Carolyn Mervis, PhD - US grants

The general objective of the proposed research is an increased understanding of the acquisition and manifestation of expertise by young children. The particular focus will be on expertise in an everyday skill, the categorization of concrete objects. The proposed research also will serve to test and refine the Principal Investigator's theory of early conceptual development. to accomplish these objectives, five aspects of expertise at categorization within particular domains will be considered. The first aspect is the acquisition of basic level categories (e.g., dog, hammer). Acquisition of large numbers of these categories in a particular domain e.g., mammals, carpenter's tools) represents an early step in acquisition of domain-specific expertise. the second aspect is the acquisition of subordinate level categories (e.g., collie, claw hammer). Acquisition of multiple categories at this level within a domain is a further step in the acquisition of expertise. the third aspect is acquisition of knowledge of the attribute structure of the domain. Experts know more than simply what category an object belongs to; they understand the attribute relationships that obtain within the domain (e.g., for carpenter's tools, objects which are to be used for banging must have heads made of hard material). The fourth aspect is progress from novice to expert in a domain. The fifth aspect is the use of operating principles for early conceptual development. Examination of the use of particular operating principles provides a direct test of the proposed theory. To accomplish these objectives, 12 studies are proposed. The children who will participate in these studies are between ages 2 years and 6 years. the first 11 studies are cross-sectional and involve either experimental or observational techniques. Each is designed to answer specific question about one or more of the aspects of expertise described above. The last study is short-term longitudinal. In this study, a specially designed board game will be used to examine the development of domain-specific expertise, from novice to beginning expert. The results of these studies will provide a solid basis for testing, refining, and expanding the scope of the Principal Investigator's theory of early conceptual development. Importantly, the results also will provide a framework for delineating guidelines for intervention programs designed to facilitate language and conceptual development.

The purpose of the proposed research is to investigate the prelinguistic development and very early language development of children with Down syndrome. The research will focus on the development of babbling, gestures, and sensorimotor morphemes during the prelinguistic period and on lexical development, the major component of initial language acquisition, during the linguistic period. The research is designed to begin to delineate the onset and development of these important prelinguistic and early linguistic phenomena. There are four main objectives. The first is to describe the prelinguistic and early language development of children with Down syndrome, in comparison to normally developing children. The second is to describe the linguistic input provide by the mothers. The third is to describe aspects of mother-child interaction that potentially could have a major impact on early language development. The final objective is to address the potential effect of the factors studied other prelinguistic and lexical development of children with Down syndrome. The proposed project is a longitudinal study of 12 mother-infant with Down syndrome dyads and 12 matched mother-normally developing infant dyads. We will begin the study when the infants are 5 months old, before the onset of babbling. Dyads involving infants with Down syndrome will be followed for 31 months; dyads involve normally developing infants will participate for 19 moths, by which time all children should have begun to produce language referentially. Tape recordings of mother-infant dyads in a play situation, with a standard set of toys, will be made every 6 weeks. In addition, the children's intellectual development and receptive and productive language development will be tested at regular intervals. Data obtained from the play sessions and testing sessions will be used to address the objectives stated above. The results of this study will provide a solid basis for developing theories concerning the roles of child, mother, and mother-child interaction in determining the course of the child's prelinguistic and early lexical development. Importantly, the results also will provide a framework for delineating guidelines for intervention programs designed to enhance mother-child interaction relevant to prelinguistic and early linguistic development.

The general objective of the proposed research is to delineate the developmental relations between language and cognition. The research will focus on early linguistic and cognitive development by three groups of children: children with William syndrome, children with Down syndrome, and normally developing children. Previous researchers have argued that children with Williams syndrome have language skills that exceed their cognitive skills, whereas children with Down syndrome have cognitive skills that are more advanced than their language skills; in general, normally developing children have equivalent levels of linguistic and cognitive skills. Because of the differences in the general nature of the relations between language and cognition for the three populations, inclusion of all three in a single study provides a unique opportunity to investigate the universality or non-universality of specific relations among language and cognition. The proposed research consists of a five year longitudinal study with supplemental studies conducted at specific points in development. Both observational and experimental methodologies will be used. There are four specific objectives. First, a series of general and specific relations between language and cognition will be examined. Second, the reference of children's earliest words will be explored, using observational, quasi- experimental, and experimental procedures. Third, the development and use of lexical operating principles by children with mental retardation will be considered. Finally, general issues of development by children with Williams syndrome and Down syndrome will be addressed. The research will have implications both for theoretical models of the relation between language and cognition and for the design of early cognitive and language intervention for children with developmental disabilities.

