XIII SAMENVATTING XV ACKNOWLEDGEMENTS XVII 1. INTRODUCTION 1 1.1 The Aims 1 1.2 The Contributions 3 1.3 The Background 4 1.4 The Model 4 1.5 The Results 5 1.6 How to Read the Thesis 6 2. THE THEORETICAL BACKGROUND 9 2.1 Universal Tendencies of Human Sound Systems 9 2.1.1 Regularities of systems of speech sounds. 10 2.1.2 Regularities of speech sound sequences. 11 2.1.3 Explanations of regularities based on features. 11 2.1.4 Stevens' quantal theory of speech. 12 2.1.5 Carr' s distinctive region model. 12 2.1.6 Predicting sound systems as a whole. 13 2.1.7 How sound systems have become optimised. 14 2.1.8 Glotin' s AGORA model. 15 2.1.9 Berrah' s ESPECE model. 15 2.2 Steels' Work 16 2.2.1 Language as an open, complex dynamic system. 17 2.2.2 Language as an adaptive system. 18 2.2.3 Mechanisms of language origins. 18 2.2.4 Arguments against innateness of language. 20 2.3 The Use of Computer Simulations 21 iv 2.4 The Research Questions 22 3. THE SIMULATION 23 3.1 The History of the Simul...

Abstract not found

Abstract not found

“Origins of communicative disorders ” to Elizabeth Bates, and by a grant from the John D. and Catherine T. MacArthur Foundation. We are grateful to Larry Juarez and Meiti Opie The effects of focal brain injury are investigated in the first stages of language development, during the passage from first words to grammar. Parent report and/or free speech data are reported for 53 infants and preschool children between 10- 44 months of age. All children had suffered a single, unilateral brain injury to the left or right hemisphere, incurred before six months of age (usually in the pre- or perinatal period). This is the period in which we should expect to see maximal plasticity, but it is also the period in which the initial specializations of particular cortical regions ought to be most evident. In direct contradiction of hypotheses based on the adult aphasia literature, results from 10- 17 months suggest that children with righthemisphere injuries are at greater risk for delays in word comprehension, and in the gestures that normally precede and accompany language onset. Although there were no differences between left- vs. right-hemisphere injury per se on expressive language, children whose lesions include the left temporal lobe did show significantly greater delays in expressive vocabulary and

The term “aphasia ” refers to acute or chronic impairment of language, an acquired condition that is most often associated with damage to the left side of the brain, usually due to trauma or stroke. We have known about the link between left-hemisphere damage and language loss for more than a century (Goodglass, 1993). For almost as long, we have also known that the lesion/symptom correlations observed in adults do not appear to hold for very young children (Basser, 1962; Lenneberg, 1967). In fact, in the absence of other complications, infants with congenital damage to one side of the brain (left or right) usually go on to acquire language abilities that are well within the normal range (Eisele & Aram, 1995; Feldman, Holland, & Janosky, 1992; Vargha-Khadem, Isaacs, & Muter,

of at least 16 different foreign languages, and a talent for learning new ones that is clearly demonstrated even when the authors present him with the problem of learning Epun, an artificial language with peculiar properties that (according to the theory of grammar embraced by the authors) do not not exist in the real world and could not be acquired by any normal child. I was convinced by the end of the book that Christopher is indeed a fascinating young man, but the authors' agenda goes far beyond biography. They believe that they are describing a true savant; as we shall soon see, I am not sure that premise is correct. They also believe that they have provided incontrovertible evidence for the independence of language from cognition, for the modularity of the various subcomponents that make up the language faculty, and for the idea that Universal Grammar is an innate property of the human mind with tremendous explanatory value in the study of first- and second-language acquisition.

Development and early focal brain injury 2 Over the past ten years, we have made significant progress in addressing key questions concerning deficit and development after early stroke. We found evidence of subtle early impairment and subsequent development in each domain examined. However, the profiles of impairment and development differed across domains. Deficits of language acquisition are initially pervasive in that they are observed following injury to widely distributed brain areas. Spatial analytic deficits exhibit more specific patterns of brain-behavior association, similar to those observed among adults with injury to comparable brain regions. Had we been working in isolation, the separate investigators associated with this project may have reached very different conclusions about the nature of development following early injury. Instead, we were forced to look for ways to resolve the apparent disparity in our cross-domain findings. The model that best fits our data focuses on redefining the nature of early plasticity. Recent animal studies provide strong evidence that plasticity plays a central role in brain development. Brain organization is to a large extent

Children with early brain damage, unlike adult stroke victims, often go on to develop nearly normal language. However, the route and extent of their linguistic development are still unclear, as is the relationship between lesion site and patterns of delay and recovery. Here we address these questions by examining narratives from children with early brain damage. Thirty children (ages 3;7–10;10) with preor perinatal unilateral focal brain damage and their matched controls participated in a storytelling task. Analyses focused on linguistic proficiency and narrative competence. Overall, children with brain damage scored significantly lower than their age-matched controls on both linguistic (morphological and syntactic) indices and those targeting broader narrative qualities. Rather than indicating that children with brain damage fully catch up, these data suggest that deficits in linguistic abilities reassert themselves as children face new linguistic challenges. Interestingly, after age 5, site of lesion does not appear to be a significant factor and the delays we have witnessed do not map onto the lesion profiles observed in adults with analogous brain injuries. 1998 Academic Press More than 120 years ago, research on the effects of unilateral brain injury in adults led to the conclusion that the left hemisphere plays a specialized The research reported here has been supported by NINDS-NIH Grant P250-NS-22343 and NIDCD Grant R29 DC00539. We also thank Judi Fenson, Gretchen Chapman, and Shelley Flores for their help in data collection and transcription as well as the families who have graciously participated in this study. Address correspondence and reprint requests to Judy Snitzer Reilly, San Diego State University,

THIS BOOK BEGAN with a discussion of the psychological debate over the origins of knowledge. Central to that debate is the definition of the concept of innateness. Nativists define innate concepts as those that are acquired or available in the absence of learning. Recent constructivist accounts have attempted to define a level of innate representation that might plausibly emerge in the absence of input and rely entirely on organism-intrinsic factors. The difficulty with both of these accounts lies in the failure to provide a biologically feasible account of precisely what it means for something to be innate. One argument that has been voiced by some psychologists is that defining biological feasibility of an innate factor is the job of the biologist. Psychological models provide characterizations of sensory, motor, perceptual, cognitive, and social abilities, and although they assume that biological systems underpin behavior, the job of the psychologist is ultimately to explain behavior, not biology. It is true that the proper focus of the psychologist is psychology. However, the essential