Sign Language Research Contributes to a Better Understanding of Language Acquisition, A Review of Directions in Sign Language Acquisition Directions in Sign Language Acquisition, edited by Gary Morgan and Bencie Woll (Philadelphia: John Benjamins, 2002. 339 pp. Hardcover $60.00. ISBN 9-027234-72-8 [Europe], 1-58811-235-7 [United States])
Directions in Sign Language Acquisition is a collection of current research studies that emphasizes the ways in which knowledge about sign language acquisition can contribute to a better understanding of language and the way in which children acquire it. Inspired by presentations and workshops at the 1999 Congress of the International Association for the Study of Child Language, the book is published as part of this organization's "Trends in Language Acquisition Research" series.
The introduction, by editors Morgan and WoIl, provides an excellent framework for the studies included in the book. The background information and terminology they discuss are also very helpful for readers who are not familiar with sign languages. Morgan and WoIl emphasize that these studies support diversity in theoretical and methodological approaches, in languages studied, and in the geographical and academic backgrounds of the contributors. This diversity generally contributes to broadening the scope of the text, but it also restricts connections between some of the chapters. Although the editors claim that the emphasis of the reported studies is both theoretical and practical, the primary focus is on theory, and readers must extract the applications.
The first chapter, by Marschark, is a review of research on early language development. It is very thorough and provides an excellent conceptual framework for the book but does not introduce any new research. Marschark clearly introduces the role of gesture as a theme that later chapters also address. Another key point he makes is that researchers need to view language as more than a linguistic system and consider it as a social-communicative system. Analysis must go beyond the grammatical structures and features of a language and include the context and interactions in which they occur.
In the second chapter Kamopp provides a description of phonological development in Brazilian Sign Language. Unfortunately, the theoretical background is not written in enough detail for nonphonologists or non-sign-language researchers to follow. he concludes that location and movement features are acquired earlier and more accurately in children's production of signs, whereas the process of acquiring handshapes is slower and involves more errors. These findings are similar to what Marentette (199$) discovered in studying phonological acquisition in American Sign Language.
In the third chapter Hoiting and Slobin introduce the use of the Berkeley Transcription System (BTS) as a tool for sign language research. They imply that using the same standards as the rest of the language acquisition ReId adds credibility to research in sign language acquisition. This also acknowledges transcription as a necessary tool. Hoiting and Slobin state that a transcription system should be designed to answer the questions we have. For example, it is not necessary to focus on detailed phonology when this is not the major interest of the research. Since the point of this chapter is to describe the new tool, they only briefly mention studies in which the BTS was used.
In chapter four Pizzuto discusses research regarding the development of Italian Sign Language in preschool children. She presents a broad spectrum of findings and information, but because of disorganization in her writing some ofhcr points are difficult to follow. Her primary emphasis is on the variability that occurs in children's use of grammatical structures. She accounts for this unevenness in several ways. First, inflectional morphology in signed languages is highly variable because it is often optional, which makes acquisition slow and irregular. second, articulation (phonology) interacts with morphology, adding yet another dimension of variability. Her third point relates to the input that deaf children receive and suggests that children's acquisition should be evaluated relative to the variability in this input.
In chapter five Meier examines the acquisition of verb agreement. This chapter is very well organized and clearly written. Meier begins by explaining the linguistic arguments for calling directionality in verbs "verb agreement" in sign languages. he goes on to discuss the gestural roots to agreement and the ways in which they become grammaticized. he critically compares gestures and signs, including the ways that gestures have historically shaped signs and also how they differ. Meier's arguments are convincing because they are supported with numerous references to a variety of sign languages.
The sixth chapter outlines a well-designed study by Schick that challenges the claim that children use subject-verb-object order before verb agreement in American Sign Language (ASL). It also emphasizes the variability in the surface structures of both children's and adults' sentences, as a result of the many ASL constructions that modify sign order.
The work presented in the chapters by Pizzuto, Meier, and Schick emphasizes a strong connection across studies of sign language acquisition-signed language acquisition focuses on morphological acquisition rather than word order. This is because word order is variable in the adult model; therefore, it represents a "weak" structure grammatically. These three studies all emphasize the importance of space (morphological inflections) versus sequence (word order) in sign language, which is one of the key differences between spoken and visual languages.
