This study investigated how infants deal with cross-talker variability in the perception of native lexical tones, paying specific attention to developmental changes and the role of task demands. Using the habituation-based visual fixation procedures, we tested Cantonese-learning infants of different age groups on their ability to discriminate Cantonese Tone 1 (high level) and Tone 3 (mid level) produced by either multiple talkers or a single talker. Results demonstrated that the 12-month-old and 24-month-old groups showed reliable discrimination across talkers, whereas the 18-month-old group did not (Experiment 1), despite their ability to discriminate the same contrast when the talker was held constant (Experiment 2). In a task that included a novel object as a referent to the sound, the 18-month-olds discriminated the contrast across talkers from Tone 1 to Tone 3 (Experiment 3). These results revealed a U-shaped developmental path and perceptual asymmetry in native lexical tone discrimination across talkers.

This longitudinal study investigated modifications in lexical tones and intonation in Cantonese infant-directed speech (IDS) to children aged 15 and 23 months. The results showed that to children at both ages, mothers increased intonational pitch height and pitch variability across utterances, and produced lexical tones with generally larger tonal space and greater intra-talker tone variation within categories in IDS compared to adult-directed speech. No significant changes were found in either lexical tones or intonation in IDS between the two ages. In addition, positive correlations were found between the degree of age-related changes in tonal space and intonational exaggerations in IDS as children grow older. The findings were discussed with a focus on the co-occurrence of an increase in tone variation along with tonal space expansion, the age-related changes in lexical tones and intonation, and the associations between the lexical and prosodic pitch modifications.

A 15-month-old child underwent percutaneous expansion of a Melody transcatheter pulmonary valve in the mitral position to accommodate growth after initial surgical implantation during infancy, but transiently decompensated after valvuloplasty owing to stent malformation. The Melody valve in the mitral position of small patients can be further expanded by percutaneous dilation, but there are a number of potential complications and technical improvements to consider.

The current study aims to make an initial neuroimaging contribution to central implicit-explicit issues in second language (L2) acquisition by considering how implicit and explicit contexts mediate the neural representation of L2. Focusing on implicit contexts, the study employs a longitudinal design to examine the neural representation of L2 syntax and also considers how the neural circuits underlying L2 syntax vary among learners who exhibit different levels of performance on linguistic and cognitive tasks. Results suggest that when exposed to a L2 under an implicit context, some learners are able to quickly rely on neural circuits associated with first language grammar and procedural memory, whereas other learners increasingly use extralinguistic neural circuits related to control mechanisms to process syntax. Thus, there may be multiple ways in which L2 is represented neurally, at least when learned under implicit contexts.

The mechanisms that allow for both language-specific and universal constraints in language development are not fully understood. According to the rhythm detection hypothesis, sensitivity to rhythm is the underlying mechanism that is fundamental to language development. Support from a number of Western languages, as well as Mandarin, has led to the proposal that rhythm detection may provide a language-universal account of language development. However, claims of universality may be premature because most research has addressed reading (rather than language) development, only a small number of languages have been investigated, and pitch is a better predictor of reading than rhythm in Mandarin children. Therefore, we examined language development using a narrative story-retelling task in children who speak Cantonese (a more complex tone inventory than Mandarin) and also assessed temporal and pitch-based auditory abilities to consider whether temporal processing drives development in a tone language. Both temporal and pitch abilities correlated with language development, but only pitch explained unique variance in language after age. The findings support the role of basic auditory processing mechanisms in language development, but they extend beyond the rhythm detection hypothesis by demonstrating that the fundamental cues for development are dependent on the specific processing demands of each language, rather than being universal.

Numerous factors are thought to be advantageous for non-native language learning although they are typically investigated in isolation, and the interaction between them is not understood. Firstly, bilinguals are claimed to acquire a third language easier than monolinguals acquire a second. Secondly, closely related languages may be easier to learn. Thirdly, certain phonetic features could be universally more difficult to acquire. We tested these hypotheses used as explanations by having adults learn vocabularies that differentiated words using foreign phonetic contrasts. In Experiment 1, Mandarin–English bilinguals outlearned English monolinguals, and the Mandarin-like (retroflex) artificial language was better learned than the English-like (fricative voicing). In Experiment 2, bilinguals again outlearned English monolinguals for the Mandarin-like artificial language. However, only Korean–English bilinguals showed an advantage for the more difficult Korean-like (lenition) language. Bilinguals, relative to monolinguals, show a general advantage when learning ‘easy’ contrasts, but phonetic similarity to the native language is useful for learning universally ‘difficult’ contrasts.

