DOCSLIB.ORG

Representation, Repair, and Well-Formedness

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Representation, Repair, and Well-Formedness SOUND STRUCTURE REPRESENTATION, REPAIR AND WELL-FORMEDNESS: GRAMMAR IN SPOKEN LANGUAGE PRODUCTION by Adam B. Buchwald A dissertation submitted to The Johns Hopkins University in conformity with the requirements for the degree of Doctor of Philosophy Baltimore, Maryland September 2005 © Adam B. Buchwald All rights reserved Sound structure representation, repair and well-formedness: Grammar in spoken language production ABSTRACT Among the set of processes posited in psycholinguistic theories of spoken language production is the translation (or ‘mapping’) from a basic representation of sound structure retrieved from long-term memory to a more elaborated representation that may engage motor planning and implementation subsystems. In linguistic theory, the phonological grammar is defined as the computation required to generate the set of well-formed ‘output’ representations from a (typically less-elaborated) ‘lexical’ representation. This dissertation is concerned with unifying these ideas, and characterizing the ‘grammar’ in the spoken language production system, focusing on the representations active in the spoken production grammar as well as the well-formedness constraints on the ‘output’ representations. The data used to address these issues are primarily from the spoken production patterns of a brain-damaged individual, VBR. VBR’s impairment is shown to reflect impairment to the spoken production ‘grammar,’ and the pattern of errors she produces are characterized as ‘repairs’ instituted by this grammar. One notable pattern is the insertion of a vowel into word-initial obstruent-sonorant consonant clusters (e.g., bleed → [bəlid]). An acoustic and articulatory investigation presented here suggests that this error arises from a discrete insertion of a vowel, and not from either articulatory ‘noise’ or from a ‘mis’-timing of the articulations associated with the consonants. It is argued that this requires a system of sound structure representation that permits the grammar to insert discrete sound structure units into the articulatory plan. VBR does not insert a vowel on every production token of these forms, and there is variability in the rate of vowel insertion depending on the identity of the onset consonants. This variability is taken to reflect that a speaker’s spoken production grammar distinguishes ‘degrees of well-formedness’ among forms that occur in their language. Another investigation seeks to identify the source of this type of grammatical knowledge. Based on a consonant cluster production study with VBR, it is argued that the spoken production grammar encodes both cross-linguistic regularities of sound structure representation as well as language-particular regularities reflecting the frequency of certain sound structure sequences in the words in a speaker’s lexicon. Jakobson (1941/1968) has famously argued that the same principles that govern cross-linguistic regularities of sound structure also govern patterns of production in cases of ‘language loss.’ A novel test of this claim is presented, in which it is shown that VBR’s grammar is constrained by the same principles that account for the grammar of English. Crucially, it is shown that vowel insertion is the strategy used to repair consonant clusters, while a different strategy is used to repair other complex forms which her grammatical impairment causes her to avoid. The results of these studies are integrated with a view of the spoken production processing system that contains a ‘grammar’ component. This proposal unifies the rich representational descriptions of sound structure and well-formedness constraints in linguistic theory with the process-oriented descriptions of psycholinguistic theory. Advisors: Drs. Brenda Rapp and Paul Smolensky ii ACKNOWLEDGEMENTS As with all work of this scope, this dissertation was made possible by the help and support of many people. I would like to first thank VBR for her enthusiastic participation in this research, and for her great sense of humor and kindness, making the research time as enjoyable as possible. For my training as a cognitive scientist, I am deeply grateful to my advisors, Brenda Rapp and Paul Smolensky, as each are among the most clear-thinking and insightful people I have ever encountered. Brenda’s guidance throughout my tenure at Hopkins has