Native Signers Research Articles

Theory of Mind (ToM) Development in Thai Deaf Children.

This study explored theory of mind (ToM) development in school-aged deaf children. To address new questions, we gave a standard, well-controlled false-belief test to a large (n = 200) sample of severely-to-profoundly deaf children aged 8-15years in a non-Western culture (Thailand). There were 190 deaf children of hearing parents and 10 deaf native signers with signing deaf parents, consistent with overall population ratios. Comparing our Thai sample's ToM performance on standard tests of false-belief understanding with that reported in past studies, our results showed a 67% ToM success rate for Thai severely-to-profoundly deaf children of hearing parents similar to collective findings from past research on smaller samples in Australia, Estonia, France, Great Britain, Sweden, and the United States. Our Thai deaf native signers likewise performed equivalently to native signers of similar age studied in past research in Australia and the United States. Collectively, the detailed findings of our study suggest promising new directions for future studies to pursue in order to build upon this novel and theoretically provocative evidence about how ToM development and ToM delay unfold for school-aged deaf children growing up in varied cultures, school settings, and family circumstances.

The interaction of the visuo-spatial and the vestibular system depends on sensory experience in development

In hearing individuals, vestibular and visuo-spatial functions seem to be functionally linked. Previous studies have suggested that congenitally deaf individuals are at a higher risk for vestibular problems, which in hearing adults have often been found to be associated with impairments in visuo-spatial processing. However, communicating in a sign language provides extensive practice in visuo-spatial processing, which might counteract negative effects of vestibular impairments. Here, we investigated whether the functional link between vestibular and visuo-spatial functions is mandatory, that is whether it is impenetrable to experience or context, or whether it is dependent on specific sensory and cognitive experiences. To this end, we tested a group of congenitally deaf native signers and a group of hearing nonsigners on mental rotation and balance tasks. Compared to hearing nonsigners, mental rotation was superior in the deaf signers in conditions crucial for sign language comprehension. By contrast, the balance performance of the group of deaf signers was impaired. While in the group of hearing nonsigners, balance skills correlated with mental rotation abilities, no such relationship was observed in the group of deaf signers. These results suggest that the link between vestibular and visuo-spatial functions is not fixed but can be altered or even cancelled out by certain sensory or cognitive experiences, such as the acquisition of a sign language.

Reading skills of D/deaf students – native signers

Reading skills of D/deaf students fall behind their hearing peers. The difference in reading skills between D/deaf and hearing children has not decreased for over past three decades. Low level of reading skills in D/deaf students has been associated with their language delay, which is mainly observed in D/deaf children using spoken language that is not fully accessible to “D/deaf individuals” instead of “ppl with hearing impairment”. D/deaf children immersed in sign language since their birth usually do not encounter language problems and they have a potential to become highly-skilled readers. In the present studies we have investigated reading skills of D/deaf students who are native signers of Polish Sign Language. The results have indicated that D/deaf students showed lower level of reading skills than their hearing peers. The present studies call in question Polish education system dedicated to D/deaf students who are native signers. The obtained results suggest that reading classes are probably not adapted to the needs and abilities of highly competent signers.

Effects of deafness and sign language experience on the human brain: voxel-based and surface-based morphometry

ABSTRACT We investigated how deafness and sign language experience affect the human brain by comparing neuroanatomical structures across congenitally deaf signers (n = 30), hearing native signers (n = 30), and hearing sign-naïve controls (n = 30). Both voxel-based and surface-based morphometry results revealed deafness-related structural changes in visual cortices (grey matter), right frontal lobe (gyrification), and left Heschl's gyrus (white matter). The comparisons also revealed changes associated with lifelong signing experience: expansions in the surface area within left anterior temporal and left occipital lobes, and a reduction in cortical thickness in the right occipital lobe for deaf and hearing signers. Structural changes within these brain regions may be related to adaptations in the neural networks involved in processing signed language (e.g. visual perception of face and body movements). Hearing native signers also had unique neuroanatomical changes (e.g. reduced gyrification in premotor areas), perhaps due to lifelong experience with both a spoken and a signed language.

