The Language-Specificity of Phonetic Adaptation to Talkers

Listeners adapt efficiently to new talkers by using lexical knowledge to resolve perceptual uncertainty. This adaptation has been widely observed, both in first (L1) and in second languages (L2). Here, adaptation was tested in both the L1 and L2 of speakers of Mandarin and English, two very dissimilar languages. A sound midway between /f/ and /s/ replacing either /f/ or /s/ in Mandarin words presented for lexical decision (e.g., bu4fa3 "illegal"; kuan1song1 "loose") prompted the expected adaptation; it induced an expanded /f/ category in phoneme categorization when it had replaced /f/, but an expanded /s/ category when it had replaced /s/. Both L1 listeners and English-native listeners with L2 Mandarin showed this effect. In English, however (with e.g., traffic; insane), we observed adaptation in L1 but not in L2; Mandarin-native listeners, despite scoring highly in the English lexical decision training, did not adapt their category boundaries for /f/ and /s/. Whether the ambiguous sound appeared syllable-initially (as in Mandarin phonology) versus word-finally (providing more word identity information) made no difference. Perceptual learning for talker adaptation is language-specific in that successful lexically guided adaptation in one language does not guarantee adaptation in other known languages; the enabling conditions for adaptation may be multiple and diverse.

The effect of study-abroad experience on lexical translation among interpreting students

This study investigates the impact of study-abroad experience (SAE) on lexical translation among 50 Chinese (L1)-English (L2) interpreting students. Participants were divided into two groups based on their experience abroad. Both groups consisted of 25 unbalanced L2 learners who were matched in age, working memory, length of interpreting training, and L2 proficiency. Bidirectional word translation recognition tasks, from L1 to L2 and L2 to L1, highlighted several key findings: (1) both groups were significantly more accurate and faster from L2 to L1 than in the reverse direction; (2) the study abroad (SA) group was more inclined to respond quickly at the risk of making errors, whereas the non-study abroad (NSA) group tended to be more cautious, prioritising accuracy over speed; (3) the SA group were more balanced and consistent in their performance across lexical translations in both directions than the NSA group. These results emphasise the potent effect of SAE in resolving bilinguals' language competition, especially in streamlining language switching, a cognitive process critical for interpreting students engaging daily with dual languages.

Corrigendum: Editorial: New approaches to how bilingualism shapes cognition and the brain across the lifespan: beyond the false dichotomy of advantage versus no advantage

[This corrects the article DOI: 10.3389/fpsyg.2023.1149062.].

What interventions and programmes are available to support older nurses in the workplace? A literature review of available evidence

BACKGROUND

High exit rates, stalling entry rates, population ageing, and, most recently, the COVID-19 pandemic have placed significant strain on the world's nursing workforce. Both developed and developing countries face similar predicaments. Evidence-based programmes to support older nurses in the workplace are urgently needed to ensure the sustainability of a career in nursing for this group of healthcare professionals.

OBJECTIVES

To scope and synthesise available evidence on evaluated programmes and interventions implemented to support the ageing nursing workforce's health, wellbeing, and retention.

DESIGN

A literature review of available evidence using a systematic approach.

METHOD

Medline, Scopus, PsycINFO and CINAHL were searched for relevant peer-reviewed evidence. Data from the peer-reviewed literature were extracted separately into purpose designed-extraction spreadsheets. Information relevant to study design, intervention design, outcome constructs, intervention outcomes, and barriers and enablers to intervention success were collected. The protocol for this review was registered in PROSPERO [CRD42021274491].

RESULTS

Eighteen published studies were included in this review. We identified a range of interventions and programmes that have been implemented to support older nurses, which included flexible and reduced work arrangements, mentoring programmes, exercise and lifestyle interventions, continued professional development and purpose-designed remote retreats. We found limited evidence of evaluated outcomes from workplace support interventions that addresses the actual challenges faced by ageing nurses as reported in previous literature reviews. Interventions that were designed to promote a sense of purpose at work resulted in positive outcomes and appeared to more directly address the stated needs of older nurses. Holistic programmes and interventions that could potentially promote both physical well-being and psychological well-being required a broader, whole-of-organisation approach rather than more piecemeal interventions addressing individual physical and mental health concerns. Interventions which acknowledged older nurses' clinical expertise and experience (e.g., mentoring programmes) were linked to positive outcomes.

CONCLUSION

Future intervention efforts should acknowledge and balance intervention participation opportunities against existing everyday workload constraints faced by older nurses. Our review suggests the need for further intervention studies assessing specific outcomes such as psychological and emotional health, as well as interventions that more directly address the most pressing concerns that ageing nurses report at personal and organisational levels. A paradigm shift in productivity measurement in clinical nursing work is required in order to increase the value placed on the unique contribution of older nurses working clinically, particularly in sharing their acquired knowledge, skill, and expertise.

Harnessing automatic speech recognition to realise Sustainable Development Goals 3, 9, and 17 through interdisciplinary partnerships for children with communication disability

PURPOSE

To showcase how applications of automatic speech recognition (ASR) technology could help solve challenges in speech-language pathology practice with children with communication disability, and contribute to the realisation of the Sustainable Development Goals (SDGs).