been invaluable. She has taught me – both explicitly and by example – how to think through academic problems thoroughly. Although it is nearly unthinkable that I won’t be popping my head in her office daily in the coming years, it is reassuring that her influence on me will last throughout my tenure in academia and beyond. Paul has been equally influential in my growth throughout my time in graduate school. Paul is deeply committed to cognitive science, and his absurdly keen sense of the ‘big picture’ continuously points me toward exciting ways to ask the types of questions necessary to integrate work from different disciplines. I am particularly grateful for our powwows – our regular conversations epic in both length and scope that always leave me with a sense that my work is important (an easy thing to lose track of in graduate school). This work would also not have been possible without Maureen Stone and the entire Vocal Tract Visualization lab – particularly Marianne Pouplier and Melissa Epstein. Maureen is a pleasure to work with, and her kindness in taking on a student that knew nothing regarding phonetics at the time was matched by her ability both as a scientific collaborator and as a mentor. I could not have chosen a more appropriate and supportive academic environment than the Cognitive Science department at Johns Hopkins. Among the faculty, I am extremely appreciative to Mike McCloskey, Luigi Burzio, Geraldine Legendre, and Bob Frank for their insightful commentary on my work over the last five years. I would also like to thank Matt Goldrick, who has been an unofficial academic mentor of mine since I started at Hopkins. Moreover, I cannot overstate how appreciative I am to all of the undergraduate research assistants that have helped me over the years, especially Joanna Kochaniak. Equally important as the academic influences, I am also grateful to the many friends who have helped make my time in Baltimore more enjoyable than I could have imagined five years ago. Within the department, I am extremely grateful to have had the opportunity to ‘grow up with’ (in alphabetical order): Danny Dilks, Jared Medina, Laura Lakusta, Lisa Davidson, Matt Goldrick, Oren Schwartz, Tamara Nicol and Virginia Savova; as well as my ‘newer’ friends Ari Goldberg, Becca Morley, and Ehren Reilly. I also thank Vanessa Bliss and especially Louisa Conklin for keeping me sane outside of school while writing this thesis. Thanks also to my dissertation committee – Brenda Rapp, Paul Smolensky, Maureen Stone, Greg Ball, and Justin Halberda. Thank you for taking time out to read my thesis and for your useful and insightful commentary. Lastly, I’d like to thank my mother Mary, my father Charles, and my brother David for being there for me throughout the ups and downs of life before, during, and iii after graduate school. Their continuing emotional support has led me to forget at times the unfortunate fact that we live in different cities. iv TABLE OF CONTENTS Abstract…………………………………………………………………………………....ii Acknowledgements…………………………………………………………………….....iv Table of Contents…………………………………………………………………….........v List of Tables.…………………………………………………………………………....vii List of Figures……………………………………………………………………...........viii Chapter One: Introduction ______________________________________________ 1 1.1 ‘Grammar’ in spoken production _______________________________________ 1 1.1.1 Representations of sound structure __________________________________________ 2 1.1.2 Well-formedness conditions ________________________________________________ 3 1.1.3 The source of grammatical knowledge in spoken production _____________________ 4 1.2 Outline of the dissertation _____________________________________________ 6 Chapter Two. Representations, constraints, and repairs in Phonological Processing _____________________________________________________________________ 8 2.0 Introduction_________________________________________________________ 8 2.1 Representations of sound structure______________________________________ 8 2.1.1 Subsegmental representations ______________________________________________ 9 2.1.2 Segmental representations ________________________________________________ 10 2.1.3 Suprasegmental representations ___________________________________________ 11 2.1.4 Formal theories of Grammar ______________________________________________ 12 2.1.5 Summary ______________________________________________________________ 18 2.2 Well-formedness of sound structure