One significant area of research in the multifaceted field of bilingualism over the past two decades has been the demonstration, validation, and account of the so-called ‘bilingual advantage’. This refers to the hypothesis that bilingual speakers have advanced abilities in executive functions and other domains of human cognition. Such cognitive benefits of bilingualism have an impact on the processing mechanisms active during language acquisition in a way that results in language variation. Within bilingual populations, the notion of language proximity (or linguistic distance) is also of key importance for deriving variation. In addition, sociolinguistic factors can invest the process of language development and its outcome with an additional layer of complexity, such as schooling, language, dominance, competing motivations, or the emergence of mesolectal varieties, which blur the boundaries of grammatical variants. This is particularly relevant for diglossic speech communities—bilectal, bidialectal, or bivarietal speakers. The defined goal of the present Research Topic is to address whether the bilingual advantage extends to such speakers as well. Thus, ‘Linguistic and Cognitive Profiles for Speakers of Linguistically Proximal Languages and Varieties’ become an important matter within ‘Developmental, Modal, and Pathological Variation’.

One significant area of research in the multifaceted field of bilingualism over the past two decades has been the demonstration, validation, and account of the so-called 'bilingual advantage'. This refers to the hypothesis that bilingual speakers have advanced abilities in executive functions and other domains of human cognition. Such cognitive benefits of bilingualism have an impact on the processing mechanisms active during language acquisition in a way that results in language variation. Within bilingual populations, the notion of language proximity (or linguistic distance) is also of key importance for deriving variation. In addition, sociolinguistic factors can invest the process of language development and its outcome with an additional layer of complexity, such as schooling, language, dominance, competing motivations, or the emergence of mesolectal varieties, which blur the boundaries of grammatical variants. This is particularly relevant for diglossic speech communities--bilectal, bidialectal, or bivarietal speakers. The defined goal of the present Research Topic is to address whether the bilingual advantage extends to such speakers as well. Thus, 'Linguistic and Cognitive Profiles for Speakers of Linguistically Proximal Languages and Varieties' become an important matter within 'Developmental, Modal, and Pathological Variation'.

The language experience of children developing in linguistically diverse environments is subject to considerable variation both in terms of quantity and quality of language exposure. It is an open question how to investigate language exposure patterns and more important which factors are relevant for successful language learning. For example, children acquiring a minority language, including a signed language, are exposed to less variety of input than children acquiring a more global language. This is because they are living in a smaller linguistic community and with fewer occasions to use the language in everyday life. Despite this reduced input, most native signers are successful language learners. In contrast native language competence is not always achieved in signing deaf children with hearing parents or those with cochlear implants learning a spoken language. A similar outcome but with very different reasons has also been reported for hearing children with language impairment. In these populations acquisition of morphosyntactic aspects is developing atypically ending with an uncomplete linguistic repertoire. The circumstances of exposure during language development tend to differ in significant ways with respect to a large number of factors, such as, (i) length, quality and quantity of input, (ii) social status and attitudes toward the language, (iii) cognitive abilities required for language learning, and (iv) age of first exposure. Having early exposure to a range of different speakers is important in the acquisition of any language and may affect language proficiency. However, negative societal attitudes or a cognitive based disadvantage may create an unfavourable learning environment that prevents language learning from surfacing typically. This situation inevitably generates a different type of exposure for the child and consequently different language competence. In this Research Topic we intend to encourage the debate on social, linguistic and cognitive factors at play for designing an effective environment for language acquisition aiming at integrating linguistic variables coming from theoretical studies on language with environmental variables, such as, measures of language input or cognitive abilities on functions ancillary to language development.

This volume is dedicated to the field of Specific Language Impairment (SLI), addressing important research questions, including: the interrelation of genetic and cognitive profiles of individuals with SLI; the comorbidity issue and clinical boundaries between SLI and other developmental disorders; cross-linguistic manifestations of SLI; and theory-motivated therapy approaches to individuals with SLI. This volume brings together researchers with different scientific backgrounds and research disciplines, challenging current points of view and offering new perspectives on issues of SLI and developmental disorders.

Is normal language acquisition possible in spite of serious intellectual impairment? The answer, it would appear, is positive. This book summarizes and discusses recent evidence in this respect.

This unique, edited book bridges studies in language disorders and linguistic theory with timely contributions from leading scholars in language development. It presents an attempt to define Specific Language Impairment, relating it to children of normal and disordered language capabilities. The chapter presentations examine language development across a variety of populations of children, from those with Specific Language Impairment to second language learners. The contributors discuss criteria for the definition of SLI, compare and contrast SLI with profiles of children with other disorders and dialects, and offer a comprehensive look at the Whole Human Language, which ties together spoken and signed languages. Methodological concerns that affect the credibility and generalizability of the findings are discussed and controversies between opposing linguistic approaches to language acquisition are presented. The conceptual thread that gradually reveals itself as the chapters unfold is a theoretical issue of central importance to cognitive theory, as well as to our understanding of the biological correlates of language--it concerns the variability that linguistic competence can manifest in children under different biological conditions and life circumstances. Language Competence Across Populations: Toward a Definition of Specific Language Impairment is an essential volume for advanced students and scholars in linguistics and psychology who have an interest in language acquisition and language disorders, as well as for the clinical professionals dealing with children with language impairments.

Acquisition of the native language proceeds in a stage-wise manner for both typically developing (TD) children and children with developmental language disorder (DLD). As shown in TD children learning Dutch and German, the ability to establish contextual cohesion serves as the driving force to proceed from a simple, lexical system to a more complex, functional system. It is argued that precisely this ability is challenged in children with DLD. The present book offers an account of the functional linguistic features fit to achieve contextual cohesion in language production. It provides a rationale for practitioners to develop linguistically founded tools to be used in speech therapy.