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J Bertoncini

Publications and source records attributed to J Bertoncini.

At least 19 recordsLinked to original sources
PubMed1998

Language discrimination by newborns: toward an understanding of the role of rhythm.

Three experiments investigated the ability of French newborns to discriminate between sets of sentences in different foreign languages. The sentences were low-pass filtered to reduce segmental information while sparing prosodic information. Infants discriminated between stress-timed English and mora-timed Japanese (Experiment 1) but failed to discriminate between stress-timed English and stress-timed Dutch (Experiment 2). In Experiment 3, infants heard different combinations of sentences from English, Dutch, Spanish, and Italian. Discrimination was observed only when English and Dutch sentences were contrasted with Spanish and Italian sentences. These results suggest that newborns use prosodic and, more specifically, rhythmic information to classify utterances into broad language classes defined according to global rhythmic properties. Implications of this for the acquisition of the rhythmic properties of the native language are discussed.

Analysis of Variance↗
PubMed1997

High-amplitude sucking and newborns: the quest for underlying mechanisms.

This study seeks to determine whether newborns are sensitive to an operant-conditioning task involving an unprepared relation between a response and a stimulus. The High-Amplitude Sucking procedure, which is based on such a relation by reinforcing nonnutritive sucking with auditory stimulation, was used. In order to verify that newborns learn the contingency between sucks and sounds in the HAS paradigm, three experiments were carried out. In Experiment 1, the effect of contingent versus noncontingent presentation of speech sounds on newborns' sucking activity was investigated during the minutes following a silent baseline. In contrast to what has been reported with 2-month-old infants in HAS, contingently stimulated newborns did not differ significantly from a nonstimulated control group. Experiment 2 showed that an increase in sucking rates could be obtained after a stimulus change, when sounds were presented contingently, but not when sounds were presented noncontingently. Experiment 3 demonstrated that newborns' sucking responses were reinforced by variation in the presented speech sounds. The results of these three experiments support the hypothesis that newborns tested under the HAS procedure are involved in an operant-learning situation. Implications for learning in neonates and possible differences with older infants are discussed.

Child, Preschool↗
PubMed1997

Newborns discriminate the rhythm of multisyllabic stressed words.

Three experiments were run to test whether newborns were able to discriminate different stress patterns in multisyllabic stressed Italian words that varied both in consonants and in number of syllables. A high-amplitude sucking procedure was adopted in which the experimental group heard 2 sets of stimuli alternating minute by minute, whereas the control group heard only a single set of stimuli. The results showed that stress patterns were discriminated in 2 disyllabic phonetically unvaried words (Experiment 1), in 2 trisyliabic consonant-varied words (Experiment 2), and in 2 sets of disyllabic words varied in consonants within and between words (Experiment 3). The alternation procedure proved to be suitable for examining newborns abilities of discrimination and categorization. It also lowered the participants rejection rate compared with the classic habituation procedure. The present results suggest that newborns are sensitive to words' rhythm, as carried by stress patterns, and that this prosodic information is salient even in the presence of substantial consonant variation.

Arousal↗
PubMed1997

Do weak syllables count for newborns?

Does the newborn's well-known sensitivity to human speech include awareness of the distinction between strong and weak syllables, as has been shown for older infants and adults? The non-nutritive high-amplitude sucking paradigm was used to investigate whether weak syllables play a role in neonate perceptual representation. Two-day-old French infants were tested on their capacity to discriminate phonetically highly varied words containing syllables with various strong vowels versus the weak, reduced vowel schwa in natural, isolated English words. Twenty infants heard lists of weak-strong and lists of strong words (e.g., belief, control, etc. versus nose, dream, etc.) and 20 heard lists of weak-strong and strong-strong words (e.g., belief, control, etc. versus volume, rhubarb, etc.). The results show that weak-strong words were reliably distinguished from strong words, but not from strong-strong words. Taken together, the findings indicate that a weak, reduced vowel is equivalent to a strong, full vowel to the extent that both count as syllabic nuclei. Moreover, this global equivalence in terms of number of syllabic constituents apparently over-rules the more local acoustic difference between strong and weak vowels. The role of syllabic/vocalic information in neonate representation is discussed.

Humans↗
PubMed1997

Organization and discrimination of repeating sound sequences by newborn infants.