representations ______________________ 18 2.3 Phonological processing: Representations and Frameworks ________________ 22 2.3.1 Levels of representation in spoken production processes _______________________ 23 2.3.2 Cognitive Architecture of Spoken Production ________________________________ 26 2.4 Phonological processing and aphasia ___________________________________ 30 2.4.1 Markedness and aphasic speech errors: Group studies_________________________ 31 2.4.2 Markedness and Aphasia: Single-case and case series studies ___________________ 33 2.5 Summary __________________________________________________________ 36 Chapter Three. Case Report ____________________________________________ 37 3.1 Case Report: VBR___________________________________________________
Load more

Recommended publications
  • A New Test for Exemplar Theory: Varying Versus Non-Varying General Linguistics Glossa Words in Spanish
    a journal of Pycha, Anne. 2017. A new test for exemplar theory: Varying versus non-varying general linguistics Glossa words in Spanish. Glossa: a journal of general linguistics 2(1): 82. 1–31, DOI: https://doi.org/10.5334/gjgl.240 RESEARCH A new test for exemplar theory: Varying versus non-varying words in Spanish Anne Pycha University of Wisconsin, Milwaukee, US [email protected] We used a Deese-Roediger-McDermott false memory paradigm to compare Spanish words in which the phonetic realization of /s/ can vary (word-medial positions: bu[s]to ~ bu[h]to ‘chest’, word-final positions:remo [s] ~ remo[h] ‘oars’) to words in which it cannot (word-initial positions: [s]opa ~ *[h]opa ‘soup’). At study, participants listened to lists of nine words that were phonological neighbors of an unheard critical item (e.g., popa, sepa, soja, etc. for the critical item sopa). At test, participants performed free recall and yes/no recognition tasks. Replicating previous work in this paradigm, results showed robust false memory effects: that is, participants were more likely to (falsely) remember a critical item than a random intrusion. When the realization of /s/ was consistent across conditions (Experiment 1), false memory rates for varying versus non-varying words did not significantly differ. However, when the realization of /s/ varied between [s] and [h] in those positions which allow it (Experiment 2), false recognition rates for varying words like busto were significantly higher than those for non-varying words likesopa . Assuming that higher false memory rates are indicative of greater lexical activation, we interpret these results to support the predictions of exemplar theory, which claims that words with heterogeneous versus homogeneous acoustic realizations should exhibit distinct patterns of activation.
    [Show full text]
  • The Emergence of Obstruents After High Vowels*
    John Benjamins Publishing Company This is a contribution from Diachronica 29:4 © 2012. John Benjamins Publishing Company This electronic file may not be altered in any way. The author(s) of this article is/are permitted to use this PDF file to generate printed copies to be used by way of offprints, for their personal use only. Permission is granted by the publishers to post this file on a closed server which is accessible to members (students and staff) only of the author’s/s’ institute, it is not permitted to post this PDF on the open internet. For any other use of this material prior written permission should be obtained from the publishers or through the Copyright Clearance Center (for USA: www.copyright.com). Please contact [email protected] or consult our website: www.benjamins.com Tables of Contents, abstracts and guidelines are available at www.benjamins.com The emergence of obstruents after high vowels* David R. Mortensen University of Pittsburgh While a few cases of the emergence of obstruents after high vowels are found in the literature (Burling 1966, 1967, Blust 1994), no attempt has been made to comprehensively collect instances of this sound change or give them a unified explanation. This paper attempts to resolve this gap in the literature by introduc- ing a post-vocalic obstruent emergence (POE) as a recurring sound change with a phonetic (aerodynamic) basis. Possible cases are identified in Tibeto-Burman, Austronesian, and Grassfields Bantu. Special attention is given to a novel case in the Tibeto-Burman language Huishu. Keywords: epenthesis, sound change, aerodynamics, exemplar theory, Tibeto- Burman, Austronesian, Niger-Congo 1.