RESULT

ASR technologies have been developed to address the need for equitable, efficient, and accurate assessment and diagnosis of communication disability in children by automating the transcription and analysis of speech and language samples and supporting dual-language assessment of bilingual children. ASR tools can automate the measurement of and help optimise intervention fidelity. ASR tools can also be used by children to engage in independent speech production practice without relying on feedback from speech-language pathologists (SLPs), thus bridging the long-standing gap between recommended and received intervention intensity. These innovative technologies and tools have been generated from interdisciplinary partnerships between SLPs, engineers, data scientists, and linguists.

CONCLUSION

To advance equitable, efficient, and effective speech-language pathology services for children with communication disability, SLPs would benefit from integrating ASR solutions into their clinical practice. Ongoing interdisciplinary research is needed to further advance ASR technologies to optimise children's outcomes. This commentary paper focusses on industry, innovation and infrastructure (SDG 9) and partnerships for the goals (SDG 17). It also addresses SDG 1, SDG 3, SDG 4, SDG 8, SDG 10, SDG 11, and SDG 16.

Understanding preschoolers' word learning success in different scenarios: disambiguation meets statistical learning and eBook reading

Children's ability to learn new words during their preschool years is crucial for further academic success. Previous research suggests that children rely on different learning mechanisms to acquire new words depending on the available context and linguistic information. To date, there is limited research integrating different paradigms to provide a cohesive view of the mechanisms and processes involved in preschool children's word learning. We presented 4 year-old children (n = 47) with one of three different novel word-learning scenarios to test their ability to connect novel words to their correspondent referents without explicit instruction to do so. The scenarios were tested with three exposure conditions of different nature: (i) mutual exclusivity-target novel word-referent pair presented with a familiar referent, prompting fast-mapping via disambiguation, (ii) cross-situational-target novel word-referent pair presented next to an unfamiliar referent prompting statistically tracking the target pairs across trials, and (iii) eBook - target word-referent pairs presented within an audio-visual electronic storybook (eBook), prompting inferring meaning incidentally. Results show children succeed at learning the new words above chance in all three scenarios, with higher performance in eBook and mutual exclusivity than in cross-situational word learning. This illustrates children's astounding ability to learn while coping with uncertainty and varying degrees of ambiguity, which are common in real-world situations. Findings extend our understanding of how preschoolers learn new words more or less successfully depending on specific word learning scenarios, which should be taken into account when working on vocabulary development for school readiness in the preschool years.

Predicting Mental Health Status in Remote and Rural Farming Communities: Computational Analysis of Text-Based Counseling

Background

Australians living in rural and remote areas are at elevated risk of mental health problems and must overcome barriers to help seeking, such as poor access, stigma, and entrenched stoicism. e-Mental health services circumvent such barriers using technology, and text-based services are particularly well suited to clients concerned with privacy and self-presentation. They allow the client to reflect on the therapy session after it has ended as the chat log is stored on their device. The text also offers researchers an opportunity to analyze language use patterns and explore how these relate to mental health status.

Objective

In this project, we investigated whether computational linguistic techniques can be applied to text-based communications with the goal of identifying a client’s mental health status.

Methods

Client-therapist text messages were analyzed using the Linguistic Inquiry and Word Count tool. We examined whether the resulting word counts related to the participants’ presenting problems or their self-ratings of mental health at the completion of counseling.

Results

The results confirmed that word use patterns could be used to differentiate whether a client had one of the top 3 presenting problems (depression, anxiety, or stress) and, prospectively, to predict their self-rated mental health after counseling had been completed.

Conclusions

These findings suggest that language use patterns are useful for both researchers and clinicians trying to identify individuals at risk of mental health problems, with potential applications in screening and targeted intervention.

Human Echolocators Have Better Localization Off Axis

Here, we report novel empirical results from a psychophysical experiment in which we tested the echolocation abilities of nine blind adult human experts in click-based echolocation. We found that they had better acuity in localizing a target and used lower intensity emissions (i.e., mouth clicks) when a target was placed 45° off to the side compared with when it was placed at 0° (straight ahead). We provide a possible explanation of the behavioral result in terms of binaural-intensity signals, which appear to change more rapidly around 45°. The finding that echolocators have better echo-localization off axis is surprising, because for human source localization (i.e., regular spatial hearing), it is well known that performance is best when targets are straight ahead (0°) and decreases as targets move farther to the side. This may suggest that human echolocation and source hearing rely on different acoustic cues and that human spatial hearing has more facets than previously thought.

Protocol design and preliminary evaluation of the REAL-Health Triple Aim, an open-cohort CVD-care optimisation initiative

Introduction

Effective treatment of cardiovascular disease (CVD) in primary care could be improved. We aim to assess the efficacy of a scalable treatment optimisation programme in unselected community populations in South East England, with the triple aim of improved blood pressure control in people with hypertension, increased high-intensity statin use in people with CVD and reduced gastrointestinal bleeding in patients on antithrombotic medication.

Method

This observational study comprises an open cohort of approximately 200,000 adults at high cardiovascular risk registered with general practitioners in five South East England Clinical Commissioning Groups (CCGs). An intervention programme is planned in four of these CCGs with a further non-intervention CCG acting as a control group. The intervention will consist of: clinical guidelines and educational outreach; virtual patient-reviews software; peer-performance “dashboards” and, where available, financial incentives.

