Incomplete Resyllabification and Ambisyllabic Gestural Coupling in Spanish

1. INTRODUCTION

Resyllabification turns a word-final coda into a derived onset in prevocalic contexts. For Spanish, Harris and Kaisse (1999, p. 137)Harris, J., & Kaisse, E. (1999). Palatal vowels, glides and obstruents in Argentinian Spanish. Phonology, 16(2), 117-190. https://doi.org/10.1017/S0952675799003735
formalize an autosegmental operation (1) that delinks a segment Y from the rhyme Nʹ and reassociates it as an onset to the following syllable Nʺ. Resyllabification is complete in that delinking and reassociation render derived and canonical (i.e. word-level) onsets structurally identical.

An argument often cited by generative phonologists in support of complete resyllabification comes from Hualde’s (1991)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
rule-based account of fricative lenition in the traditional Chinato Spanish (henceforth, CS) variety of western Spain. In the postlexical (i.e. phrase-level) phonology, an aspiration rule targeting coronal obstruents in the syllable rhyme is ordered to apply after resyllabification. Because resyllabification destroys its triggering environment, the aspiration rule applies transparently, affecting only canonical codas. For the analysis to work, derived onsets must be structurally identical to canonical onsets, with no remaining association to the preceding syllable rhyme.¹Another well-known argument for structural identity comes from the pronunciation of Spanish rhotic consonants in word- and prefix-final prevocalic contexts. See Section 6 for further discussion and analysis. Even since the rise of Optimality Theory (henceforth, OT; McCarthy & Prince, 1999McCarthy, J., & Prince, A. (1999). Faithfulness and identity in Prosodic Morphology. In R. Kager, R., Hulst, H., & W. Zonneveld (Eds.), The Prosody-Morphology Interface (pp. 218-309 ). Cambridge University Press. https://doi.org/10.1017/CBO9780511627729
; Prince & Smolensky, 2004Prince, A., & Smolensky, P. 2004. Optimality Theory: Constraint interaction in generative grammar. Wiley-Blackwell. https://doi.org/10.1002/9780470756171.ch1
), which abandons rule ordering and serial derivations in favor of parallel evaluation of output candidates by surface-oriented constraints, most analyses of Spanish phonology still take the structural identity of derived and canonical onsets as a given. To our knowledge, no alternative account of the CS data has been proposed in the OT literature thus far.

More recently, however, the structural identity assumption has been problematized by experimental acoustic studies of Northern-Central Peninsular Spanish (henceforth, NCPS) that uncover subphonemic differences in the realization of intervocalic /s̺/, which is shorter and more voiced in word-final position than in word-medial or word-initial position (Hualde & Prieto, 2014Hualde, J. I. & Prieto, P. (2014). Lenition of intervocalic alveolar fricatives in Catalan and Spanish. Phonetica, 71(2), 109-127. https://doi.org/10.1159/000368197
; Strycharczuk & Kohlberger, 2016Strycharczuk, P. & Kohlberger, M., (2016) Resyllabification reconsidered: On the durational properties of word-Final /s/ in Spanish. Laboratory Phonology 7(1), pp. 1-24. https://doi.org/10.5334/labphon.5
; Torreira & Ernestus, 2012Torreira, F. & Ernestus, M. (2012). Weakening of intervocalic /s/ in the Nijmegen Corpus of Casual Spanish. Phonetica, 69(3), 124-148. https://doi.org/10.1159/000343635
). How to reconcile the phonological evidence in favor of complete resyllabification with the phonetic evidence against it remains a puzzle.