    [Show full text]
  • Perception of Non-Phonological Reduction: a Case Study for Using Experimental Data to Investigate Rule-Based Phonology and Exemplar Theory
    W&M ScholarWorks Undergraduate Honors Theses Theses, Dissertations, & Master Projects 7-2012 Perception of Non-Phonological Reduction: A Case Study for Using Experimental Data to Investigate Rule-Based Phonology and Exemplar Theory Rachael Tatman College of William and Mary Follow this and additional works at: https://scholarworks.wm.edu/honorstheses Part of the Linguistics Commons Recommended Citation Tatman, Rachael, "Perception of Non-Phonological Reduction: A Case Study for Using Experimental Data to Investigate Rule-Based Phonology and Exemplar Theory" (2012). Undergraduate Honors Theses. Paper 492. https://scholarworks.wm.edu/honorstheses/492 This Honors Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Undergraduate Honors Theses by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Perception of Non-Phonological Reduction: A Case Study for Using Experimental Data to Investigate Rule-Based Phonology and Exemplar Theory Rachael Tatman May 9, 2012 Contents 1 Introduction and Background 3 1.1 Rule-Based Phonology . 5 1.2 Exemplar Theory . 6 1.3 Coronal Stop to Flap Reduction in American English . 6 2 Experiment 1 9 2.1 Methodology . 10 2.1.1 Items . 10 2.1.2 Procedure . 13 2.1.2.1 Participants . 14 2.2 Results . 15 2.3 Discussion . 15 3 Experiment 2 18 3.1 Methodology . 18 3.1.1 Items and Procedure . 18 3.1.2 Participants . 19 3.2 Results . 19 3.3 Discussion . 20 3.4 Discussion of Experiments 1 and 2 .
    [Show full text]
  • Sociolinguistics Meets Exemplar Theory: Frequency and Recency Effects in (Ing)
    University of Pennsylvania Working Papers in Linguistics Volume 13 2007 Issue 2 Selected Papers from NWAV 35 Article 3 October 2007 Sociolinguistics Meets Exemplar Theory: Frequency and Recency Effects in (ing) Łukasz Abramowicz University of Pennsylvania Follow this and additional works at: https://repository.upenn.edu/pwpl Recommended Citation Abramowicz, Łukasz (2007) "Sociolinguistics Meets Exemplar Theory: Frequency and Recency Effects in (ing)," University of Pennsylvania Working Papers in Linguistics: Vol. 13 : Iss. 2 , Article 3. Available at: https://repository.upenn.edu/pwpl/vol13/iss2/3 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/pwpl/vol13/iss2/3 For more information, please contact [email protected]. Sociolinguistics Meets Exemplar Theory: Frequency and Recency Effects in (ing) This conference paper is available in University of Pennsylvania Working Papers in Linguistics: https://repository.upenn.edu/pwpl/vol13/iss2/3 Sociolinguistics Meets Exemplar Theory: Frequency and Recency Effects in (ing) Łukasz Abramowicz* 1 Introduction In recent years phonological theory has seen the rise of usage-based thinking about speech production, perception, and storage of phonological representa- tions (for two representative collections of papers, see Barlow and Kemmer 2000, and Bybee and Hopper 2001). The term “usage-based” encompasses a rather wide range of approaches, from Exemplar Theory (Pierrehumbert 2001a, 2001b, Bybee 2000) to Cognitive Grammar (Langacker 1987), but two central insights are shared
    [Show full text]
  • 1 Three Waves of Variation Study
    1 Three Waves of Variation Study: The emergence of meaning in the study of variation Penelope Eckert Stanford University Abstract The treatment of social meaning in variation has come in three waves of analytic practice. The first wave of variation studies established broad correlations between linguistic variables and the macro-sociological categories of socioeconomic class, sex class, ethnicity and age. The second wave employed ethnographic methods to explore the local categories and configurations that inhabit, or constitute, these broader categories. In both waves, variation was seen as marking social categories. This paper sets out a theoretical foundation for the third wave, arguing that (1) variation constitutes a robust social semiotic system, expressing the full range of social concerns in a given community; (2) variation does not simply reflect, but constructs, social meaning, hence is a force in social change and (3) the meanings of variables are basic and underspecified, gaining more specific meanings in the context of styles (personae). 1. The fate of social meaning in the study of variation The first quantitative community study of variation was all about social meaning. Based on ethnographic observations and interviews on Martha's Vineyard, William Labov (Labov 1963) established that the pronunciation of /ay/ had been recruited as an indexical resource in a local ideological struggle. This diphthong had a centralized nucleus in the Vineyard dialect, but for some years, island speakers had been following the mainland trend to lower the nucleus to [ɑ]. Labov found that some speakers were reversing this lowering trend, in an apparent move to recapture one of the most salient features of the distinctive island dialect.