The study will examine 3 primary outcomes: 1. Diagnosed hypertension with a blood pressure <140/90mmHg; 2. Diagnosed CVD on a high-intensity statin; 3. A cardiovascular indication for antithrombotic therapy with one or more factors for increased risk of gastrointestinal bleeding (e.g. age ≥65) on gastroprotection. A further 17 secondary outcomes related to these three aims will be assessed.

Analysis

We will use an interrupted time series analysis over 18 months, representing the pre-implementation, implementation and the post-implementation phases with comparison to the control CCG and applicable national Quality and Outcomes Framework and national prescribing statistics (e.g. OpenPrescribing). Secondary outcomes include an equity impact analysis with results stratified by age, gender, ethnic group and index of deprivation.

Preliminary data

We present preliminary data on Key Performance Indicators (KPIs) collected from 191 GP practices including [percentage achievement on 01/09/2019, on 01/09/2020]: 1. Patients with hypertension and most recent blood pressure ≤140/90mmHg [68.7%, 60.6%]. 2. Patients eligible for treatment with a high-intensity statin on such treatment [53.8%, 55.8%]. 3. Patients on antithrombotics with ≥1 risk factors for gastrointestinal bleeding on gastroprotection [59.0%, 60.1%]. We also present our virtual patient-review software tool and outcome visualisation dashboard.

Conclusion

The REAL-Health Triple Aim initiative is a large-scale primary care cardiovascular risk reduction initiative which was launched almost contemporaneously with the United Kingdom's first SARS-CoV-2 related lockdown. Preliminary data justify the need for the Triple Aim initiative and give us an insight on the impact of the pandemic on its implementation.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Barts CharityBritish Heart Foundation

Intrapatient comparisons of efficacy in a single-arm trial of entrectinib in tumour-agnostic indications

Background

Entrectinib is a tropomyosin receptor kinase inhibitor approved for the treatment of neurotrophic tyrosine receptor kinase (NTRK) fusion-positive solid tumours based on single-arm trials. Traditional randomised clinical trials in rare cancers are not feasible; we conducted an intrapatient analysis to evaluate the clinical benefit of entrectinib versus prior standard-of-care systemic therapies.

Methods

Patients with locally advanced/metastatic NTRK fusion-positive tumours enrolled in the global phase II, single-arm STARTRK-2 trial were grouped according to prior systemic therapy and response. The key analysis used growth modulation index [GMI; ratio of progression-free survival (PFS) on entrectinib to time to discontinuation (TTD) on the most recent prior therapy]; ratio ≥1.3 indicated clinically meaningful efficacy. Additional analyses investigated TTD and objective response rate (ORR) for entrectinib and prior therapies.

Results

Seventy-one patients were included; 51 received prior systemic therapy. In 38 patients who progressed on prior therapy, ORR was 60.5% (23/38) with entrectinib and 15.8% (6/38) with the most recent prior therapy. Median PFS [11.2 months; 95% confidence interval (CI) 6.7–not estimable] for entrectinib exceeded median TTD (2.9 months; 95% CI 2.0-4.9) for most recent prior therapy. From the intrapatient analysis of GMI, 65.8% had a ratio ≥1.3 and median GMI was 2.53. Consistent results were observed at more stringent GMI thresholds; 60.5% of patients had GMI ≥1.5 or ≥1.8 and 57.9% had GMI ≥2.0.

Conclusions

ORR was high and PFS was longer on entrectinib versus TTD on prior therapy. Furthermore, 65.8% of patients experienced clinically meaningful benefit based on GMI. This intrapatient analysis demonstrates comparative effectiveness of entrectinib in a rare, heterogeneous adult population.

•

Randomised trials are unfeasible for molecular targeted agents in rare indications because of low patient numbers.

•

Intrapatient comparison with prior therapies can be used to evaluate relative treatment efficacy in rare tumours.

•

Entrectinib is a potent tropomyosin receptor kinase (TRK) inhibitor with proven efficacy in neurotrophic tyrosine receptor kinase (NTRK) fusion-positive tumours from the global STARTRK-2 trial.

•

Median progression-free survival on entrectinib was longer than time to discontinuation on prior therapy (11.2 months versus 2.9 months).

•

About 61% of patients with prior therapy progression responded to entrectinib; 66% had growth modulation index ≥1.3 (clinically meaningful threshold).

Suitability of Text-Based Communications for the Delivery of Psychological Therapeutic Services to Rural and Remote Communities: Scoping Review

BACKGROUND

People living in rural and remote areas have poorer access to mental health services than those living in cities. They are also less likely to seek help because of self-stigma and entrenched stoic beliefs about help seeking as a sign of weakness. E-mental health services can span great distances to reach those in need and offer a degree of privacy and anonymity exceeding that of traditional face-to-face counseling and open up possibilities for identifying at-risk individuals for targeted intervention.

OBJECTIVE

This scoping review maps the research that has explored text-based e-mental health counseling services and studies that have used language use patterns to predict mental health status. In doing so, one of the aims was to determine whether text-based counseling services have the potential to circumvent the barriers faced by clients in rural and remote communities using technology and whether text-based communications, in particular, can be used to identify individuals at risk of psychological distress or self-harm.