In this article, we first propose an articulatory representation of ambisyllabicity that predicts the shortening of word-final prevocalic /s̺/ as observed in NCPS. The representation is couched within a split-gesture, competitive, coupled oscillator model of the syllable in Articulatory Phonology (Burroni, 2022Burroni, F. (2022). A split-gesture, competitive, coupled oscillator model of syllable structure predicts the emergence of edge gemination and degemination. Proceedings of the Society for Computation in Linguistics, Vol. 5, Article 3. https://doi.org/10.7275/wjq6-wm83
; Goldstein et al., 2006Goldstein, L., Byrd, D., & Saltzman, E. (2006). The role of vocal tract gestural action units in understanding the evolution of phonology. In M. Arbib, (Ed.), Action to Language via the Mirror Neuron System (pp. 215-249). Cambridge University Press. https://doi.org/10.1017/CBO9780511541599
; Goldstein & Pouplier, 2014Goldstein, L., & Pouplier, M. (2014). The temporal organization of speech. In M. Goldrick, V. Ferreira, & M. Miozzo (Eds.), The Oxford handbook of language production (pp. 210-227). Oxford University Press. https://doi.org/10.1093/oxfordhb/9780199735471.013.012
; Hoole & Pouplier, 2015Hoole, P. & Pouplier, M. (2015). Interarticulatory coordination ‒ speech sounds. In M. Redford (Ed.), The handbook of speech production (pp. 133-157). John Wiley & Sons.
; Marin & Pouplier, 2010Marin, S., & Pouplier, M. (2010). Temporal organization of complex onsets and codas in American English: Testing the predictions of a gestural coupling model. Motor Control, 14(3), 380-407. https://doi.org/10.1123/mcj.14.3.380
; Nam, 2007aNam, H. (2007a). A gestural coupling model of syllable structure. (Publication No. 3267328) [Doctoral dissertation, Yale University]. ProQuest Dissertations & Theses Global.
, 2007bNam, H. (2007b). Articulatory modeling of consonant release gesture. International Congress on Phonetic Sciences XVI. Germany. https://www.icphs2007.de/conference/Papers/1648/1648.pdf
, 2007cNam, H. (2007c). Syllable-level intergestural timing model: Split-gesture dynamics focusing on positional asymmetry and moraic structure. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 483-506). De Gruyter Mouton.
; Nam et al., 2009Nam, H., Goldstein, L. & Saltzman, E. (2009). Self-organization of syllable structure: a coupled oscillator model. In F. Pellegrino, E. Marsico, I. Chitoran & C. Coupé (Eds.), Approaches to phonological complexity (pp. 297-328). De Gruyter Mouton. https://doi.org/10.1515/9783110223958.297
; Tilsen, 2017Tilsen, S. (2017). Exertive modulation of speech and articulatory phasing. Journal of Phonetics, 62, 34-50. https://doi.org/10.1016/j.wocn.2017.03.001
; Zsiga, 2011Zsiga, E. (2011). External sandhi in a second language: The phonetics and phonology of obstruent nasalization in Korean-Accented English. Language 87(2), 289-345. https://doi.org/10.1353/lan.2011.0031
, 2020, pp. 202‒210Zsiga, E. (2020). The phonology/phonetics interface. The MIT Press.
). Then, we show how an ambisyllabic gestural coupling representation streamlines the amount of phonological computation required to account for coronal fricative lenition in CS as compared to alternative theoretical approaches. We offer an OT analysis that also predicts typological patterns of coronal fricative aspiration and voicing that are observed across contemporary Spanish varieties. Lastly, an examination of the consequences of ambisyllabicity for the analysis of rhotic consonants leads us to argue that a markedness constraint on the perceptibility of rhotic contrast is responsible for rhotic neutralization in Spanish phonology, which altogether lacks a rule or constraint targeting individual coda rhotics (Bradley, 2005bBradley, T. G. (2005b). Systemic markedness and phonetic detail in phonology. In R. Gess & E. Rubin (Eds.), Experimental and theoretical approaches to Romance linguistics (pp. 41-62). John Benjamins. https://doi.org/10.1075/cilt.272.04bra
, 2006bBradley, T. G. (2006b). Spanish rhotics and Dominican hypercorrect /s/. Probus, 18, 1-33. https://doi.org/10.1515/PROBUS.2006.001
, 2020Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
).

This article is organized as follows. Section 2 gives the relevant historical background and data from CS and presents Hualde’s (1991)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
analysis motivating complete resyllabification. Section 3 reviews the phonetic evidence from NCPS that resyllabification is incomplete. Section 4 proposes an ambisyllabic, competitively coupled split-gesture representation of derived onsets in NCPS. Section 5 presents our OT account of coronal fricative lenition in CS and explores its typological predictions. Section 6 examines rhotic contrast and neutralization in NCPS. Section 7 concludes.