    [Show full text]
  • Curriculum Vitae
    Anne Pycha Associate Professor Department of Linguistics University of Wisconsin, Milwaukee Milwaukee, WI 53201 U.S.A. [email protected] http://people.uwm.edu/pycha/ Current as of: January, 2021 A. Background information 1. Formal education 2008 Ph.D, Linguistics, University of California, Berkeley 1993 B.A. with honors, Religious Studies, Brown University, Providence, Rhode Island 2. Doctoral Thesis Morphological Sources of Phonological Length Advisors: Sharon Inkelas (chair), Keith Johnson, Larry Hyman 3. Academic and Professional Positions Held 2018-present. Associate Professor. Department of Linguistics, University of Wisconsin, Milwaukee. 2012- 2018. Assistant Professor. Department of Linguistics, University of Wisconsin, Milwaukee. 2010-2012. Visiting Assistant Professor. Department of Linguistics, University of Massachusetts, Amherst. 2008-2010. IGERT Post-Doctoral Fellow, Institute for Research in Cognitive Science, University of Pennsylvania. 2002-2008. Graduate student, Linguistics, University of California, Berkeley. 2000-2002. Graduate student, Linguistics, University of Chicago. 1999. Science writer, freelance. 1996-1998. Research associate, Scientific Learning Corporation, Oakland, California 1993-1996. Technical writer, Lotus Development Corporation, Cambridge, Massachusetts 4. Special honors, awards, and research grants Honors and awards 2018. Nominee for UWM Undergraduate Research Mentor of the Year. 2015. Fellow, Kavli Scientist-Writer Workshop, New York University (competitive award for travel, accommodation, and tuition to one-week workshop) 2014. Fellow, Trans-Disciplinary Challenge Seminar on Language, Center for 21st Century Studies, University of Wisconsin, Milwaukee (competitive award for course release) 2007. Abigail Hodgen Publication Award, University of California, Berkeley 2006. Outstanding Graduate Student Instructor Award, University of California, Berkeley Anne Pycha Funding activity 2015, 2016. Submitted proposal. “Listener perception of prefixes, roots, and suffixes.” Principal investigator: Anne Pycha.
    [Show full text]
  • A Phonetic Examination of Voice Onset Time in Dutch and English Bilabial Plosives
    Interference in Early Acquisition Dutch-English Bilinguals: A Phonetic Examination of Voice Onset Time in Dutch and English Bilabial Plosives Student: Mary Bless Student ID: 10619100 Supervisor: Silke Hamann MA General Linguistics Date: 5 July 2015 Table of Contents 1. Introduction 1 2. Theoretical Background 7 2.1. Voice Onset Time and Bilabial Plosives 7 2.2. Bilingualism 12 2.3. Interference 16 2.4. Phonetic Study of Bilingualism 17 2.5. Research Practices 21 3. Data & Methods 24 3.1. Methodology 24 3.2. Analysis 27 3.3. Individual Productions and Abnormalities 31 4. Results 38 4.1. /p/ 38 4.2. /b/ 40 4.3. Significance 42 4.4. Comparisons to VOT in Literature 46 4.5. Explanation through Interference 49 5. Discussion & Conclusion 52 6. References 59 7. Appendix 62 7.1. Experiment Texts 7.2. Participant Background Information 7.3. English /b/ Approximates and Zero VOT 7.4. Dutch /b/ Approximates and Zero VOT ! 1 1. Introduction !There is much interest and debate about how language is acquired in bilingual children. There are several different factors and levels of language which play into this debate, but this paper will seek to look at very small, measurable phonetic differences. This paper will examine the phonetic realizations of bilabial plosives, specifically Dutch [p] and [b] and English [p] and [b] in adult bilingual speakers who were raised speaking both languages, all before the age of 6. While [p] has the same phonological definition in all languages of being a voiceless bilabial plosive, a sound produced by creating a small burst of air with the parting of the lips, subtle characteristics of the sound are unique to different languages.