METHODS

We conducted a comprehensive electronic literature search of PsycINFO, PubMed, ERIC, and Web of Science databases for articles published in English through November 2020.

RESULTS

Of the 9134 articles screened, 70 met the eligibility criteria and were included in the review. There is preliminary evidence to suggest that text-based, real-time communication with a qualified therapist is an effective form of e-mental health service delivery, particularly for individuals concerned with stigma and confidentiality. There is also converging evidence that text-based communications that have been analyzed using computational linguistic techniques can be used to accurately predict progress during treatment and identify individuals at risk of serious mental health conditions and suicide.

CONCLUSIONS

This review reveals a clear need for intensified research into the extent to which text-based counseling (and predictive models using modern computational linguistics tools) may help deliver mental health treatments to underserved groups such as regional communities, identify at-risk individuals for targeted intervention, and predict progress during treatment. Such approaches have implications for policy development to improve intervention accessibility in at-risk and underserved populations.

Babies detect when the timing is right: Evidence from event-related potentials to a contingent mother-infant conversation

Social interactions are vital for healthy brain development. Burgeoning behavioural evidence indicates that a caregiver who provides contingently timed vocal responses to infant vocalisations provides key support for early language development. Understanding how contingently timed vocal responses relate to neurodevelopment in early infancy is lacking. This study compares event-related potentials (ERPs) to contingent and non-contingently timed vocalisations in 6- and 9-month-old infants (n = 36), and adults (n = 24). ERPs were recorded from each age group while listening to a naturalistic 21-minute recording of a mother playing and conversing with her baby. At 6-months, infants showed a significant positive ERP response to contingent vocalisations by the mother and infant. At 9-months infants showed negative ERP response to the mother's contingent speech. Adults showed no differences in ERPs between contingent and non-contingent speech regardless of the talker. We interpret the increased positivity in response to contingent speech as suggesting that infants show an attentional response at 6-months, and the increased negativity at 9-months relates to lexical-semantic processing. Further work is necessary to confirm the development of distinct ERPs shown in response to natural speech.

Biomarker-guided trials: Challenges in practice

Biomarker-guided trials have drawn considerable attention as they promise to lead to improvements in the benefit-risk ratio of treatments and enhanced opportunities for drug development. A variety of such designs have been proposed in the literature, many of which have been adopted in practice. Implementing such trial designs in practice can be challenging, and identifying those challenges was the main objective of a workshop organised by the MRC Hubs for Trials Methodology Research Network's Stratified Medicine Working Group in March 2017. Participants reflected on completed and ongoing biomarker-guided trials to identify the practical challenges encountered. Here, the key challenges identified during the workshop including those related to funding, ethical and regulatory issues, recruitment, monitoring of samples and laboratories, biomarker assessment, and data sharing and resources, are discussed. Despite the complexities often associated with biomarker-guided trials, the workshop concluded that they can play an important role in advancing the field of personalised medicine. Therefore, it is important that the practical challenges surrounding their implementation are acknowledged and addressed.

Language Training Leads to Global Cognitive Improvement in Older Adults: A Preliminary Study

Purpose We report a preliminary study that prospectively tests the potential cognitive enhancing effect of foreign language (FL) learning in older adults with no clear signs of cognitive decline beyond what is age typical. Because language learning engages a large brain network that overlaps with the network of cognitive aging, we hypothesized that learning a new language later in life would be beneficial. Method Older adults were randomly assigned to 3 training groups: FL, games, and music appreciation. All were trained predominately by a computer-based program for 6 months, and their cognitive abilities were tested before, immediately after, and 3 months after training. Results FL and games, but not music appreciation, improved overall cognitive abilities that were maintained at 3 months after training. Conclusion This is the 1st randomized control study providing preliminary support for the cognitive benefits of FL learning.

Human Click-Based Echolocation of Distance: Superfine Acuity and Dynamic Clicking Behaviour

Some people who are blind have trained themselves in echolocation using mouth clicks. Here, we provide the first report of psychophysical and clicking data during echolocation of distance from a group of 8 blind people with experience in mouth click-based echolocation (daily use for > 3 years). We found that experienced echolocators can detect changes in distance of 3 cm at a reference distance of 50 cm, and a change of 7 cm at a reference distance of 150 cm, regardless of object size (i.e. 28.5 cm vs. 80 cm diameter disk). Participants made mouth clicks that were more intense and they made more clicks for weaker reflectors (i.e. same object at farther distance, or smaller object at same distance), but number and intensity of clicks were adjusted independently from one another. The acuity we found is better than previous estimates based on samples of sighted participants without experience in echolocation or individual experienced participants (i.e. single blind echolocators tested) and highlights adaptation of the perceptual system in blind human echolocators. Further, the dynamic adaptive clicking behaviour we observed suggests that number and intensity of emissions serve separate functions to increase SNR. The data may serve as an inspiration for low-cost (i.e. non-array based) artificial ‘cognitive’ sonar and radar systems, i.e. signal design, adaptive pulse repetition rate and intensity. It will also be useful for instruction and guidance for new users of echolocation.

