophe 1995, 947). Infants are not confused by exposure to more than one language, and seem to know very early which language is “going to be their maternal language” (948; see appendix 4).
Mehler et al. (1988) tested four-day-old French infants and two-month-old American infants on whether they could distinguish languages. A French–Russian bilingual woman and an Italian–English bilingual woman each recorded a narra- tive in their two languages. French infants showed a greater arousal to French than to Russian. American infants distinguished English and Italian.23Two-day-olds whose mothers were either English or Spanish monolinguals, tested with audio recordings of monolingual speakers of Spanish or English, “activated recordings of their native language for longer periods than the foreign language” (Moon, Cooper and Fifer 1993, 495).
When two-month-old English infants were tested on sentences half in English and half in Japanese (recorded by four female native English speakers and four female native Japanese speakers), they distinguished their mother tongue and the foreign language; language change had a significantly greater effect than speaker change (Hesketh, Christophe and Dehaene-Lambertz 1997). Similar results were found with French three-day-olds (Nazzi et al. 1998). Five-month-old infants responded to new utterances in a new language significantly more than to new utterances in the same language, as with English compared to Spanish (Bahrick and Pickens 1988). Infants thus not only discriminate, but categorize sounds by language.
More recent research has confirmed that neonates (at four days) can discrim- inate “two unfamiliar languages without any difficulty” (Mehler and Christophe 1995, 946).24 French newborns distinguish English and Italian or English and
23Although the American infants did not show a significant preference for the English sample in this early research, subsequent research confirmed this preference (Mehler and Christophe 1995 reporting research by Lambertz).
24The results of the Mehler et al. 1988 study at first suggested that infants were not able to distinguish unfamiliar languages, and that familiarity with one language was necessary in order to achieve this effect. Mehler and Christophe 1995 report a reanalysis of the original data and disconfirm this.
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Table 6.1 Language discrimination by infants (neonates to four to five months) (*=no discrimination).
Neonates Language Contrast Reference
(French) French–Russian Mehler et al. 1988
English–Japanese Nazzi et al. 1998
*English–German Nazzi et al. 1998
*English–Dutch Nazzi et al. 1998
(English) English–Italian Mehler et al. 1988
English–Spanish Moon et al. 1993
(Spanish) English–Spanish Moon et al. 1993
2 months
(English) *French–Russian Mehler et al. 1988
English–Italian Mehler et al. 1988 4–5 months
(English) English–Dutch Nazzi et al. 1998
(Spanish, Catalan) Spanish–Catalan Bosch and Sebastian-Galles 1997 (Spanish–Catalan bilinguals) *Spanish–Catalan Bosch and Sebastian-Galles 1997
Japanese (Nazzi et al. 1998). However, two-month-olds have been foundnotto make some distinctions between two unfamiliar languages – which the newborn does – although they continue to differentiate their native language from others.
Two-month-old American infants appear not to distinguish French and Russian, although neonates do (Mehler et al. 1988). Older infants may “already concen- trate on utterances that share a structure corresponding to the maternal language and neglect utterances that do not . . . by the age of two months the infant has set the first values to individuate the structure of the maternal language” (947).
Bilingual infants
Infant discrimination varies with whether the child is in a monolingual or bilingual environment. Four-month-old monolinguals (either Spanish or Catalan) were found to distinguish Catalan vs. Spanish (Bosch and Sebastian-Galles 1997, 37). However, infants being raised in Catalan–Spanish bilingual environments showed no preference for either of the familiar languages, but did distinguish a foreign language (e.g., English or Italian).
Table 6.1 summarizes language discrimination results in infants from birth to four to five months of age.
What are the mechanisms by which the infant makes such early distinctions between languages? Several of the infant discriminations persist with low-pass fil- tered stimuli (where only low frequency, e.g., less than 400 HZ, is available), elim- inating much of the segmental information and leaving suprasegmental prosodic features. Suprasegmental (e.g., rhythmic or prosodic) characteristics of the lan- guages thus appear to affect the infant’s discrimination. Although French new- borns discriminate British English and Japanese, which differ in certain rhythmic
properties, they do not discriminate British English and Dutch, which share them (Nazzi et al. 1998). If speech is played backwards, these discriminations disap- pear. (See Ramus et al. 1999 for a comprehensive study of this issue.)
These facts led to new hypotheses regarding the linguistic features used by infants when they represent language at early periods (Ramus et al. 1999), target- ing selected prosodic properties in the infant’s initial representations.25However, the Spanish–Catalan distinction made by four-month-old infants would require recognition of lower level units, since these are “both Romance languages which present differences at the segmental level and at the syllable level, but have impor- tant similarities concerning prosodic structure” (Bosch and Sebastian-Galles 1997, 61).26
Non-human primates (cotton-top tamarin monkeys) have also distinguished Dutch and Japanese language stimuli, suggesting that this discrimination may at least partially involve “general processes of the primate auditory system” (Ramus et al. 2000). However, it is not necessary that human and non-human primates accomplish this cross-language discrimination in the same way, i.e., by using the same cues. Human infants’ distinct capacity may lie precisely in the ability to integrate a rhythmic sensitivity with other aspects of language knowledge. (See Werker and Vouloumanos 2000 for discussion.27)
6.2.2 Summary
Regardless of the precise mechanisms used, human infants show a marvelously quick, differentiated, effective approach to experience of language, one which may begin even before birth. Infants show an initial powerful discrim- ination of, and classification of, the continuous speech stream.
The results above are consistent with the first priorities of an innate Language Faculty; i.e., infants have the initial means to discriminate language from non- language stimuli, and an initial way of “representing input signals” of language (cf. chapter 4). The infants “form a representation of one language and compare results from the new language with their representation” (Ramus et al. 1999, 280).
The results show how marvelously tuned to linguistic data infants are, and how easily linguistic experience can have an effect.