2. CORONAL FRICATIVE LENITION IN CS

We begin with some background on the historical evolution of Spanish anterior coronal sibilants. In Medieval Spanish (henceforth, MS), the voiced dentoalveolar affricate /dz/ and apicoalveolar fricative /z̺/ were in phonological contrast with their voiceless counterparts /ts/ and /s̺/.²Although not examined here, MS also had three non-anterior coronal sibilants: a voiceless prepalatal affricate /tʃ/ and fricative /ʃ/ but only a single voiced prepalatal with affricate [dʒ] and fricative [ʒ] as allophones (Bradley & Lozano, 2022; Hualde, 2013, pp. 250‒252; Penny, 2000, p. 8). Present-day NCPS maintains MS /tʃ/, while MS /ʃ/ and /dʒ~ʒ/ were neutralized to velar /x/ by the end of the 17th century (Núñez-Méndez, 2021, pp. 31, 35‒36, 49). Deaffrication of the dentoalveolars resulted in fricatives /z̪/ and /s̪/. According to most accounts, the voiced sibilants /z̪/ and /z̺/ underwent devoicing and merger with their voiceless counterparts, after which point /s̪/ was interdentalized, giving rise to the contrast between interdental /θ/ and apicoalveolar /s̺/ in present-day NCPS (Hualde, 2014, pp. 150‒154Hualde, J. I. (2014). Los sonidos del español. Cambridge University Press. https://doi.org/10.1017/CBO9780511719943
; Núñez-Méndez, 2021, pp. 29‒31, 35‒36, 49Núñez-Méndez, E. (2021). An overview of the sibilant merger and its development in Spanish. In E. Núñez-Méndez (Ed.), Sociolinguistic approaches to sibilant variation in Spanish (pp. 9-72). Routledge.
; Penny, 2014, pp. 120‒123Penny, R. (2014). Gramática histórica del español, edición actualizada. Editorial Ariel.
; Rost Bagudanch, 2022Rost Bagudanch, A. (2022). More on sibilant devoicing in Spanish diachrony: An initial phonetic approach. Languages 7(1), 27. https://doi.org/10.3390/languages7010027
). MacKenzie (2022MacKenzie, I. (2022). The genesis of Spanish /θ/: A revised model. Languages 7(3), 191. https://doi.org/10.3390/languages7030191
) proposes a revised model of the genesis of /θ/, based on a quantitative analysis of corpus data tracking the change from orthographic <d> to <z> in word-medial preconsonantal contexts, e.g. juzgar for iudgar ‘to judge’ (< Latin iudicare). He argues that the deaffricated reflexes of MS /dz/ and /ts/ underwent dissibilation to non-sibilant /ð/ and /θ/, respectively, before the devoicing process was completed by the 17th century-a view also held by Menéndez Pidal (1987, p. 113)Menéndez Pidal, R. (1987). Manual de gramática histórica española, 19th ed. Espasa Calpe.
.³MacKenzie’s revised model also questions the teleological basis of interdentalization (and velarization, see footnote 2) as a strategy for increasing the perceptual distance between /s̪/ and /s̺/ to avoid contrast neutralization (pace, e.g. Baker & Holt, 2020, pp. 490‒491). MacKenzie (2022, pp. 11−13) argues that dissibilation likely resulted from a listener-driven perceptual reanalysis of /z̪/ and /s̪/ as /ð/ and /θ/, respectively.

In CS, which is the traditional variety of Malpartida de Plasencia in the province of Cáceres, in Extremadura, Spain (Catalán, 1954Catalán, D. (1954). Concepto lingüistico del dialecto ‘chinato’ en una chinato-hablante. Revista de dialectología y tradiciones populares. Consejo Superior de Investigaciones Científicas. https://en.calameo.com/books/00467782022819fecff5e
; Espinosa, 1935Espinosa, A. M. Jr. (1935). Arcaísmos dialectales: La conservación de “s” y “z” sonoras en Cáceres y Salamanca. Revista de Filología Española, Anejo 19.https://en.calameo.com/books/0046778208d1f605f5051
; Hualde, 1991Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
), the anterior coronal sibilants of MS evolved differently compared to NCPS, giving rise to some unexpected correspondences:

These and other similar data come from “texts sent by a native speaker of the dialect, doña Gregoria Canelo, to Ramón Menéndez Pidal in 1904, and that were published and studied by Catalán (1954)Catalán, D. (1954). Concepto lingüistico del dialecto ‘chinato’ en una chinato-hablante. Revista de dialectología y tradiciones populares. Consejo Superior de Investigaciones Científicas. https://en.calameo.com/books/00467782022819fecff5e
” (Hualde, 1991, p. 57)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
, as well as from descriptions by Espinosa (1935)Espinosa, A. M. Jr. (1935). Arcaísmos dialectales: La conservación de “s” y “z” sonoras en Cáceres y Salamanca. Revista de Filología Española, Anejo 19.https://en.calameo.com/books/0046778208d1f605f5051
. We have adapted Canelo’s orthographic renditions into modern IPA. In CS, both [θ] (2)a,b and [ð] (2)c,d appear as canonical onsets in word-medial intervocalic position. Surprisingly, NCPS [s̺] corresponds to interdental [θ] (2)a and [ð] (2)c in CS, which altogether lacks apicoalveolar fricatives. According to Hualde’s (1991, pp. 59‒60)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
historical account of CS, MS apicoalveolar /z̺/ and /s̺/ merged with the deaffricated reflexes of dentoalveolar /dz/ and /ts/, which then were fronted to /ð/ and /θ/, respectively. However, /ð/ did not devoice. CS therefore maintains the MS voicing contrast but neutralizes the place contrast to interdental. The contrast between /ð/ and /θ/ lends further support to MacKenzie’s revised chronology of MS sibilants. In fact, MacKenzie (2022, p. 191, note 15)MacKenzie, I. (2022). The genesis of Spanish /θ/: A revised model. Languages 7(3), 191. https://doi.org/10.3390/languages7030191
cites CS as an example of a variety in which dissibilation of /z̪/ and /s̪/ took place without subsequent devoicing, while at the same time highlighting the loss of apicoalveolar /z̺/ and /s̺/. Word-initially, [θ] and [ð] are not in direct contrast in CS. Of the two fricatives, only [θ] appears after a pause (2)e,g. Espinosa (1935, pp. 78, 102)Espinosa, A. M. Jr. (1935). Arcaísmos dialectales: La conservación de “s” y “z” sonoras en Cáceres y Salamanca. Revista de Filología Española, Anejo 19.https://en.calameo.com/books/0046778208d1f605f5051
gives two examples of voiced plosive [d], after a pause (2)f and a nasal (2)g. Apparently, the dissibilation of /z̪/ to /ð/ in CS led to a phonemic merger between /ð/ and /d/, whereby /ð/ acquired plosive allophones in the same phonological contexts as /d/ (Hualde, 1991, pp. 60−61Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
).

In the synchronic CS grammar, the contrast between /ð~d/ and /θ/ is neutralized by processes of voicing and aspiration outside of the canonical onset environment. Spaces appear in the phrasal examples below to make the word divisions clearer. First, [ð] appears in word-final position before a following vowel (3)a,b and, according to Espinosa (1935, pp. 61, 73)Espinosa, A. M. Jr. (1935). Arcaísmos dialectales: La conservación de “s” y “z” sonoras en Cáceres y Salamanca. Revista de Filología Española, Anejo 19.https://en.calameo.com/books/0046778208d1f605f5051
, in stem-final position before a vowel-initial plural (3)c or derivational (3)d suffix (cf. NCPS [rés̺es], [més̺es], and [luθéɾo].) Second, the glottal fricative [h] appears before a consonant, within the same word (3)e or across word boundaries (3)f, and before a pause (3)a,c, where it variably disappears in utterance-final position, e.g. [lað álah ~ lað ála], [réðeh ~ réðe], etc.

Hualde (1991)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
formalizes two rules targeting coronal obstruents in the syllable rhyme. Coronal Obstruent Voicing (COV) operates as a cyclic, stem-level lexical “constraint or filter on representations that checks the well-formedness of certain segments in certain positions, rather than as an active feature-changing rule” (p. 65). Applying vacuously to underlying final /d/ but actively to final /θ, t/ in loanwords, COV explains why the three-way coronal contrast in [éθo] ‘that’ (2)a, [kóða] ‘thing’ (2)b, and, e.g. [pandeɾéta] ‘tambourine’, is neutralized to intervocalic [ð] in word- and stem-final environments (3)a‒d. The second rule is Coronal Obstruent Aspiration (COA). It applies postlexically to delink supralaryngeal features in the syllable rhyme, leaving behind only the laryngeal features responsible for aspiration, which is transcribed as the glottal fricative [h].

The sample derivations in (4) and (5) illustrate the analysis. Periods denote syllable boundaries, and the + symbol, the morphological boundary between a stem and a derivational affix.

For [lað álah] (3)a, syllabification first takes place within each word separately (4)a, which puts each /d/ in the syllable rhyme. Checkmarks indicate the vacuous application of COV (4)b. Postlexical resyllabification turns the word-final prevocalic coda into a derived onset (4)c. Ordered after the spirantization of postvocalic voiced plosives (4)d and the devoicing of the word-final coda obstruent (4)e, COA applies (4)f, followed by an optional rule of utterance-final glottal fricative deletion (not shown here). The derived onset fricative escapes COA, which applies only to the canonical coda fricative. For [luðéɾo] (3)d, the first cycle of the lexical phonology induces syllabification within the domain of the stem (5)a, where final /d/ in the syllable rhyme satisfies COV (5)b. Adding the derivational suffix triggers a second cycle: stem-final prevocalic /d/ syllabifies as a word-medial onset (5)c, and then COV fails to apply (5)d. The only postlexical rule that can apply in this derivation is Spirantization (5)f. The stem-final canonical onset fricative escapes COA, as does the word-final derived onset fricative (4)f.