Human echolocators adjust loudness and number of clicks for detection of reflectors at various azimuth angles

In bats it has been shown that they adjust their emissions to situational demands. Here we report similar findings for human echolocation. We asked eight blind expert echolocators to detect reflectors positioned at various azimuth angles. The same 17.5 cm diameter circular reflector placed at 100 cm distance at 0°, 45° or 90° with respect to straight ahead was detected with 100% accuracy, but performance dropped to approximately 80% when it was placed at 135° (i.e. somewhat behind) and to chance levels (50%) when placed at 180° (i.e. right behind). This can be explained based on poorer target ensonification owing to the beam pattern of human mouth clicks. Importantly, analyses of sound recordings show that echolocators increased loudness and numbers of clicks for reflectors at farther angles. Echolocators were able to reliably detect reflectors when level differences between echo and emission were as low as -27 dB, which is much lower than expected based on previous work. Increasing intensity and numbers of clicks improves signal-to-noise ratio and in this way compensates for weaker target reflections. Our results are, to our knowledge, the first to show that human echolocation experts adjust their emissions to improve sensory sampling. An implication from our findings is that human echolocators accumulate information from multiple samples.

What Can Lexical Tone Training Studies in Adults Tell Us about Tone Processing in Children?

A growing number of studies on the acquisition of lexical tone by adult learners have revealed that factors such as language background, musical experience, cognitive abilities, and neuroanatomy all play a role in determining tone learning success. On the basis of these findings, it has been argued that the effectiveness of tone learning in adulthood depends on individual differences in these factors. However, it is not clear whether similar individual differences play an analogous role in tone learning in childhood. Indeed, relatively few studies have made comparisons between how adults and children learn lexical tones. Here, we review recent developments for tone learning in both adults and children. The review covers tone training in a range of contexts, including in naive listeners, in native speakers of other tone languages, in listeners with varying levels of musical experience, and in individuals with speech and hearing disorders. Finally, we discuss the parallels between adult and child tone learning, and provide recommendations concerning how findings in adult tone training can provide insights into tone learning for children by accommodating the needs of individual learners.

Uncovering the Mechanisms Responsible for Why Language Learning May Promote Healthy Cognitive Aging

One of the great challenges facing humankind in the 21st century is preserving healthy brain function in our aging population. Individuals over 60 are the fastest growing age group in the world, and by 2050, it is estimated that the number of people over the age of 60 will triple. The typical aging process involves cognitive decline related to brain atrophy, especially in frontal brain areas and regions that subserve declarative memory, loss of synaptic connections, and the emergence of neuropathological symptoms associated with dementia. The disease-state of this age-related cognitive decline is Alzheimer's disease and other dementias, which may cause older adults to lose their independence and rely on others to live safely, burdening family members and health care systems in the process. However, there are two lines of research that offer hope to those seeking to promote healthy cognitive aging. First, it has been observed that lifestyle variables such as cognitive leisure activities can moderate the risk of Alzheimer's disease, which has led to the development of plasticity-based interventions for older adults designed to protect against the adverse effects of cognitive decline. Second, there is evidence that lifelong bilingualism acts as a safeguard in preserving healthy brain function, possibly delaying the incidence of dementia by several years. In previous work, we have suggested that foreign language learning programs aimed at older populations are an optimal solution for building cognitive reserve because language learning engages an extensive brain network that is known to overlap with the regions negatively affected by the aging process. Here, we will outline potential future lines of research that may uncover the mechanism responsible for the emergence of language learning related brain advantages, such as language typology, bi- vs. multi-lingualism, age of acquisition, and the elements that are likely to result in the largest gains.

Neural Correlates of Indicators of Sound Change in Cantonese: Evidence from Cortical and Subcortical Processes

Across time, languages undergo changes in phonetic, syntactic, and semantic dimensions. Social, cognitive, and cultural factors contribute to sound change, a phenomenon in which the phonetics of a language undergo changes over time. Individuals who misperceive and produce speech in a slightly divergent manner (called innovators) contribute to variability in the society, eventually leading to sound change. However, the cause of variability in these individuals is still unknown. In this study, we examined whether such misperceptions are represented in neural processes of the auditory system. We investigated behavioral, subcortical (via FFR), and cortical (via P300) manifestations of sound change processing in Cantonese, a Chinese language in which several lexical tones are merging. Across the merging categories, we observed a similar gradation of speech perception abilities in both behavior and the brain (subcortical and cortical processes). Further, we also found that behavioral evidence of tone merging correlated with subjects' encoding at the subcortical and cortical levels. These findings indicate that tone-merger categories, that are indicators of sound change in Cantonese, are represented neurophysiologically with high fidelity. Using our results, we speculate that innovators encode speech in a slightly deviant neurophysiological manner, and thus produce speech divergently that eventually spreads across the community and contributes to sound change.

