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Rachel Walker

Professor of Linguistics

Contact Information
Phone: (213) 740-3674
Office: GFS 301L

Personal Website
Course Information
PhonLunch Schedule


Ph.D. Linguistics, University of California, Santa Cruz
M.A. Linguistics, University of Toronto

Description of Research

Summary Statement of Research Interests

Professor Walker’s research explores systematic speech sound patterns in language and their implications for the theory of grammar. Areas of interest include phonological theory, the role of speech production and perception in phonology, and the phonology-morphology interface. Her primary research focus is on phenomena that involve sound segments (i.e. consonants and vowels) and the features that define sound segments (such as whether the sound is nasal or oral, labial or dental, etc.). Topics she examines include assimilation (processes that cause sounds to become more alike one another in a word), co-occurrence restrictions (the exclusion of certain sound combinations in a word), reduplication (the repetition of speech sounds in word formation), and prominence (e.g. sound segment patterns correlated with stressed syllables). Her recent research has centered on harmony patterns, which are assimilations that potentially affect multiple sound segments or that operate at a distance (across other segments). Her investigations have encompassed vowel harmony, consonant harmony, and nasal consonant-vowel harmony. This work explores local versus non-local dependencies and their typological correlates. At issue are both formal representations and constraints as well as their phonetic or psycholinguistic grounding. Contributions include both individual case studies and cross-language typologies leading to concrete advances in our understanding of the phenomena and their surrounding issues. Research on these topics has involved the study of languages from diverse language families, especially Altaic, Amazonian, Niger-Congo and Romance.

Research Specialties

Phonology, phonetics, morphology

Affiliations with Research Centers, Labs, and Other Institutions

Hearing and Communication Neuroscience,
USC Phonetics and Phonology Group,



Walker, R. (2011). Vowel Patterns in Language. Cambridge: Cambridge University Press.
Walker, R. (2000). Nasalization, Neutral Segments and Opacity Effects. New York: Garland.

Book Chapter

Proctor, M., Walker, R. (2012). Articulatory bases of sonority in English liquids. The Sonority Controversy pp. 289-316. Berlin: Mouton de Gruyter.
Rose, S., Walker, R. (2011). Harmony systems. The Handbook of Phonological Theory, 2nd Edition pp. 240-290. Oxford: Wiley-Blackwell.
Walker, R. (2011). Nasal harmony. The Blackwell Companion to Phonology pp. 1838-1865. Oxford: Wiley-Blackwell.
Walker, R. (2003). Reinterpreting transparency in nasal harmony. The Phonological Spectrum: Segmental Structure (Vol. 1). pp. 37-72. Amsterdam: John Benjamins.

Journal Article

Walker, R. (2014). Nonlocal trigger-target relations. Linguistic Inquiry. Vol. 45, pp. 501-523.
Walker, R. (2012). Vowel harmony in Optimality Theory. Language and Linguistics Compass. Vol. 6 (9), pp. 575-592.
Walker, R. (2010). Nonmyopic harmony and the nature of derivations. Linguistic Inquiry. Vol. 41 (1), pp. 169-179.
Walker, R., Byrd, D., Mpiranya, F. (2008). An articulatory view of Kinyarwanda coronal harmony. Phonology. Vol. 25, pp. 499-535.
Walker, R. (2007). Nasal and oral consonant similarity in speech errors: Exploring parallels with nasal consonant harmony. Language and Cognitive Processes. Vol. 22 (7), pp. 1-41.
Walker, R. (2005). Weak triggers in vowel harmony. Natural Language and Linguistic Theory. Vol. 23, pp. 917-989.
Rose, S., Walker, R. (2004). A typology of consonant agreement as correspondence. Language. Vol. 80, pp. 475-531.
Walker, R. (2001). Round licensing, harmony, and bisyllabic triggers in Altaic. Natural Language and Linguistic Theory. Vol. 19, pp. 827-878.
Walker, R. (2000). Nasal reduplication in Mbe affixation. Phonology. Vol. 17, pp. 65-115.
Walker, R. (1999). Guarani voiceless stops in oral versus nasal contexts: An acoustical study. Journal of the International Phonetic Association. Vol. 29 (1), pp. 63-94.
Walker, R., Pullum, G. K. (1999). Possible and impossible segments. Language. Vol. 75 (4), pp. 765-780.