COV and COA interact with resyllabification in opposite ways. First, COV is phonologically opaque because the rule ‘overapplies’ in onsets. Overapplication opacity arises because COV is ordered to apply before stem-final codas become derived onsets postlexically (4)c or canonical onsets on a second lexical cycle (5)c. This type of relationship, known as a counterbleeding rule order, is seen as evidence supporting the existence of derivational steps and abstract intermediate representations. Overapplication opacity is problematic for ‘classic’ monostratal OT, in which input-output mappings are evaluated in parallel without serial rule application or intermediate derivational steps (Baković, 2011Baković, E. (2011). Opacity and ordering. In J. Goldsmith, J. Riggle, & A. C. L. Yu (Eds.), The handbook of phonological theory (2nd ed., pp. 40-67). Blackwell Publishing Ltd. https://doi.org/10.1002/9781444343069.ch2
, 2013Baković, E. (2013). Blocking and complementarity in phonological theory. Advances in Optimality Theory series. Equinox Publishing.
). Second, because it is ordered after postlexical resyllabification, COA operates transparently, targeting only canonical codas (4)f. Applying first, resyllabification (4)c destroys the environment that triggers COA, thereby blocking the aspiration of derived onsets. Because COA could still apply if the word-final fricative were to maintain its lexical affiliation to the preceding rhyme, resyllabification must be assumed to be complete, i.e. derived onsets must be structurally identical to canonical onsets.

3. INCOMPLETE RESYLLABIFICATION

Contemporary laboratory phonology has come to question the generative assumption that resyllabification across word boundaries in connected speech is complete. The critique was initiated by phonetic studies of French enchaînement ‘linking’. Gaskell et al. (2002)Gaskell, M. G., Spinelli, E., & Meunier, F. (2002). Perception of resyllabification in French. Memory and Cognition, 30, 798-810. https://dx.doi.org/10.3758/BF03196435
report that French listeners show sensitivity to subphonemic differences between /VC#V/ and /V#CV/ sequences in lexical priming tasks (# denotes a morphological word boundary). According to Fougeron et al. (2003)Fougeron, C., Bagou, O., Alain, C., Stefanuto, M. & Frauenfelder, U. H. (2003). Looking for acoustic cues of resyllabification in French. International Congress on Phonetic Sciences 15. Spain. https://www.internationalphoneticassociation.org/icphs-proceedings/ICPhS2003/p15_2257.html
and Fougeron (2007)Fougeron, C. (2007). Word boundaries and contrast neutralization in the case of enchaînement in French. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 609-642). De Gruyter Mouton.
, French intervocalic consonants in laboratory speech are acoustically shorter as derived onsets than as canonical onsets. Listeners are capable of noticing durational and spectral cues in order to perceive the contrast between such sequences, which is incompletely neutralized (Fougeron, 2007Fougeron, C. (2007). Word boundaries and contrast neutralization in the case of enchaînement in French. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 609-642). De Gruyter Mouton.
). In American English laboratory speech, /l/ and /w/ are found to have less consonantal constriction and more asynchronous timing of intra-segmental tongue tip and tongue body gestures as derived onsets than as canonical onsets, e.g. hall otter vs. ha lotter, how otter vs. ha wadder (Gick, 2004Gick, B. (2004). Articulatory correlates of ambisyllabicity in English glides and liquids. In J. Local, R. Ogden, & R. Temple (Eds.), Phonetic interpretation: Papers in Laboratory Phonology VI (Papers in Laboratory Phonology, pp. 222-236). Cambridge University Press. https://doi.org/10.1017/CBO9780511486425.013
). In British English, patterns of linguopalatal contact in derived onset /l/ differ from those found in canonical onset or coda /l/ (Scobbie & Pouplier, 2010Scobbie, J. M., & Pouplier, M. (2010). The role of syllable structure in external sandhi: An EPG study of vocalisation and retraction in word-final English. /l/ Journal of Phonetics, 38(2), 240-259. https://doi.org/10.1016/j.wocn.2009.10.005
). In American English spontaneous speech, intervocalic consonants are acoustically shorter word-finally than word-initially, e.g. beef eater vs. bee feeder (Tao et al., 2018Tao, J., Torreira, F., & Clayards, M. (2018). Durational cues to word boundaries in spontaneous speech. Proc. Speech Prosody 2018, pp. 240-244, https://doi.org/10.21437/SpeechProsody.2018-49
).

