Input effects on the acquisition of a novel phrasal construction in five year olds

The present experiments demonstrate that children as young as five years old (M = 5;2) generalize beyond their input on the basis of minimal exposure to a novel argument structure construction. The novel construction that was used involved a non-English phrasal pattern: VN1N2, paired with a novel abstract meaning: N2 approaches N1. At the same time, we find that children are keenly sensitive to the input: they show knowledge of the construction after a single day of exposure but this grows stronger after three days; also, children generalize more readily to new verbs when the input contains more than one verb

High or low? Comparing high and low-variability phonetic training in adult and child second language learners

Background High talker variability (i.e., multiple voices in the input) has been found effective in training nonnative phonetic contrasts in adults. A small number of studies suggest that children also benefit from high-variability phonetic training with some evidence that they show greater learning (more plasticity) than adults given matched input, although results are mixed. However, no study has directly compared the effectiveness of high versus low talker variability in children. Methods Native Greek-speaking eight-year-olds (N = 52), and adults (N = 41) were exposed to the English /i/-/ɪ/ contrast in 10 training sessions through a computerized word-learning game. Pre- and post-training tests examined discrimination of the contrast as well as lexical learning. Participants were randomly assigned to high (four talkers) or low (one talker) variability training conditions. Results Both age groups improved during training, and both improved more while trained with a single talker. Results of a three-interval oddity discrimination test did not show the predicted benefit of high-variability training in either age group. Instead, children showed an effect in the reverse direction—i.e., reliably greater improvements in discrimination following single talker training, even for untrained generalization items, although the result is qualified by (accidental) differences between participant groups at pre-test. Adults showed a numeric advantage for high-variability but were inconsistent with respect to voice and word novelty. In addition, no effect of variability was found for lexical learning. There was no evidence of greater plasticity for phonetic learning in child learners. Discussion This paper adds to the handful of studies demonstrating that, like adults, child learners can improve their discrimination of a phonetic contrast via computerized training. There was no evidence of a benefit of training with multiple talkers, either for discrimination or word learning. The results also do not support the findings of greater plasticity in child learners found in a previous paper (Giannakopoulou, Uther & Ylinen, 2013a). We discuss these results in terms of various differences between training and test tasks used in the current work compared with previous literature

Onomatopoeia, gestures, actions and words: How do caregivers use multimodal cues to communicate with their children

Most research on how children learn the mapping between words and world has assumed that language is arbitrary, and has investigated language learning in contexts in which objects referred to are present in the environment. Here, we report analyses of a semi-naturalistic corpus of caregivers talking to their 2-3 year-old. We focus on caregivers’ use of non-arbitrary cues across different expressive channels: both iconic (onomatopoeia and representational gestures) and indexical (points and actions with objects). We ask if these cues are used differently when talking about objects known or unknown to the child, and when the referred objects are present or absent. We hypothesize that caregivers would use these cues more often with objects novel to the child. Moreover, they would use the iconic cues especially when objects are absent because iconic cues bring to the mind’s eye properties of referents. We find that cue distribution differs: all cues except points are more common for unknown objects indicating their potential role in learning; onomatopoeia and representational gestures are more common for displaced contexts whereas indexical cues are more common when objects are present. Thus, caregivers provide multimodal non-arbitrary cues to support children’s vocabulary learning and iconicity – specifically – can support linking mental representations for objects and labels

X-ray Spectra of the RIXOS source sample

We present results of an extensive study of the X-ray spectral properties of sources detected in the RIXOS survey, that is nearly complete down to a flux limit of 3e-14 cgs (0.5-2 keV). We show that for X-ray surveys containing sources with low count rate spectral slopes estimated using simple hardness ratios in the ROSAT band can be biased. Instead we analyse three-colour X-ray data using statistical techniques appropriate to the Poisson regime which removes the effects of this bias. We have then applied this technique to the RIXOS survey to study the spectral properties of the sample. For the AGN we find an average energy index of 1.05+-0.05 with no evidence for spectral evolution with redshift. Individual AGN are shown to have a range of properties including soft X-ray excesses and intrinsic absorption. Narrow Emission Line Galaxies also seem to fit to a power-law spectrum, which may indicate a non-thermal origin for their X-ray emission. We infer that most of the clusters in the sample have a bremsstrahlung temperature >3 keV, although some show evidence for a cooling flow. The stars deviate strongly from a power-law model but fit to a thermal model. Finally, we have analysed the whole RIXOS sample containing 1762 sources. We find that the mean spectral slope of the sources hardens at lower fluxes in agreement with results from other samples. However, a study of the individual sources demonstrates that the hardening of the mean is caused by the appearance of a population of very hard sources at the lowest fluxes. This has implications for the nature of the soft X-ray background.Comment: 31,LaTeX file, 2 PS files with Table 2 and 22 PS figures. MNRAS in pres