Evolution of the Doctrine of Signatures of Things and the Adamic Language in the Chemical Philosophy of the 16th and 17th Centuries

The aim of the paper is to investigate paths along which a transformation of the doctrine of natural signs was developed in works by Paracelsians, forming one of the main religious and philosophic currents of Late Renaissance. The modifications of the doctrine are discussed in a context of intensive speculations on the essence of the primordial language of humankind and on the possibility of its restoration, which can describe the intellectual life of that epoch. It is argued that within “chemical philosophy” the possibility of restoration of the Adamic language directly depends on mastering the art of interpreting natural signs (signatura rerum), which can give a key to correct understanding of nature. And shifts in the conceptualization of such signatures involved transformations in formulating and solving of the Adamistic problems, which did not exclude reverse causation. It is also ascertained that the most orthodox followers of Paracelsus usually appealed to the Adamistic narrative in order to reinforce legitimacy of the symbolic hermeneutics of nature, developed with chiefly medico-pharmacological purposes. Meanwhile, relatively more independent Paracelsians often paid more attention to linguo-philosophic issues. Realizing the deficiency of the doctrine of signatures for reconstruction of the primordial language, they postulated the necessity of one (or two) of the following premises: (a) supplementing the doctrine with a mystical illumination; (b) acceptance of a weaker version, according to which natural signs are just sparse reference points slightly simplifying empirical study of nature; (c) abandonment of search for the Ursprache and constructing its artificial substitute, a universal semiotic system.

Effects of ASL Rhyme and Rhythm on Deaf Children's Engagement Behavior and Accuracy in Recitation: Evidence from a Single Case Design.

Early language acquisition is critical for lifelong success in language, literacy, and academic studies. There is much to explore about the specific techniques used to foster deaf children’s language development. The use of rhyme and rhythm in American Sign Language (ASL) remains understudied. This single-subject study compared the effects of rhyming and non-rhyming ASL stories on the engagement behavior and accuracy in recitation of five deaf children between three and six years old in an ASL/English bilingual early childhood classroom. With the application of alternating treatment design with initial baseline, it is the first experimental research of its kind on ASL rhyme and rhythm. Baseline data revealed the lack of rhyme awareness in children and informed the decision to provide intervention as a condition to examine the effects of explicit handshape rhyme awareness instruction on increasing engagement behavior and accuracy in recitation. There were four phases in this study: baseline, handshape rhyme awareness intervention, alternating treatments, and preference. Visual analysis and total mean and mean difference procedures were employed to analyze results. The findings indicate that recitation skills in young deaf children can be supported through interventions utilizing ASL rhyme and rhythm supplemented with ASL phonological awareness activities. A potential case of sign language impairment was identified in a native signer, creating a new line of inquiry in using ASL rhyme, rhythm, and phonological awareness to detect atypical language patterns.

Fill the gap: A novel test to elicit nominal plurals in Sign Language of the Netherlands

The present study introduces a novel gap-filling test to elicit plural nouns in Sign Language of the Netherlands (NGT). As of yet, nominal plurals in NGT have not been described in detail, as eliciting plural nouns is not without challenges. In previous research on NGT (Zwitserlood and Nijhof 1999), native signers were asked to describe pictures of plural objects. However, when describing pictures, the signers automatically also expressed the spatial distribution of the objects depicted on the stimulus picture, using localization. As a consequence, it remains unclear what ‘pure’ plurals – without localization – look like. The goal of our gap-filling task is to disentangle pluralization from localization: participants are asked to insert plural nouns in signed sentence contexts where the spatial distribution of the referents is irrelevant. After piloting the task, five deaf native signers participated. The task succeeded in eliciting pure plural forms that were not spatially distributed, and the results show that NGT optionally employs reduplication to mark the pure plural of nouns. We conclude that our gap-filling task successfully controls for localization, targeting the desired structure without using written language. In future studies, the gap-filling task can be applied to other sign languages, targeting also other construction types.

Effects and Non-Effects of Late Language Exposure on Spatial Language Development: Evidence from Deaf Adults and Children

ABSTRACT Late exposure to the first language, as in the case of deaf children with hearing parents, hinders the production of linguistic expressions, even in adulthood. Less is known about the development of language soon after language exposure and if late exposure hinders all domains of language in children and adults. We compared late signing adults and children (MAge = 8;5) 2 years after exposure to sign language, to their age-matched native signing peers in expressions of two types of locative relations that are acquired in certain cognitive-developmental order: view-independent (IN-ON-UNDER) and view-dependent (LEFT-RIGHT). Late signing children and adults differed from native signers in their use of linguistic devices for view-dependent relations but not for view-independent relations. These effects were also modulated by the morphological complexity. Hindering effects of late language exposure on the development of language in children and adults are not absolute but are modulated by cognitive and linguistic complexity.