This study examined how individual differences in cognitive abilities account for variance in the attainment level of adult second language (L2) syntactic development. Participants completed assessments of declarative and procedural learning abilities. They subsequently learned an artificial L2 under implicit training conditions and received extended comprehension and production practice using the L2. Syntactic development was assessed at both early and late stages of acquisition. Results indicated positive relationships between declarative learning ability and syntactic development at early stages of acquisition and between procedural learning ability and development at later stages of acquisition. Individual differences in these memory abilities accounted for a large amount of variance at both stages of development. The findings are consistent with theoretical perspectives of L2 that posit different roles for these memory systems at different stages of development, and suggest that declarative and procedural memory learning abilities may predict L2 grammatical development, at least for implicitly trained learners.

The present randomised parallel study assessed the impact of adding MUFA to a dietary portfolio of cholesterol-lowering foods on the intravascular kinetics of apoAI- and apoB-containing lipoproteins in subjects with dyslipidaemia. A sample of sixteen men and postmenopausal women consumed a run-in stabilisation diet for 4 weeks. Subjects were then randomly assigned to an experimental dietary portfolio either high or low in MUFA for another 4 weeks. MUFA substituted 13·0 % of total energy from carbohydrate (CHO) in the high-MUFA dietary portfolio. Lipoprotein kinetics were assessed after the run-in and portfolio diets using a primed, constant infusion of [2H3]leucine and multicompartmental modelling. The high-MUFA dietary portfolio resulted in higher apoAI pool size (PS) compared with the low-MUFA dietary portfolio (15·9 % between-diet difference, P= 0·03). This difference appeared to be mainly attributable to a reduction in apoAI fractional catabolic rate (FCR) after the high-MUFA diet ( − 5·6 %, P= 0·02 v. pre-diet values), with no significant change in production rate. The high-MUFA dietary portfolio tended to reduce LDL apoB100 PS compared with the low-MUFA dietary portfolio ( − 28·5 % between-diet difference, P= 0·09), predominantly through an increase in LDL apoB100 FCR (23·2 % between-diet difference, P= 0·04). These data suggest that adding MUFA to a dietary portfolio of cholesterol-lowering foods provides the added advantage of raising HDL primarily through a reduction in HDL clearance rate. Replacing CHO with MUFA in a dietary portfolio may also lead to reductions in LDL apoB100 concentrations primarily by increasing LDL clearance rate, thus potentiating further the well-known cholesterol-lowering effect of this diet.

This paper explores how theories on the relationship between language and domain-general cognitive capabilities might account for individual variation in second language learning. We investigated the acquisition of a morphophonological grammar paired with standardized tests of memory function. The language learned had simple and complex morphophonological patterns of word formation, which are hypothesized to correlate with standardized measures of procedural and declarative memory, respectively. The results show a significant amount of variation in learning success is accounted for by these measures of memory in accordance with the hypothesis. These findings help explain why some adults are able to learn a second language more easily than others while also advancing a model of second language learning motivated by linguistic theory.

The current study investigates the learning of nonnative suprasegmental patterns for word identification. Native English-speaking adults learned to use suprasegmentals (pitch patterns) to identify a vocabulary of six English pseudosyllables superimposed with three pitch patterns (18 words). Successful learning of the vocabulary necessarily entailed learning to use pitch patterns in words. Two major facets of sound-to-word learning were investigated: could native speakers of a nontone language learn the use of pitch patterns for lexical identification, and what effect did more basic auditory ability have on learning success. We found that all subjects improved to a certain degree, although large individual differences were observed. Learning success was found to be associated with the learners' ability to perceive pitch patterns in a nonlexical context and their previous musical experience. These results suggest the importance of a phonetic–phonological–lexical continuity in adult nonnative word learning, including phonological awareness and general auditory ability.