Onomatopoeia, gestures, actions and words: how do caregivers use multimodal cues in their communication to children?

Most research on how children learn the mapping between words and world has assumed that language is arbitrary, and has investigated language learning in contexts in which objects referred to are present in the environment. Here, we report analyses of a semi-naturalistic corpus of caregivers talking to their 2-3 year-old. We focus on caregivers’ use of non-arbitrary cues across different expressive channels: both iconic (onomatopoeia and representational gestures) and indexical (points and actions with objects). We ask if these cues are used differently when talking about objects known or unknown to the child, and when the referred objects are present or absent. We hypothesize that caregivers would use these cues more often with objects novel to the child. Moreover, they would use the iconic cues especially when objects are absent because iconic cues bring to the mind’s eye properties of referents. We find that cue distribution differs: all cues except points are more common for unknown objects indicating their potential role in learning; onomatopoeia and representational gestures are more common for displaced contexts whereas indexical cues are more common when objects are present. Thus, caregivers provide multimodal non-arbitrary cues to support children’s vocabulary learning and iconicity – specifically – can support linking mental representations for objects and labels

Spatial Autocorrelation Models for Galton's Problem

The effects of Galton's problem are discussed within a framework provided by the linear regression model. We examine five illustrative diffusion models and evaluate alternative estimation procedures (es pecially Naroll's linked pairs test and Wirsing's second order partial correlation). While no one procedure is adequate for all models, the specification of a diffusion model provides guidance in the selection of an appropriate estimation procedure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68209/2/10.1177_106939718101600106.pd

The role of input variability and learner age in second language vocabulary learning

Input variability is key in many aspects of linguistic learning, yet variability increases input complexity, which may cause difficulty in some learning contexts. The current work investigates this trade-off by comparing speaker variability effects on L2 vocabulary learning in different age-groups. Existing literature suggests that speaker variability benefits L2 vocabulary learning in adults, but this may not be the case for younger learners. In this study, native English-speaking adults, 7-8 year-olds, and 10-11 year-olds learned six novel Lithuanian words from a single speaker, and six from eight speakers. In line with previous research, adults showed better production of the multi-speaker items at test. No such benefit was found for either group of children either in production or comprehension. Children also had greater difficulties in processing multiple-speaker cues during training. We conclude that age-related capacity limitations may constrain the ability to utilise speaker variability when learning words in a new language

Guest Editorial

This is an editorial which introduces original papers produced on the theme of the supervision of social work practiceThis is an Accepted Manuscript of an article published by Taylor & Francis in Practice: Social Work in Action on September 2015, available online: http://dx.doi.org/10.1080/09503153.2015.1048053This guest editorial introduces the special edition on the supervision of social work practic

Nicotinic Acetylcholine Receptors Control Encoding and Retrieval of Associative Recognition Memory through Plasticity in the Medial Prefrontal Cortex

Summary: Nicotinic acetylcholine receptors (nAChRs) expressed in the medial prefrontal cortex have critical roles in cognitive function. However, whether nAChRs are required for associative recognition memory and the mechanisms by which nAChRs may contribute to mnemonic processing are not known. We demonstrate that nAChRs in the prefrontal cortex exhibit subtype-specific roles in associative memory encoding and retrieval. We present evidence that these separate roles of nAChRs may rely on bidirectional modulation of plasticity at synaptic inputs to the prefrontal cortex that are essential for associative recognition memory. : Sabec et al. reveal a divergence in function of prefrontal nicotinic receptor subtypes in different stages of long-term associative recognition memory that relates to bidirectional modulation of synaptic plasticity at hippocampal-prefrontal synapses. Keywords: acetylcholine, nicotinic receptor, medial prefrontal cortex, associative recognition memory, plasticit