Space Oddities: The Acquisition of Agreement Verbs by L2 Learners of Sign Language of the Netherlands

AbstractThis article reports the results of the first longitudinal study that systematically investigates the acquisition of verb agreement by hearing learners of a sign language. During a 2‐year period, 14 novel learners of Sign Language of the Netherlands (NGT) with a spoken language background performed an elicitation task 15 times. Seven deaf native signers and NGT teachers performed the same task to serve as a benchmark group. The results obtained show that for some learners, the verb agreement system of NGT was difficult to master, despite numerous examples in the input. As compared to the benchmark group, learners tended to omit agreement markers on verbs that could be modified, did not always correctly use established locations associated with discourse referents, and made characteristic errors with respect to properties that are important in the expression of agreement (movement and orientation). The outcomes of the study are of value to practitioners in the field, as they are informative with regard to the nature of the learning process during the first stages of learning a sign language.

Language experience in LSF development: Behavioral evidence from a sentence repetition task.

In psycholinguistics and clinical linguistics, the Sentence Repetition Task (SRT) is known to be a valuable tool to screen general language abilities in both spoken and signed languages. This task enables users to reliably and quickly assess linguistic abilities at different levels of linguistic analysis such as phonology, morphology, lexicon, and syntax. To evaluate sign language proficiency in deaf children using French Sign Language (LSF), we designed a new SRT comprising 20 LSF sentences. The task was administered to a cohort of 62 children- 34 native signers (6;09-12 years) and 28 non-native signers (6;08-12;08 years)-in order to study their general linguistic development as a function of age of sign language acquisition (AOA) and chronological age (CA). Previously, a group of 10 adult native signers was also evaluated with this task. As expected, our results showed a significant effect of AOA, indicating that the native signers repeated more signs and were more accurate than non-native signers. A similar pattern of results was found for CA. Furthermore, native signers made fewer phonological errors (i.e., handshape, movement, and location) than non-native signers. Finally, as shown in previous sign language studies, handshape and movement proved to be the most difficult parameters to master regardless of AOA and CA. Taken together, our findings support the assumption that AOA is a crucial factor in the development of phonological skills regardless of language modality (spoken vs. signed). This study thus constitutes a first step toward a theoretical description of the developmental trajectory in LSF, a hitherto understudied language.

A Developmental Disorder of Signed Language Production in a Native Deaf Signer of ASL

Evidence for a Developmental Language Disorder (DLD) could surface with language processing/comprehension, language production, or a combination of both. Whereas, various studies have described cases of DLD in signing deaf children, there exist few detailed examples of deaf children who exhibit production issues in the absence of processing or comprehension challenges or motor deficits. We describe such a situation by detailing a case study of “Gregory”, a deaf native signer of American Sign Language (ASL). We adopt a detailed case-study methodology for obtaining information from Gregory’s family and school, which we combine with linguistic and non-linguistic data that we collected through one-on-one sessions with Gregory. The results provide evidence of persistent issues with language production (in particular, atypical articulation of some phonological aspects of signs), yet typical comprehension skills and unremarkable fine-motor motor skills. We also provide a snapshot of Gregory’s rich linguistic environment, which we speculate, may serve to attenuate his production deficit. The results of this study have implications for the provision of language services for signing deaf children in schools and also for language therapists. We propose that language therapists who are fluent in signed language be trained to work with signing children.

Assessing Vocabulary in Deaf and Hearing Children using Finnish Sign Language.

This study investigates children's vocabulary knowledge in Finnish Sign Language (FinSL), specifically their understanding of different form-meaning mappings by using a multilayered assessment format originally developed for British Sign Language (BSL). The web-based BSL vocabulary test by Mann (2009) was adapted for FinSL following the steps outlined by Mann, Roy and Morgan (2016) and piloted with a small group of deaf and hearing native signers (N = 24). Findings showed a hierarchy of difficulty between the tasks, which is concordant with results reported previously for BSL and American Sign Language (ASL). Additionally, the reported psychometric properties of the FinSL vocabulary test strengthen previous claims made for BSL and ASL that the underlying construct is appropriate for use with signed languages. Results also add new insights into the adaptation process of tests from one signed language to another and show this process to be a reliable and valid way to develop assessment tools in lesser-researched signed languages such as FinSL.