Evidence for incomplete resyllabification in NCPS comes from acoustic studies reporting differences in the realization of apicoalveolar /s̺/ between vowels, depending on the presence and location of a word boundary. The following examples, from Strycharczuk and Kohlberger (2016, p. 5)Strycharczuk, P. & Kohlberger, M., (2016) Resyllabification reconsidered: On the durational properties of word-Final /s/ in Spanish. Laboratory Phonology 7(1), pp. 1-24. https://doi.org/10.5334/labphon.5
, illustrate the three main contexts of interest, namely canonical onset /s̺/ in initial (6)a and medial (6)b positions and derived onset /s̺/ in final position (6)c:

Torreira and Ernestus (2012)Torreira, F. & Ernestus, M. (2012). Weakening of intervocalic /s/ in the Nijmegen Corpus of Casual Spanish. Phonetica, 69(3), 124-148. https://doi.org/10.1159/000343635
collected 1,257 tokens of intervocalic /s̺/, produced in spontaneous conversational speech by 27 female and 25 male speakers from Madrid as part of the Nijmegen Corpus of Casual Spanish, and analyzed voicing based on acoustic measurements of an uninterrupted pitch track during the fricative, as well as intensity differences with surrounding vowels. Of the total tokens of intervocalic /s̺/, 34% were realized with a fully voiced [z̺], more frequently in word-final position, the faster the rate of speech, and the shorter the duration of the fricative. Intervocalic /s̺/ voicing is thus consistent with laryngeal coarticulation, which is known to be sensitive to temporal variation. However, the fact “that voicing is considerably more common in word-final position suggests that this coarticulatory pattern is not an entirely passive phenomenon, and that it may contain the seeds of phonologization” (p. 139).

Hualde and Prieto (2014)Hualde, J. I. & Prieto, P. (2014). Lenition of intervocalic alveolar fricatives in Catalan and Spanish. Phonetica, 71(2), 109-127. https://doi.org/10.1159/000368197
analyzed 684 tokens produced by 16 female speakers from Madrid in directed conversational speech collected via map tasks for the Interactive Atlas of Spanish Intonation. Of the total tokens of intervocalic /s̺/, only 8.3% were fully voiced. Measurements of uninterrupted voicing replicated the findings of Torreira and Ernestus (2012)Torreira, F. & Ernestus, M. (2012). Weakening of intervocalic /s/ in the Nijmegen Corpus of Casual Spanish. Phonetica, 69(3), 124-148. https://doi.org/10.1159/000343635
by revealing higher rates of fully voiced /s̺/ in final (12.5%) than initial (10.64%) or medial (5.93%) position, as well as significantly more voiced frames in final than medial /s̺/. Duration measurements revealed a significantly shorter intervocalic /s̺/ word-finally than initially or medially but no significant difference between the latter two contexts. Derived and canonical /s̺/ should be expected to pattern the same phonetically if Spanish resyllabification were completely neutralizing. Hualde and Prieto suggest that resyllabification is only partial and that a symbolic transcription of más amor ‘more love’ as [má.s̺a.móɾ] “simply offers an incomplete view of phonetic reality” (p. 124). They propose that in /VCV/ and /V#CV/ contexts, the onset consonant is “timed to start in-phase with the following vowel (Nam et al., 2009Nam, H., Goldstein, L. & Saltzman, E. (2009). Self-organization of syllable structure: a coupled oscillator model. In F. Pellegrino, E. Marsico, I. Chitoran & C. Coupé (Eds.), Approaches to phonological complexity (pp. 297-328). De Gruyter Mouton. https://doi.org/10.1515/9783110223958.297
), whereas in /VC#V/ lexical syllabic affiliation may result in a different gestural coordination, even if, as it is generally assumed for Spanish and Catalan, there is postlexical resyllabification” (p. 123).

Evidence from a third study with carefully controlled materials uncovers even more systematic variation in laboratory speech. Strycharczuk and Kohlberger (2016)Strycharczuk, P. & Kohlberger, M., (2016) Resyllabification reconsidered: On the durational properties of word-Final /s/ in Spanish. Laboratory Phonology 7(1), pp. 1-24. https://doi.org/10.5334/labphon.5
used a reading task with two-word stimuli embedded in carrier phrases, eliciting a total of 792 tokens from 1 male and 10 female speakers from northern and central Spain. As summarized in Table 1, an analysis of fricative duration revealed significant contextual differences, except for canonical coda /s̺/:

Between vowels, the fricative was the shortest as a word-final derived onset, but unlike in Hualde and Prieto’s results for spontaneous speech, there was also a difference between canonical onsets: initial /s̺/ was significantly longer than medial /s̺/. Canonical codas were shorter than canonical onsets, with no significant difference between preconsonantal contexts, e.g. meses pasados ‘past months’, seis españoles ‘six Spaniards’. No spectral differences are reported for the surrounding vowels, but a significantly longer preceding vowel in /Vs̺#V/ than in /Vs̺#PV/ (68.26 ms > 60.76 ms) is consistent with the cross-linguistic tendency toward open syllable lengthening, suggesting some type of affiliation between /s̺/ and the following vowel. The duration of derived onset /s̺/, intermediate between canonical onsets and codas, shows that resyllabification was nonetheless incomplete. The implication is that “structural differences between canonical and derived onsets are accessible to learners at a level of linguistic representation that connects directly to phonetic realization” (Strycharczuk & Kohlberger, 2016, p. 17Strycharczuk, P. & Kohlberger, M., (2016) Resyllabification reconsidered: On the durational properties of word-Final /s/ in Spanish. Laboratory Phonology 7(1), pp. 1-24. https://doi.org/10.5334/labphon.5
).