In chapter seven Reilly and Anderson examine the acquisition of facial expression (nonmanual morphology) in deaf children learning ASL. They conclude that manual signs take precedence over non-manual behaviors initially. This finding supports the notion that linear, lexical strategies are used prior to complex, simultaneous facial morphology, which is similar to children's using free morphemes prior to bound morphemes in spoken languages. Reilly and Anderson also note that prelinguistic behaviors (negation and emotional facial expressions) do not automatically generalize to the appropriate linguistic contexts. They interpret this as evidence that affect and language are separate systems.
In chapter eight van den Bogaerde and Baker ask the question "Are deaf children bilingual?" They examine this question in the context of signed and spoken Dutch languages. A very positive feature of their study is that they include an examination of the language input (maternal language) the children were receiving, as well as the children's output. The confusion regarding the classification of spoken Dutch and Dutch Sign Language (SLN) is raised. For example, if SLN is accompanied by speech, is it still SLN or is it Dutch? Or is it the "third language" that emerges from intense language contact? These questions also influence the determining of bilingualism. Children producing a mixture of two languages should not be considered bilingual; however, if the input they receive is a mixture of two languages, what else can we expect them to produce?
In chapter nine Kegl refers to research in the development of Nicaraguan Sign Language (ISN) to argue that children are born with language-ready brains. In observing the emergence of ISN through the shared communication of three generations of Deaf people, Kegl proposes some strong and perhaps controversial claims regarding the relationship among gestures, language, and the brain. The foundation for her argument is based on three key principles: Children are born with language-ready brains; gesture and language are distinct systems of human communication; and simply learning gestures does not trigger the first-language acquisition process. Kegl observes that when deaf people, using only gestures, come into contact with each other, the demands for communication increase. They start to use repetition, multiple attempts at conveying a single idea, and feedback when a message is not understood or is misunderstood. These behaviors-repetition, rephrasing, and feedback-trigger first-language acquisition in children exposed to them. As Kegl concludes, "the bridge from gesture to language is built when a child with a language-ready brain is exposed to communication that moves beyond the demands of a simple call system" (252).
The final chapter, by editors Morgan and WoIl, looks at complex sentence development in British Sign Language. They report that the child they studied was initially building a new argument structure with each verb learned, and not until the appearance of complex verb development (at age 3;6) did more rule-based behavior emerge. This finding supports the notion that linking concepts and linguistic forms is accomplished by looking for general, abstract patterns. They also note that combining manual and nonmanual features is difficult and prolongs acquisition-children produce parts of a verb and parts of the nonmanual morphology separately before combining them. Uoth these strategies, looking for patterns and separating morphological structures, are well supported in the literature of spoken language acquisition.
Since one of the purposes of this book is to make connections between research in sign language acquisition and spoken language acquisition, a response from Lieven addressing exactly this issue is most appropriate. She provides a careful and thorough analysis of the research presented, draws cross-linguistic comparisons, and determines commonalities and differences in the ways children learn to segment language and develop utterance-meaning connections. Moreover, she identifies issues in defining and measuring types of productivity and places importance on obtaining an accurate account of language exposure. Lieven astutely acknowledges that although sign language acquisition studies can inform spoken language acquisition, the far more urgent purpose for this work is to address the problem of providing better access to sign language for all deaf children than is currently the case.
In conclusion, this text provides an excellent compilation of current sign language acquisition research. It also begins to make connections among the ways in which sign language research can contribute to an overall understanding of language and, more specifically, to the acquisition of language. Future directions need to include more research on sign language and the brain; issues of bilingualism in language acquisition; the Deaf community and research, transcription, and coding of data; lexical development; and studies of developmentally atypical signers. As Morgan and WoIl aptly state, "the full contribution of sign language research to the field of child language is still to come" (299).
Marentette, P. F. 1995. It's in Her Hands: A case Study of the Emergence of Phonology in American Sign Language. Ph.D. diss., McGiIl University, Montreal.
Charlotte Evans is Associate Professor in the Department of Education at the University of Manitoba, Winnipeg. Correspondence may be addressed to her at firstname.lastname@example.org.…