Complexity, Training Paradigm Design, and the Contribution of Memory Subsystems to Grammar Learning

Although there is variability in nonnative grammar learning outcomes, the contributions of training paradigm design and memory subsystems are not well understood. To examine this, we presented learners with an artificial grammar that formed words via simple and complex morphophonological rules. Across three experiments, we manipulated training paradigm design and measured subjects' declarative, procedural, and working memory subsystems. Experiment 1 demonstrated that passive, exposure-based training boosted learning of both simple and complex grammatical rules, relative to no training. Additionally, procedural memory correlated with simple rule learning, whereas declarative memory correlated with complex rule learning. Experiment 2 showed that presenting corrective feedback during the test phase did not improve learning. Experiment 3 revealed that structuring the order of training so that subjects are first exposed to the simple rule and then the complex improved learning. The cumulative findings shed light on the contributions of grammatical complexity, training paradigm design, and domain-general memory subsystems in determining grammar learning success.

Varying irrelevant phonetic features hinders learning of the feature being trained

Learning to distinguish nonnative words that differ in a critical phonetic feature can be difficult. Speech training studies typically employ methods that explicitly direct the learner's attention to the relevant nonnative feature to be learned. However, studies on vision have demonstrated that perceptual learning may occur implicitly, by exposing learners to stimulus features, even if they are irrelevant to the task, and it has recently been suggested that this task-irrelevant perceptual learning framework also applies to speech. In this study, subjects took part in a seven-day training regimen to learn to distinguish one of two nonnative features, namely, voice onset time or lexical tone, using explicit training methods consistent with most speech training studies. Critically, half of the subjects were exposed to stimuli that varied not only in the relevant feature, but in the irrelevant feature as well. The results showed that subjects who were trained with stimuli that varied in the relevant feature and held the irrelevant feature constant achieved the best learning outcomes. Varying both features hindered learning and generalization to new stimuli.

Sampling strategies for phlebotomine sand flies (Diptera: Psychodidae) in Europe

The distribution of phlebotomine sand flies is widely reported to be changing in Europe. This can be attributed to either the discovery of sand flies in areas where they were previously overlooked (generally following an outbreak of leishmaniasis or other sand fly-related disease) or to true expansion of their range as a result of climatic or environmental changes. Routine surveillance for phlebotomines in Europe is localized, and often one of the challenges for entomologists working in non-leishmaniasis endemic countries is the lack of knowledge on how to conduct, plan and execute sampling for phlebotomines, or how to adapt on-going sampling strategies for other haematophagous diptera. This review brings together published and unpublished expert knowledge on sampling strategies for European phlebotomines of public health concern in order to provide practical advice on: how to conduct surveys; the collection and interpretation of field data; suitable techniques for the preservation of specimens obtained by different sampling methods; molecular techniques used for species identification; and the pathogens associated with sand flies and their detection methods.

Poor phonetic perceivers are affected by cognitive load when resolving talker variability

Speech training paradigms aim to maximise learning outcomes by manipulating external factors such as talker variability. However, not all individuals may benefit from such manipulations because subject-external factors interact with subject-internal ones (e.g., aptitude) to determine speech perception and/or learning success. In a previous tone learning study, high-aptitude individuals benefitted from talker variability, whereas low-aptitude individuals were impaired. Because increases in cognitive load have been shown to hinder speech perception in mixed-talker conditions, it has been proposed that resolving talker variability requires cognitive resources. This proposal leads to the hypothesis that low-aptitude individuals do not use their cognitive resources as efficiently as those with high aptitude. Here, high- and low-aptitude subjects identified pitch contours spoken by multiple talkers under high and low cognitive load conditions established by a secondary task. While high-aptitude listeners outperformed low-aptitude listeners across load conditions, only low-aptitude listeners were impaired by increased cognitive load. The findings suggest that low-aptitude listeners either have fewer available cognitive resources or are poorer at allocating attention to the signal. Therefore, cognitive load is an important factor when considering individual differences in speech perception and training paradigms.

Measurement of lentiviral vector titre and copy number by cross-species duplex quantitative PCR

Lentiviruses are the vectors of choice for many preclinical studies and clinical applications of gene therapy. Accurate measurement of biological vector titre before treatment is a prerequisite for vector dosing, and the calculation of vector integration sites per cell after treatment is as critical to the characterisation of modified cell products as it is to long-term follow-up and the assessment of risk and therapeutic efficiency in patients. These analyses are typically based on quantitative real-time PCR (qPCR), but as yet compromise accuracy and comparability between laboratories and experimental systems, the former by using separate simplex reactions for the detection of endogene and lentiviral sequences and the latter by designing different PCR assays for analyses in human cells and animal disease models. In this study, we validate in human and murine cells a qPCR system for the single-tube assessment of lentiviral vector copy numbers that is suitable for analyses in at least 33 different mammalian species, including human and other primates, mouse, pig, cat and domestic ruminants. The established assay combines the accuracy of single-tube quantitation by duplex qPCR with the convenience of one-off assay optimisation for cross-species analyses and with the direct comparability of lentiviral transduction efficiencies in different species.

The Effect of Intensified Language Exposure on Accommodating Talker Variability

PURPOSE

This study systematically examined the role of intensified exposure to a second language on accommodating talker variability.

METHOD

English native listeners (n = 37) were compared with Mandarin listeners who had either lived in the United States for an extended period of time (n = 33) or had lived only in China (n = 44). Listeners responded to target words in an English word-monitoring task in which sequences of words were randomized. Half of the sequences were spoken by a single talker and the other half by multiple talkers.