Acquisition of Sign Languages.

Natural sign languages of deaf communities are acquired on the same time scale as that of spoken languages if children have access to fluent signers providing input from birth. Infants are sensitive to linguistic information provided visually, and early milestones show many parallels. The modality may affect various areas of language acquisition; such effects include the form of signs (sign phonology), the potential advantage presented by visual iconicity, and the use of spatial locations to represent referents, locations, and movement events. Unfortunately, the vast majority of deaf children do not receive accessible linguistic input in infancy, and these children experience language deprivation. Negative effects on language are observed when first-language acquisition is delayed. For those who eventually begin to learn a sign language, earlier input is associated with better language and academic outcomes. Further research is especially needed with a broader diversity of participants.

Applicability of impulse excitation technique as a tool to characterize the elastic properties of pharmaceutical tablets: Experimental and numerical study.

Elastic properties are of particular interest during the development of tablets especially for the definition of the formulation and of the process parameters. Impulse excitation, which is used in several industrial fields to determine elastic properties of materials, is presented in this article as a new fast and relatively cheap technology for the determination of elastic constants of pharmaceutical tablets. This technique is based on the detection of the natural resonance frequencies of solids. It was found in the present work that, for tablets obtained using different products under different compaction pressures, it was possible to detect clearly at least 3 resonance frequencies. Moreover, the shape of the resonance peaks obtained in the spectrum could be a sign of the viscoelastic nature of the tablet. With the two first resonance frequencies, it was possible, under the assumption of isotropy, to calculate Young's modulus and Poisson's ratio for each tablet using the methodology presented in the norm ASTM E1876-01. The values obtained were found independent of the tablet size as expected, and were consistent with those presented in the literature using other methodologies. Moreover, using FEM simulation, it was found that the difference between the experimental value of the third resonance frequency and the value obtained numerically was well correlated with the expected anisotropy of the tablet. Impulse excitation could thus be an interesting methodology to study tablet anisotropy.

Bilingual school education with spoken and signed languages in Europe

ABSTRACT At least since the UN Convention on the Rights of People with Disabilities, deaf children worldwide have a right to education not only in the spoken and written language of their country, but also in the national sign language. The pedagogical use of a sign language in European schools for the deaf began in the 1980s and has since evolved significantly. This paper presents a survey of 39 European countries that documents the status of bimodal bilingual education using a spoken and a signed language. Data was collected through an expert survey on the three dimensions policies, practices and cultures of bimodal bilingual education and an analysis of relevant legal documents. The results reveal that bimodal bilingual education is increasingly implemented in deaf education but is not fully established all over Europe. In many countries, bimodal bilingual education is limited to special schools and is rarely offered in inclusive mainstream schools. Implementation processes are similar across Europe: Programmes are primarily initiated by parents, teachers or the deaf community but educational policies lag behind the practices at schools. Legal foundations (e.g. curricula and professionalization for the use of sign languages) guarantee the sustainability and quality of bimodal bilingual education.

Emerging Developments in Human Induced Pluripotent Stem Cell-Derived Microglia: Implications for Modelling Psychiatric Disorders With a Neurodevelopmental Origin.

Microglia, the resident tissue macrophages of the brain, are increasingly implicated in the pathophysiology of psychiatric disorders with a neurodevelopmental origin, including schizophrenia. To date, however, our understanding of the potential role for these cells in schizophrenia has been informed by studies of aged post-mortem samples, low resolution in vivo neuroimaging and rodent models. Whilst these have provided important insights, including signs of the heterogeneous nature of microglia, we currently lack a validated human in vitro system to characterize microglia in the context of brain health and disease during neurodevelopment. Primarily, this reflects a lack of access to human primary tissue during developmental stages. In this review, we first describe microglia, including their ontogeny and heterogeneity and consider their role in brain development. We then provide an evaluation of the potential for differentiating microglia from human induced pluripotent stem cells (hiPSCs) as a robust in vitro human model system to study these cells. We find the majority of protocols for hiPSC-derived microglia generate cells characteristically similar to foetal stage microglia when exposed to neuronal environment-like cues. This may represent a robust and relevant model for the study of cellular and molecular mechanisms in schizophrenia. Each protocol however, provides unique benefits as well as shortcomings, highlighting the need for context-dependent protocol choice and cross-lab collaboration and communication to identify the most robust and translatable microglia model.