Strycharczuk and Kohlberger consider two possible prosodic representations of incomplete resyllabification. If derived onsets are treated as ambisyllabic, then they should be distinguishable from canonical onsets and codas such that only ambisyllabic consonants will be targets of weakening. However, as the researchers point out, ambisyllabicity is also commonly used to represent intervocalic geminate consonants in many languages, which highlights the theoretical inconsistency of using the same type of syllabic structure to explain two opposing phenomena, i.e. lengthening and shortening. Jensen (2000)Jensen, J. (2000). Against ambisyllabicity. Phonology, 17(2), 187-235. https://doi.org/10.1017/S0952675700003912
raises a similar theoretical critique of the use of ambisyllabicity in generative analyses of segmental strengthening and weakening in English, German, and Danish, as does Purse (2020, pp. 104‒105)Purse, R. (2020). The envelope of variation for /l/ vocalisation in Philadelphia English. University of Pennsylvania Working Papers in Linguistics, 25(2), Article 12. https://repository.upenn.edu/pwpl/vol25/iss2/12
based on an acoustic study of /l/-vocalization in Philadelphia English. As an alternative to ambisyllabicity for singling out derived onsets, Strycharczuk and Kohlberger suggest the possibility of prosodic misalignment, whereby /s̺/ associates to the following syllable onset while remaining associated to the preceding prosodic word. Prosodic word-initial /s̺/ is correctly predicted to be the longest because consonants are independently known to undergo domain-initial strengthening, which increases fricative duration (Fougeron & Keating, 1997Fougeron, C., & Keating, P. A. (1997). Articulatory strengthening at the edges of prosodic domains. The Journal of the Acoustical Society of America, 101, 3728-3740. https://doi.org/10.1121/1.418332
; Keating et al., 2004Keating, P., Cho, T., Fougeron, C., & Hsu, C.-S. (2004). Domain-initial articulatory strengthening in four languages. In J. Local, R. Ogden, & R. Temple (Eds.), Papers in laboratory phonology 6 (pp. 145-163). Cambridge University Press.
; White et al., 2020White, L., Benavides-Varela, S., & Mády, K. (2020). Are initial-consonant lengthening and final-vowel lengthening both universal word segmentation cues? Journal of Phonetics, 81, 1-14. https://doi.org/10.1016/j.wocn.2020.100982
)-an explanation we adopt here. However, as Strycharczuk and Kohlberger highlight, initial strengthening cannot explain why medial /s̺/ should be longer than final /s̺/, as neither fricative is word-initial. Although not statistically significant, in Table 1 the mean duration of coda /s̺/ is longer word-finally in /Vs̺#PV/ than word-medially /Vs̺PV/, which suggests the possibility of lengthening in prosodic word-final position. Unfortunately, final lengthening makes the opposite prediction that intervocalic /s̺/ should be longer word-finally than medially. How to capture the structural difference between canonical and derived onset /s̺/ in NCPS laboratory speech remains elusive.

Ramsammy (2021)Ramsammy, M. (2021). Contextual reduction of word-final /l/ in Spanish: An EPG study. Journal of the International Phonetic Association, 1-28. https://doi.org/10.1017/S0025100321000128
used electropalatography to describe word-final /l/ reduction in the speech of four NCPS speakers from Galicia, based on data from a carrier phrase task involving nonce word stimuli.⁴A reviewer asks about potential language transfer effects from Galician. Two participants were NCPS-Galician bilinguals who reported using NCPS regularly in their daily lives (Ramsammy, 2021, pp. 7‒8). Galician has a clear lateral phoneme /l/ (Regueria, 1996), as does NCPS, which suggests that bilingual interference effects should have been minimal. Linguopalatal contact was the longest and most extensive utterance-finally before a pause but showed varying degrees of reduction before word-initial /a/ and voiceless plosives and fricatives. Because the study did not examine contexts of canonical onset /l/, it remains unclear whether participants showed asymmetrical reduction across /V#lV/, /VlV/ and /Vl#V/ contexts, as Strycharczuk and Kohlberger report for the duration of /s̺/. Still, Ramsammy argues that speaker-specific gestural overlap and reduction strategies provide a better explanation of the contextual variation in word-final /l/ than do differences in syllabification or prosodic structure, paceRubach’s (1996)Rubach, J. (1996). Shortening and ambisyllabicity in English. Phonology, 13(2), 197-237. https://doi.org/10.1017/S0952675700002104
use of ambisyllabicity to explain properties of English word-final prevocalic /l/.

