Developmental Science最新文献

The MacArthur-Bates Communicative Development Inventories (CDI) are widely used, parent-report instruments of language acquisition. Here, we focus on the word-inventory sections of the instruments, and show two different approaches to modeling CDI data, based on real-world needs. First, we show that Words & Gestures data collected out-of-age-normed-range can be robustly adjusted to Words & Sentences scores. Second, we demonstrate a novel application of Gompertz growth curves to longitudinal CDI data, especially when the same timepoints were not collected between individuals (i.e., an accelerated longitudinal design). Gompertz curves provide a “growth rate” or an “age at maximum growth” parameter that can be used to summarize vocabulary development. We compare these parameters between healthy developing children in two longitudinal cohorts, as well as a cohort of children with a diagnosis of speech disorder, language disorder, or learning or reading disability, who we show to have lower growth rates. We hope these analyses and results inform future work on longitudinal CDI analyses.

At the physical level, the experience of pitch has a single determinant: the repetition rate of a waveform in the acoustic signal. Yet, psychologists describe pitch as composed of two perceptual dimensions, height and chroma. Chroma accounts for octave equivalence, whereby sounds with fundamental frequencies at a 1:2 ratio are perceived as sharing the same pitch. A current controversy debates whether chroma is a basic perceptual property dependent on biological constraints or a higher-order cognitive construct shaped by culture. Here, we used high-density electroencephalography (EEG) and time-resolved multivariate pattern analyses to characterize pitch processing in humans at 3 months of age. We found that, when exposed to repetitive sequences of orchestral tones, infants encode two separate pitch-related dimensions automatically and with divergent dynamics. Namely, our classifiers isolated height-specific information from the neural signal rapidly after the onset of the auditory sequences. Beyond approximately 600 ms, the performance of pitch height decoders fell to chance level and did not recover. In contrast, neural patterns displaying octave equivalence were retrieved later in the trial, over multiple time windows throughout the unfolding of the auditory sequence, and after sequence offset. Overall, this study reveals that very early in human development, the pitch of naturally rich tones is processed over two distinct encoding stages, capturing not only their absolute height but also their relative position in the octave. We speculate that separate encoding mechanisms reflect distinct functional roles carried by the two dimensions.

Touch is an extraordinary sensory, communicative, and affective experience that has cascading positive effects on infants’ socio-emotional development and neurobiological functioning. This study aims to explore whether maternal touch can influence infants’ well-known attentional biases toward fearful facial expressions. Visual behaviour of 7-month-old infants was measured through an eye-tracker while they were presented with an overlap task in which a central emotional face (happy, neutral, and fearful) was followed by a peripheral distractor. During the task, infants were randomly assigned to two experimental groups. In one group, the mother kept the hand on the infant's lap (Touch group, N = 24), while in another group, the mother was present but not in tactile contact with the infant (No-Touch condition, N = 24). Also, the frequency of spontaneous maternal touch was assessed during mother-infant free-play interaction. Results showed an overall increase in the proportion of looking times (PTs) toward the fear stimulus compared to the other emotional stimuli. Further, only the group of infants that were in tactile contact with their mothers showed slower disengagement times (DTs) from fearful faces compared to happy and neutral emotions. Finally, in the No-Touch condition, infants who experienced more regulatory touch (massages and caresses) when interacting with their mother showed increased attention toward threatening (Fearful faces) and ambiguous (Neutral faces) emotional signals. Vice versa, increased frequency with other forms of touch (i.e., dynamic and static) during the interaction was associated with decreased attention toward the negative and neutral facial expressions. Our findings suggest that maternal touch provides a relevant communicative signal to the infant that indicates that it is safe to process fearful stimuli, favoring infants’ knowledge and learning of their social world.

Most behavioral interventions on reading disability (RD) have been developed in alphabetic languages and are phonologically-based. Chinese is a morpho-syllabic language in which each character represents a morpheme and a syllable. Therefore, phonologically-based interventions may not be most helpful in Chinese. In this study, we compared a phonological and a morphological intervention (MI) in Chinese children with RD both behaviorally and neurologically. We recruited 80 fifth-grade Chinese children, including 18 typically developing children as age controls (AC), and 62 children with RD, 22 of whom received the phonological intervention (PI), 22 of whom received the MI, and 18 served as waiting-list controls (WL). An auditory rhyming task and a visual spelling task were employed to examine brain activation before and after the intervention. We found that the PI and MI both effectively improved character naming, sentence reading fluency, one-minute irregular character reading and phonological awareness compared with the WL group. At the brain level, the PI group showed greater increase of brain activation in the right middle temporal gyrus than the MI and WL following the intervention in an auditory rhyming task, suggesting compensatory phonological strategies developed in PI. The MI group showed greater increase of brain activation in the left middle frontal gyrus, left inferior frontal gyrus and left fusiform gyrus than the PI and the WL group following the intervention in a visual spelling task, suggesting functional normalization, because these regions were less activated in children with RD than typical controls before the intervention. These findings suggest intervention-specific brain changes with otherwise similar effectiveness in the behavior. It provides important insights in understanding brain mechanisms underlying behavioral intervention in children with RD.

Trial Registration: This study's design was preregistered at the Chinese Clinical Trial Registry (ChiCTR2300067536), see [https://www.chictr.org.cn]

The present study assessed the structural and functional representation of the upper limb in a large cohort (N = 84) of typically developing children aged 6 to 10. The first task aimed at obtaining a structural measure of the representation of the arm, specifically the two segments that compose it: the forearm and the hand. Participants were asked to localize three landmarks (elbow, wrist, and tip of the middle finger) while blindfolded and upon tactile stimulation of the three landmarks. The second task required a functional estimation of the represented length of the arm. Participants judged whether their arm fully outstretched would be long enough to touch an object presented at seven different distances without being allowed to perform the movement. The two tasks revealed opposite patterns of (mis-)representation. At the structural level, the hand length was underestimated, while the forearm representation matched the actual size. This resulted in an underestimation of total arm length in the structural task. At the functional level, total arm length was overestimated across all age groups. Moreover, there was no relationship between estimates on the structural and functional tasks. These results support the coexistence of multiple, independent body representations in children.