    [Show full text]
  • BRYAN-DISSERTATION-2019.Pdf
    A SENSORIMOTOR BASIS OF SPEECH COMMUNICATION BY JACOB BRYAN DISSERTATION Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Computer Engineering in the Graduate College of the University of Illinois at Urbana-Champaign, 2019 Urbana, Illinois Doctoral Committee: Professor Stephen E. Levinson, Chair Professor Mark Hasegawa-Johnson Associate Professor Ryan K. Shosted Assistant Professor Lav R. Varshney ABSTRACT This dissertation presents the development of sensorimotor primitives as a means of constructing a language-agnostic model of speech communication. Insights from major theories in speech science and linguistics are used to develop a conceptual framework for sensorimotor primitives in the context of control and information theory. Within this conceptual framework, sen- sorimotor primitives are defined as a system transformation that simplifies the interface to some high dimensional and/or nonlinear system. In the con- text of feedback control, sensorimotor primitives take the form of a feedback transformation. In the context of communication, sensorimotor primitives are represented as a channel encoder and decoder pair. Using a high fidelity simulation of articulatory speech synthesis, these realizations of sensorimotor primitives are respectively applied to feedback control of the articulators, and communication via the acoustic speech signal. Experimental results demon- strate the construction of a model of speech communication that is capable of both transmitting and receiving information, and imitating simple utter- ances. ii To Ann, my partner and teammate in all things worth doing. iii ACKNOWLEDGMENTS Completing my doctoral research and writing this thesis has been among the most challenging and rewarding experiences of my life, and I could not have done it without the love and support of my family and friends.
    [Show full text]
  • A New Test for Exemplar Theory: Varying Versus Non- Varying Words in Spanish Anne Pycha University of Wisconsin - Milwaukee, [email protected]
    University of Wisconsin Milwaukee UWM Digital Commons Linguistics Faculty Articles Linguistics 2017 A new test for exemplar theory: Varying versus non- varying words in Spanish Anne Pycha University of Wisconsin - Milwaukee, [email protected] Follow this and additional works at: https://dc.uwm.edu/linguistics_facart Part of the Spanish Linguistics Commons Recommended Citation Pycha, Anne. 2017. A new test for exemplar theory: Varying versus non-varying words in Spanish. Glossa: a journal of general linguistics 2(1): 82. 1–31, DOI: https://doi.org/10.5334/gjgl.240 This Article is brought to you for free and open access by UWM Digital Commons. It has been accepted for inclusion in Linguistics Faculty Articles by an authorized administrator of UWM Digital Commons. For more information, please contact [email protected]. a journal of Pycha, Anne. 2017. A new test for exemplar theory: Varying versus non-varying general linguistics Glossa words in Spanish. Glossa: a journal of general linguistics 2(1): 82. 1–31, DOI: https://doi.org/10.5334/gjgl.240 RESEARCH A new test for exemplar theory: Varying versus non-varying words in Spanish Anne Pycha University of Wisconsin, Milwaukee, US [email protected] We used a Deese-Roediger-McDermott false memory paradigm to compare Spanish words in which the phonetic realization of /s/ can vary (word-medial positions: bu[s]to ~ bu[h]to ‘chest’, word-final positions:remo [s] ~ remo[h] ‘oars’) to words in which it cannot (word-initial positions: [s]opa ~ *[h]opa ‘soup’). At study, participants listened to lists of nine words that were phonological neighbors of an unheard critical item (e.g., popa, sepa, soja, etc.