RESULTS

Mandarin listeners living in China were slower and less accurate than both English listeners and Mandarin listeners living in the United States. Mandarin listeners living in the United States were less accurate than English natives only in the more cognitively demanding mixed-talker condition.

CONCLUSIONS

Mixed-talker speech affects processing in native and nonnative listeners alike, although the decrement is larger in nonnatives and further exaggerated in less proficient listeners. Language immersion improves listeners' ability to resolve talker variability, and this suggests that immersion may automatize nonnative processing, freeing cognitive resources that may play a crucial role in speech perception. These results lend support to the active control model of speech perception.

Systemic gene transfer of binding immunoglobulin protein (BiP) prevents disease progression in murine collagen-induced arthritis

Summary Recombinant human binding immunoglobulin protein (BiP) has previously demonstrated anti-inflammatory properties in multiple models of inflammatory arthritis. We investigated whether these immunoregulatory properties could be exploited using gene therapy techniques. A single intraperitoneal injection of lentiviral vector containing the murine BiP (Lenti-mBiP) or green fluorescent protein (Lenti-GFP) transgene was administered in low- or high-dose studies during early arthritis. Disease activity was assessed by visual scoring, histology, serum cytokine and antibody production measured by cell enzyme-linked immunosorbent assay (ELISA) and ELISA, respectively. Lentiviral vector treatment caused significant induction of interferon (IFN)-γ responses regardless of the transgene; however, further specific effects were directly attributable to the BiP transgene. In both studies Lenti-mBiP suppressed clinical arthritis significantly. Histological examination showed that low-dose Lenti-mBiP suppressed inflammatory cell infiltration, cartilage destruction and significantly reduced pathogenic anti-type II collagen (CII) antibodies. Lenti-mBiP treatment caused significant up-regulation of soluble cytotoxic T lymphocyte antigen-4 (sCTLA-4) serum levels and down-regulation of interleukin (IL)-17A production in response to CII cell restimulation. In-vitro studies confirmed that Lenti-mBiP spleen cells could significantly suppress the release of IL-17A from CII primed responder cells following CII restimulation in vitro, and this suppression was associated with increased IL-10 production. Neutralization of CTLA-4 in further co-culture experiments demonstrated inverse regulation of IL-17A production. In conclusion, these data demonstrate proof of principle for the therapeutic potential of systemic lentiviral vector delivery of the BiP transgene leading to immunoregulation of arthritis by induction of soluble CTLA-4 and suppression of IL-17A production.

Investigating the role of articulatory organs and perceptual assimilation of native and non-native fricative place contrasts

The perceptual assimilation model (PAM; Best, C. T. [1995]. A direct realist view of cross-language speech perception. In W. Strange (Ed.), Speech perception and linguistic experience: Issues in cross-language research (pp. 171-204). Baltimore, MD: York Press.) accounts for developmental patterns of speech contrast discrimination by proposing that infants shift from untuned phonetic perception at 6 months to natively tuned perceptual assimilation at 11-12 months, but the model does not predict initial discrimination differences among contrasts. To address that issue, we evaluated the Articulatory Organ Hypothesis, which posits that consonants produced using different articulatory organs are initially easier to discriminate than those produced with the same articulatory organ. We tested English-learning 6- and 11-month-olds' discrimination of voiceless fricative place contrasts from Nuu-Chah-Nulth (non-native) and English (native), with one within-organ and one between-organ contrast from each language. Both native and non-native contrasts were discriminated across age, suggesting that articulatory-organ differences do not influence perception of speech contrasts by young infants. The results highlight the fact that a decline in discrimination for non-native contrasts does not always occur over age.

The role of indigenous phlebotomine sandflies and mammals in the spreading of leishmaniasis agents in the Mediterranean region

An updated view of the establishment and spread of the leishmaniases in Europe is presented, mostly with respect to newly emerging and re-emerging foci and the incrimination of neglected as well as new reservoir hosts. At the same time, a concept of specific versus permissive vectors reassesses the potential role of various sandfly species in Leishmania transmission and considers the risk of introduction of exotic Leishmania species in Europe. The leishmaniases are dynamic diseases and the circumstances of transmission are continually changing in relation to environmental, demographic and human behavioural factors. Changes in the habitat of the natural hosts and vectors, immunosuppressive conditions (like infection with human immunodeficiency virus (HIV) or organ transplantation-associated therapies in humans) and the consequences of war, all contribute to the transformation of the epidemiology of leishmaniasis. Such changes should be considered when studying the spread of the disease throughout Europe for targeted control measures to safeguard public health.