“Sign to me, not the children”: Ideologies of language contamination at a deaf tourist site in Bali

Certain historical processes and sign language ideologies have led to the dissemination of American Sign Language (ASL) signs throughout Southeast Asia via deaf education projects, international development interventions, and tourism, notably in Cambodia and Indonesia. These ideologies normalized attempts to develop standardised sign systems based on national spoken languages and the introduction of signs from foreign sign languages, especially ASL. This history has shaped and mobilized ideas among deaf sign language users about language contact, the spread of hegemonic national sign languages, and the vitality of sign languages outside of the US and western Europe. Some of these ideologies manifest in deaf signers’ concerns about the vitality of what are often perceived to be non-hegemonic sign languages (e.g., sign languages that are not ASL, Auslan, or BSL) and language practices. By examining discourses and practices in the context of encounters between deaf tourists and deaf leaders in Bali, this article approaches larger questions about the territorialization of sign languages, linguistic boundaries, language contact, and sign language vitality.

Second verse, same as the first: On the use of signing systems in modern interventions for deaf and hard of hearing children in the USA

ABSTRACT Signing systems that attempted to represent spoken language via manual signs – some invented, and some borrowed from natural sign languages – have historically been used in classrooms with deaf children. However, despite decades of research and use of these systems in the classroom, there is little evidence supporting their educational effectiveness. In this paper, the authors argue against the use of signing systems as instructional tools. This argument is based upon research demonstrating that (1) signing systems are less comprehensible to learners who rely upon signs rather than speech, (2) signing systems are used inconsistently by teachers, and (3) signing systems often unintentionally exhibit features of natural signed grammar, leading to input that does not accurately convey spoken languages, which is the original intention of these systems. Instead, the authors advocate for a return to the use of natural signed languages in classrooms educating deaf children, with creative uses of interpretation to provide those students who may prefer or benefit from spoken English with its presence in the classroom. In addition, we note ways in which future research may explore how natural sign languages and deaf adults may benefit the educational experiences of deaf children.

Age, frequency, and iconicity in early sign language acquisition: Evidence from the Israeli Sign Language MacArthur–Bates Communicative Developmental Inventory

AbstractThe current study described the development of the MacArthur–Bates Communicative Developmental Inventory (CDI) for Israeli Sign Language (ISL) and investigated the effects of age, sign iconicity, and sign frequency on lexical acquisition of bimodal-bilingual toddlers acquiring ISL. Previous findings bring inconclusive evidence on the role of sign iconicity (the relationship between form and meaning) and sign frequency (how often a word/sign is used in the language) on the acquisition of signs. The ISL-CDI consisted of 563 video clips. Iconicity ratings from 41 sign-naïve Hebrew-speaking adults (Study 1A) and sign frequency ratings from 19 native ISL adult signers (Study 1B) were collected. ISL vocabulary was evaluated in 34 toddlers, native signers (Study 2). Results indicated significant effects of age, strong correlations between parental ISL ratings and ISL size even when age was controlled for, and strong correlations between naturalistic data and ISL-CDI scores, supporting the validity of the ISL-CDI. Moreover, the results revealed effects of iconicity, frequency, and interactions between age and the iconicity and frequency factors, suggesting that both iconicity and frequency are modulated by age. The findings contribute to the field of sign language acquisition and to our understanding of potential factors affecting human language acquisition beyond language modality.

Предмет биологической формы существования.

For millennia, thinking people had to give an explanation of the phenomenon of life, and some tried to formulate a definition of a living creature in which there was not a single body, nor a creature that existed in consciousness or spirit thinking. Thus, the complexity was stable, unsolvable, and as a result, problems arose that arose as a result of the existence of a single organism. Existence in two antagonistic, according to thinkers, forms of existence in being and in thinking. In this regard, the attempt to present the signs of the biological form of existence, which indicate that the transcendental worldview is an object of the living, in which the signs of the existence of a socio-historical nature are distinctly relevant, is relevant signs of a social-historical nature. There are biological forms in which all the necessary objects exist, as well as mutual understanding, mutual understanding, and exchange of views during the evaporation process forms of existence. The fact that the existing in this area of existence is essentially not observable indicates that the transcendental worldview cannot be justified by refuting factors, and therefore does not require evidence that their reliability has not been proved, and not only in the veracity, nor in the veracity of the outlined worldview views, there are quite significant in this area.