A study was conducted to determine whether newborn infants organize auditory streams in a manner similar to that of adults. A series of three experiments investigated the ability of 3- to 4-day-old infants to discriminate repeated rising and falling four-tone sequences in two configurations of source timbre and spatial position. It was hypothesized that if the sequences were organized into two auditory streams on the basis of timbre and spatial position, one of the configurations should be discriminable from its reversal while the other should not. The sequences were tested with different pitch and temporal intervals separating the tones. Sequences were discriminated for the first configuration by adults at both fast tempo/small interval and slow tempo/large interval combinations, while only the latter was discriminated by newborns as measured with a non-nutritive high-amplitude sucking paradigm. Neither adults nor infants could discriminate the sequence reversals for the second configuration. The results suggest that newborn infants organize auditory streams on the basis of source timbre and/or spatial position. They also suggest that newborns have limits in temporal and/or pitch resolution when discriminating tone sequences.

Auditory Perception↗
PubMed1994

Detection of p53 gene mutation in cancer tissues by nonradioactive direct sequencing.

A simple procedure for direct sequencing of double-stranded PCR products by the dideoxy-termination method has been developed using biotinylated sequencing primers. Sequences of the p53 gene have been obtained from DNA extracted from frozen and formalin-fixed paraffin-embedded cancer tissues. Detection of sequencing ladders was done with chemiluminescent or colorimetric techniques. Both are highly sensitive, but colorimetric detection is less prone to diffusion artifacts, which are common in G-rich regions. Use of this nonradioactive PCR-sequencing protocol allowed rapid and simple determination of p53 gene alterations in human tumors.

Base Sequence↗
PubMed1994

Do infants perceive word boundaries? An empirical study of the bootstrapping of lexical acquisition.

Babies, like adults, hear mostly continuous speech. Unlike adults, however, they are not acquainted with the words that constitute the utterances; yet in order to construct representations for words, they have to retrieve them from the speech wave. Given the apparent lack of obvious cues to word boundaries (such as pauses between words), this is not a trivial problem. Among the several mechanisms that could be explored to solve this bootstrapping problem for lexical acquisition, a tentative but reasonable one posits the existence of some cues (other than silence) that signal word boundaries. In order to test this hypothesis, infants were used as informants in our experiments. It was hypothesized that if word boundary cues exist, and if infants are to use them in the course of language acquisition, then they should at least perceive these cues. As a consequence, infants should be able to discriminate sequences that contain a word boundary from those that do not. A number of bisyllabic stimuli were extracted either from within French words (e.g., mati in mathématicien), or from between words (e.g., mati in panorama typique). Three-day-old infants were tested with a non-nutritive sucking paradigm, and the results of two experiments suggest that infants can discriminate between items that contain a word boundary and items that do not. It is therefore conceivable that newborns are already sensitive to cues that correlate with word boundaries. This result lends plausibility to the hypothesis that infants might use word boundary cues during lexical acquisition.

Arousal↗
PubMed1989

Dichotic perception and laterality in neonates.

Groups of 4-day-old neonates were tested for dichotic discrimination and ear differences with the High-Amplitude-Sucking procedure. In the first experiment, dichotic speech discrimination was attested by comparison with a control group. Furthermore, among those subjects who showed a substantial recovery of sucking response at least after one of the two syllable changes, it was observed that significantly more subjects manifested a stronger reaction to a right-ear change than to a left-ear change. In the second experiment, 4-day-old neonates were tested on syllable and music timbre discrimination. The significant Stimulus Type x Ear interaction observed suggests perceptual asymmetries indicative of very precocious brain specialization.

Arousal↗
PubMed1988

An investigation of young infants' perceptual representations of speech sounds.

The present study examined the ability of newborns and 2-month-olds to detect phonetic differences between syllables. By relying on the modified high-amplitude sucking procedure, which did not permit the infants to use a simple same-different response, the present experiments tapped the perceptual representations of the speech sounds. Infants as young as a few days old displayed some capacity to represent differences in a set of syllables varying in their phonetic composition, although there was no convincing evidence that their representations were structured in terms of phonetic segments. Finally, evidence of developmental changes in speech processing were noted for the first time with infants in this age range. The change noted was a tendency from global toward more specific representations on the part of the older infants.