Focusing the lens of language experience: perception of Ma'di stops by Greek and English bilinguals and monolinguals

Monolingual listeners are constrained by native language experience when categorizing and discriminating unfamiliar non-native contrasts. Are early bilinguals constrained in the same way by their two languages, or do they possess an advantage? Greek-English bilinguals in either Greek or English language mode were compared to monolinguals on categorization and discrimination of Ma'di stop-voicing distinctions that are non-native to both languages. As predicted, English monolinguals categorized Ma'di prevoiced plosive and implosive stops and the coronal voiceless stop as English voiced stops. The Greek monolinguals categorized the Ma'di short-lag voiceless stops as Greek voiceless stops, and the prevoiced implosive stops and the coronal prevoiced stop as Greek voiced stops. Ma'di prenasalized stops were uncategorized. Greek monolinguals discriminated the non-native voiced-voiceless contrasts very well, whereas the English monolinguals did poorly. Bilinguals were given all oral and written instructions either in English or in Greek (language mode manipulation). Each language mode subgroup categorized Ma'di stop-voicing comparably to the corresponding monolingual group. However, the bilinguals' discrimination was unaffected by language mode: both subgroups performed intermediate to the monolinguals for the prevoiced-voiceless contrast. Thus, bilinguals do not possess an advantage for unfamiliar non-native contrasts, but are nonetheless uniquely configured language users, differing from either monolingual group.

Two ways to listen: Do L2-dominant bilinguals perceive stop voicing according to language mode?

How listeners categorize two phones predicts the success with which they will discriminate the given phonetic distinction. In the case of bilinguals, such perceptual patterns could reveal whether the listener's two phonological systems are integrated or separate. This is of particular interest when a given contrast is realized differently in each language, as is the case with Greek and English stop-voicing distinctions. We had Greek-English early sequential bilinguals and Greek and English monolinguals (baselines) categorize, rate, and discriminate stop-voicing contrasts in each language. All communication with each group of bilinguals occurred solely in one language mode, Greek or English. The monolingual groups showed the expected native-language constraints, each perceiving their native contrast more accurately than the opposing nonnative contrast. Bilinguals' category-goodness ratings for the same physical stimuli differed, consistent with their language mode, yet their discrimination performance was unaffected by language mode and biased toward their dominant language (English). We conclude that bilinguals integrate both languages in a common phonetic space that is swayed by their long-term dominant language environment for discrimination, but that they selectively attend to language-specific phonetic information for phonologically motivated judgments (category-goodness ratings).

Inter-language interference in VOT production by L2-dominant bilinguals: Asymmetries in phonetic code-switching

Speech production research has demonstrated that the first language (L1) often interferes with production in bilinguals' second language (L2), but it has been suggested that bilinguals who are L2-dominant are the most likely to suppress this L1-interference. While prolonged contextual changes in bilinguals' language use (e.g., stays overseas) are known to result in L1 and L2 phonetic shifts, code-switching provides the unique opportunity of observing the immediate phonetic effects of L1-L2 interaction. We measured the voice onset times (VOTs) of Greek-English bilinguals' productions of /b, d, p, t/ in initial and medial contexts, first in either a Greek or English unilingual mode, and in a later session when they produced the same target pseudowords as a code-switch from the opposing language. Compared to a unilingual mode, all English stops produced as code-switches from Greek, regardless of context, had more Greek-like VOTs. In contrast, Greek stops showed no shift toward English VOTs, with the exception of medial voiced stops. Under the specifically interlanguage condition of code-switching we have demonstrated a pervasive influence of the L1 even in L2-dominant individuals.

Language context elicits native-like stop voicing in early bilinguals' productions in both L1 and L2

The way that bilinguals produce phones in each of their languages provides a window into the nature of the bilingual phonological space. For stop consonants, if early sequential bilinguals, whose languages differ in voice onset time (VOT) distinctions, produce native-like VOTs in each of their languages, it would imply that they have developed separate first and second language phones, that is, language-specific phonetic realisations for stop-voicing distinctions. Given the ambiguous phonological status of Greek voiced stops, which has been debated but not investigated experimentally, Greek-English bilinguals can offer a unique perspective on this issue. We first recorded the speech of Greek and Australian-English monolinguals to observe native VOTs in each language for /p, t, b, d/ in word-initial and word-medial (post-vocalic and post-nasal) positions. We then recorded fluent, early Greek-Australian-English bilinguals in either a Greek or English language context; all communication occurred in only one language. The bilinguals in the Greek context were indistinguishable from the Greek monolinguals, whereas the bilinguals in the English context matched the VOTs of the Australian-English monolinguals in initial position, but showed some modest differences from them in the phonetically more complex medial positions. We interpret these results as evidence that bilingual speakers possess phonetic categories for voiced versus voiceless stops that are specific to each language, but are influenced by positional context differently in their second than in their first language.

Leishmania donovani s.l.: evaluation of the proliferation potential of promastigotes using CFSE staining and flow cytometry

Leishmania infantum causes visceral leishmaniasis in all countries in the Mediterranean basin. It uses Phlebotomine sandflies as vectors where the promastigote stage develops, reproduces and becomes infective. Therefore the reproductive power of the promastigotes determines the inoculum size of the isolate. Ten Leishmania strains from Cyprus: two Leishmania donovani and eight L. infantum were used to study the proliferation capacity of the promastigotes. Population increase during a 6-day culture period was assessed quantitatively, by haematocytometer enumeration, and qualitatively by following the division history of each population during the same period by CFSE staining and flow cytometry. The strains exhibited different proliferation rates with L. infantum showing higher multiplication rates than L. donovani. These differences may represent their fitness capabilities and their ability to synchronize the multiplication activity of individual members in the population for the production of a sizeable inoculum in time for the vector's blood meal.