    [Show full text]
  • Sound Salience and the Exemplar-Based Account
    Phonetic convergence of Hong Kong English: sound salience and the exemplar-based account Wenling Cao (Grace) University of York, UK [email protected] ABSTRACT aiming to provide some preliminary thoughts on the question. A convergence study on Hong Kong Previous theories of convergence either focus on the English (HKE) is reported too. motivation of convergence or address the autonomy of convergence in a dialogue. However, neither of 2. THE EXEMPLAR-BASED APPROACH them provides a clear mechanism of how convergence occurs. The present study tries to answer The exemplar-based approach began in the 19th the question by proposing the exemplar-based century in psychology of memory and has been account of speech convergence. It argues that a adopted in many fields; for example, Johnson [3, 4] speaker’s distributions of sound properties keep in speech perception and Pierrehumbert [5, 6] in updating when he/she receives new input from the speech production. environment, and the more salient a sound is, the more it accommodates. An empirical study of Hong 2.1. Exemplar models in speech perception Kong English (HKE) was conducted to examine the Johnson [3] suggests that categorisation is achieved account. Nineteen HKE speakers completed a map by comparing a new input item with each of the task with an RP speaker and with a General American remembered instances/exemplars of each category. English speaker separately for one hour. Their The similarity between the item and each exemplar production of THOUGHT and BATH vowels, determines the activation level of the exemplar. The rhoticity, fricative /z/ and fricative /θ/ were examined greater the similarity, the higher the activation level.
    [Show full text]
  • A Neural Interpretation of Exemplar Theory
    Psychological Review, 2017, 124, 472-482. A Neural Interpretation of Exemplar Theory F. Gregory Ashby & Luke Rosedahl University of California, Santa Barbara Exemplar theory assumes that people categorize a novel object by comparing its similarity to the memory representations of all previous exemplars from each relevant category. Exemplar theory has been the most prominent cognitive theory of categorization for more than 30 years. Despite its considerable success in providing good quantitative fits to a wide variety of accuracy data, it has never had a detailed neurobiological interpretation. This article proposes a neural interpretation of exemplar theory in which category learning is mediated by synaptic plasticity at cortical-striatal synapses. In this model, categorization training does not create new memory representations, rather it alters connectivity between striatal neurons and neurons in sensory association cortex. The new model makes identical quantitative predictions as exemplar theory, yet it can account for many empirical phenomena that are either incompatible with or outside the scope of the cognitive version of exemplar theory. Keywords: Categorization; Exemplar Theory; COVIS; Striatum Introduction One challenge to interpreting exemplar theory at the neu- ral level is to separate the quantitative predictions of the the- Exemplar theory assumes that categorization is a process ory from the cognitive interpretations that are used to justify of learning about the exemplars that belong to the category. those predictions. At the cognitive level, exemplar theory When an unfamiliar stimulus is encountered, its similarity assumes that people access the memory representations of is computed to the memory representation of every previ- all previously seen exemplars. The standard interpretation is ously seen exemplar from each potentially relevant category.
    [Show full text]
  • Voiced Stops in Jamaican Creole* 1. Introduction
    Voiced Stops in Jamaican Creole* Holman Tse ([email protected]) University of Pittsburgh Department of Linguistics 1. Introduction The purpose of this project is to investigate the phonetic implementation of phonologically voiced stops in Jamaican Creole (JC) using spontaneous speech data. As an English-lexifier creole, JC has traditionally been described as having a contrast between voiceless and voiced stops with the voiced stops being pronounced as plosives (Cassidy & LePage 1980). Recent work has shown that this is not always the case for the voiced stops. Devonish & Harry (2004) as well as Harry (2006) have described the voiced stops as phonetically produced as implosives in stressed word-initial position and as plosives elsewhere. Making use of spontaneous speech data, Gooden & Donnelly (2009), have shown implosion to be a variable feature in stressed word-initial context. With acoustic evidence of variation present, this project attempts to address the extent to which this variation may be patterned based on various internal and external factors such as place of articulation, age, gender, or geographical region. This project has important implications for creole linguistics, contact phonology, and sociophonetics. First of all, there is relatively little published work on creole phonology compared to morpho-syntactic aspects of creoles. Furthermore, implosives appear to be a substrate feature in JC. If this is the case then understanding why they are still present in the language and the contexts in which they are found can lead to a better understanding of creole development. Implosives are also a typologically marked class of sounds. This project, thus, also speaks more generally to the question of how phonological systems develop in contact situations.
    [Show full text]