Arousal↗
PubMed1987

Discrimination in neonates of very short CVs.

The experiment reported here explores the ability of 4- to 5-day-old neonates to discriminate consonantal place of articulation and vowel quality using shortened CV syllables similar to those used by Blumstein and Stevens [J. Acoust. Soc. Am. 67, 648-662 (1980)], without vowel steady-state information. The results show that the initial 34-44 ms of CV stimuli provide infants with sufficient information to discriminate place of articulation differences in stop consonants ([ba] vs [da], [ba] vs [ga], [bi] vs [di], and [bi] vs [gi]) and following vowel quality ([ba] vs [bi], [da] vs [di], and [ga] vs [gi]). These results suggest that infants can discriminate syllables on the basis of the onset properties of CV signals. Furthermore, this experiment indicates that neonates require little or no exposure to speech to succeed in such a discrimination task.

Female↗
PubMed1986

Respiratory mechanics in men following a deep air dive.

The mechanical properties of the lungs were measured in 10 men before and after a simulated air dive to 285 ft of seawater (87 m). The objective was to determine whether a dive likely to produce pulmonary bubble emboli would alter lung mechanics. Lung function was measured predive and at 1, 2, 3, 6, 7, and 23 h postdive. Measurements of lung function were also made at identical times on a control day when no dive was made. Each set of measurements included precordial Doppler signals, pulmonary resistance, quasistatic lung compliance, forced vital capacity (FVC), forced expired volume after 1.0 s (FEV 1.0), the ratio of FEV 1.0 to FVC (FEV 1.0/FVC%), and maximal airflow after 50 and 75% of the vital capacity had been expired (Vmax50 and Vmax75, respectively). Base-line measurements of pulmonary resistance and quasistatic compliance were normal in all subjects. FVC and FEV 1.0 were greater than predicted for most subjects and were increased proportionately so that the FEV 1.0/FVC% was normal. Following the dive, bubble signals were heard in four subjects, and two subjects had mild symptoms of decompression sickness. No subject demonstrated any alteration in lung function that could be attributed to the dive. We concluded that stressful decompressions capable of producing "silent" pulmonary bubble emboli do not alter lung mechanics.

Adult↗
PubMed1980

[Language perception in the newborn infant: some observations].

Initial state dispositions in the new-born infant allow him/her to perceive linguistically pertinent speech differences in a manner comparable to that of adults. The specificity of language processing based on the categorical perception of speech stimuli is questioned. Our studies are now oriented towards defining the status of the syllable as a perceptive unit in language. A further area of research is proposed, based on the study of the supra-segmental properties of language on which the infant can base his recognition of the speaker.

Auditory Perception↗
PubMed1978

Infant recognition of mother's voice.

Each of a group of one-month-old infants was reinforced, contingent upon nonutritive sucking, with its mother's voice and the voice of a stranger. In this experiment, two conditions were applied. Under the first, the mother's speech was aimed at communicating with the infant, while, under the second, the mother's speech lacked prosodic and intonational aspects of normal speech. It was shown that infants will suck more for their mother's voices under the intonanted condition only. It was concluded that a young infant prefers its own mother's voice provided the mother speaks normally.

Discrimination, Psychological↗
PubMedDate not supplied

Morae and syllables: rhythmical basis of speech representations in neonates.

Are neonates sensitive to the different rhythmical units that are used in different spoken languages? And do they use these units to represent and discriminate multisyllabic words? In the present study, we used the High-Amplitude Sucking procedure to test whether 3-day-old French infants discriminate lists of Japanese words. The lists of words differed either in the number of syllabic units or in the number of sub-syllabic units such as morae. In Experiment 1, infants heard bisyllabic versus trisyllabic words (e.g.: iga vs. hekiga); in Experiment 2, they were presented with bimoraic versus trimoraic bisyllabic words (e.g.: iga vs. iNga). The results corroborate those obtained by Bijeljac-Babic, Bertoncini, and Mehler (1993), providing further evidence that neonates discriminate bisyllabic from trisyllabic words. In contrast, neonates do not appear to discriminate bisyllabic words that vary in number of sub-syllabic units. It is proposed that syllables are particularly salient units during the initial stage of speech processing, irrespective of which language and rhythmical structure is heard.

Electronic Data Processing↗