Walker, R., Mpiranya, F. (2006). On triggers and opacity in coronal harmony. In Rebecca T. Cover and Yuni Kim (Ed.), pp. 383-394. Berkeley, CA. Proceedings of the Berkeley Linguistics Society 31.
Walker, R. (2004). Vowel Feature Licensing at a distance: Evidence from Northern Spanish language varieties. In Vineeta Chand, Ann Kelleher, Angelo J. Rodriguez, and Benjamin Schmeiser (Ed.), pp. 787-800. Proceedings of WCCFL 23/Cascadilla Press.
Walker, R., Feng, B. (2004). A ternary model of morphology-phonology correspondence. In Vineeta Chand, Ann Kelleher, Angelo J. Rodriguez, and Benjamin Schmeiser (Ed.), pp. 773-786. Proceedings of WCCFL 23/Cascadilla Press.
Walker, R. (2002). Yuhup prosodic morphology and a case of augmentation. In Masako Hirotani (Ed.), pp. 551-562. Proceedings of the North East Linguistic Society 32/GLSA.
Walker, R. (2001). Positional markedness in vowel harmony. In Caroline Féry, Antony Dubach Green, and Ruben van de Vijver (Ed.), pp. 212-232. Proceedings of HILP 5, Linguistics in Potsdam, Vol. 12/University of Potsdam.
Walker, R. (2000). Yaka nasal harmony: Spreading or segmental correspondence?. In Lisa J. Conathan, Jeff Good, Darya Kavitskaya, Alyssa B. Wulf, and Alan C. L. Yu (Ed.), pp. 321-332. Berkeley, CA. Proceedings of the Berkeley Linguistics Society 26.
Walker, R. (2000). Long-distance consonantal identity effects. In Roger Billerey and Brook Lillehaugen (Ed.), pp. 532-545. Proceedings of WCCFL 19/Cascadilla Press.
Walker, R. (1996). A third parameter for unbounded stress. In Kiyomi Kusumoto (Ed.), pp. 441-455. Proceedings of the North East Linguistic Society 26/GLSA.
Cohen, M. M., Walker, R. L., Massaro, D. W. (1996). Perception of synthetic visible speech. In David G. Stork and Marcus E. Henneke (Ed.), pp. 153-168. Berlin. Speechreading by Humans and Machines: Models, Systems, and Applications/Springer-Verlag.
Walker, R. (1995). Hierarchical opacity effects in nasal harmony. In Janet Fuller, Ho Han, and David Parkinson (Ed.), pp. 318-332. Proceedings of the Eastern States Conference on Linguistics 11/DMLL Publications.

Honors and Awards

USC Center for Excellence in Teaching, Faculty Fellow, 2012-2013   
USC-Mellon Mentoring Award in the category of Faculty Mentoring Graduate Students, Spring 2008   

Service to the Profession

Editorships and Editorial Boards

Associate Editor, Phonetica, 2014-  
Associate Editor, Natural Language and Linguistic Theory, 2013-  
Advisory Board, Oxford Studies in Phonology, 2013-  
Phonetics and Phonology Editorial Board, Language and Linguistics Compass, 01/2007-  
Editorial Board, Natural Language and Linguistic Theory, 01/2006-12/2012  

Professional Offices

Executive Board Member, Phi Kappa Phi All-University Society, USC Chapter, 2009-2014  
Executive Committee Member, Linguistic Society of America, 01/2009-01/2012  

Professional Memberships

Association for Laboratory Phonology, 2010-  
Acoustical Society of America, 2002-  
Linguistic Society of America, 1994-  
Canadian Linguistic Association, 1992-  
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