The general objective of the proposed research is to delineate the developmental relations between language and cognition. The research will focus on early linguistic and cognitive development by three groups of children: children with William syndrome, children with Down syndrome, and normally developing children. Previous researchers have argued that children with Williams syndrome have language skills that exceed their cognitive skills, whereas children with Down syndrome have cognitive skills that are more advanced than their language skills; in general, normally developing children have equivalent levels of linguistic and cognitive skills. Because of the differences in the general nature of the relations between language and cognition for the three populations, inclusion of all three in a single study provides a unique opportunity to investigate the universality or non-universality of specific relations among language and cognition. The proposed research consists of a five year longitudinal study with supplemental studies conducted at specific points in development. Both observational and experimental methodologies will be used. There are four specific objectives. First, a series of general and specific relations between language and cognition will be examined. Second, the reference of children's earliest words will be explored, using observational, quasi- experimental, and experimental procedures. Third, the development and use of lexical operating principles by children with mental retardation will be considered. Finally, general issues of development by children with Williams syndrome and Down syndrome will be addressed. The research will have implications both for theoretical models of the relation between language and cognition and for the design of early cognitive and language intervention for children with developmental disabilities.

Williams Syndrome (WS) is a complex neurodevelopmental disorder involving mild to moderate mental retardation, an unusual personality profile, infantile hypercalcemia, dysmorphic facial features, and supravalvar aortic stenosis (SVAS). WS is a contiguous gene disorder resulting from submicroscopic deletions of chromosome 7q11.23. The goal of the proposed study is to create a medical and behavioral profile of WS ("a quantifiable assay of the WS behavioral profile") and to use this profile to identify specific genes underlying behavioral features of WS and carryout genotype-phenotype correlation studies. The specific aims include ascertainment and characterization of individuals who have features that overlap with WS; 2) identification and characterization of the cardinal features of the phenotype of WS and phenotypes of individuals with smaller WS deletions; 3) identification of genes responsible for specific phenotypic features of WS through deliniation of a refined physical map of the WS region, cloning and characterization of genomic DNA within this region, and identification of new genes in the region. An initial specific goal is to identify genes responsible for the personality characteristics of WS as well as other specific phenotype features.

PROJECT SUMMARY (Seeinstructions): The overall objective of the proposed research is to delineate, and make sense of, the process of lexical development and its relations to socio-communicative development, grammatical development, and both general and specific aspects of nonlinguistic cognitive development. The research will focus on the language and cognitive development of children with Williams syndrome and children with Down syndrome. Williams syndrome is associated with relative strengths in language (especially concrete vocabulary and grammar) and verbal short-term memory and severe weakness in visuospatial cognition. In contrast, Down syndrome is associated with severe weaknesses in expressive language (especially grammar) and in verbal short-term memory and relative strength in nonlinguistic aspects of cognition. Because of these differences in the general nature of the relations between language and nonlinguistic cognition, inclusion of these two groups of children in the same studies provides a unique opportunity to distinguish factors that are likely to be universal and necessary to language development from those that are specific to particular rates or paths to language development. The proposed research consists of a longitudinal study of early language and cognitive development beginning in late infancy, a longitudinal study of cognitive and language development of school-age children as measured by standardized assessments, and cross-sectional studies of language development, especially socio-communicative development. Both observational and experimental methods will be used. There are three specific aims. The first is to delineate the different types of early lexical growth curves and examinetheir relations to later patterns of language and cognitive development. The second is to examine socio-communicative development and its role in language and cognitive development. The third is to determine the longitudinal trajectories of language and cognitive abilities of children with Williams syndrome and factors that influence these trajectories. The researchwill have implications both for theoretical models of the relations between language and cognitive development and for the design of cognitive, language, and reading intervention for children with developmental or intellectual disabilities.