4. A COMPETITIVELY COUPLED SPLIT-GESTURE REPRESENTATION OF AMBISYLLABIC CONSONANTS

This section argues that the shortening of derived onset /s̺/ in NCPS, as documented by Strycharczuk and Kohlberger (2016)Strycharczuk, P. & Kohlberger, M., (2016) Resyllabification reconsidered: On the durational properties of word-Final /s/ in Spanish. Laboratory Phonology 7(1), pp. 1-24. https://doi.org/10.5334/labphon.5
, is predicted to emerge in speech planning from multiple competitive couplings among the fricative’s target and release gestures and the surrounding vowel gestures. In Articulatory Phonology (henceforth, AP; Browman & Goldstein, 1989Browman, C. P., & Goldstein, L. (1989). Articulatory gestures as phonological units. Phonology, 6(2), 201-251. https://doi.org/10.1017/S0952675700001019
, 1990Browman, C. P., & Goldstein, L. (1990). Tiers in articulatory phonology, with some implications for casual speech. In J. Kingston & M. Beckman (Eds.), Papers in Laboratory Phonology (Papers in Laboratory Phonology, pp. 341-376). Cambridge University Press. https://doi.org/10.1017/CBO9780511627736.019
), the grammar operates over dynamically defined movement tasks, or gestures, that instruct the active articulators to constrict the vocal tract during speech production. Abandoning the traditional phonological segment, AP posits that gestures are the ‘atomic’ units of speech production, glued together by coupling relations into larger ‘molecules’ that cohere into word forms during language acquisition (Goldstein et al., 2006, p. 225Goldstein, L., Byrd, D., & Saltzman, E. (2006). The role of vocal tract gestural action units in understanding the evolution of phonology. In M. Arbib, (Ed.), Action to Language via the Mirror Neuron System (pp. 215-249). Cambridge University Press. https://doi.org/10.1017/CBO9780511541599
).

Building on work by Saltzman and Munhall (1989)Saltzman, E. L., & Munhall, K. G. (1989). A dynamical approach to gestural patterning in speech production. Ecological Psychology, 1(4), 333-382. https://doi.org/10.1207/s15326969eco0104_2
, the development of the coupled oscillator model of syllable structure (Goldstein et al., 2006Goldstein, L., Byrd, D., & Saltzman, E. (2006). The role of vocal tract gestural action units in understanding the evolution of phonology. In M. Arbib, (Ed.), Action to Language via the Mirror Neuron System (pp. 215-249). Cambridge University Press. https://doi.org/10.1017/CBO9780511541599
; Goldstein & Pouplier, 2014Goldstein, L., & Pouplier, M. (2014). The temporal organization of speech. In M. Goldrick, V. Ferreira, & M. Miozzo (Eds.), The Oxford handbook of language production (pp. 210-227). Oxford University Press. https://doi.org/10.1093/oxfordhb/9780199735471.013.012
; Hoole & Pouplier, 2015Hoole, P. & Pouplier, M. (2015). Interarticulatory coordination ‒ speech sounds. In M. Redford (Ed.), The handbook of speech production (pp. 133-157). John Wiley & Sons.
; Marin & Pouplier, 2010Marin, S., & Pouplier, M. (2010). Temporal organization of complex onsets and codas in American English: Testing the predictions of a gestural coupling model. Motor Control, 14(3), 380-407. https://doi.org/10.1123/mcj.14.3.380
; Nam et al., 2009Nam, H., Goldstein, L. & Saltzman, E. (2009). Self-organization of syllable structure: a coupled oscillator model. In F. Pellegrino, E. Marsico, I. Chitoran & C. Coupé (Eds.), Approaches to phonological complexity (pp. 297-328). De Gruyter Mouton. https://doi.org/10.1515/9783110223958.297
; Zsiga, 2011Zsiga, E. (2011). External sandhi in a second language: The phonetics and phonology of obstruent nasalization in Korean-Accented English. Language 87(2), 289-345. https://doi.org/10.1353/lan.2011.0031
, 2020, pp. 202‒210Zsiga, E. (2020). The phonology/phonetics interface. The MIT Press.
) makes it possible to represent the temporal coordination of gestures using two basic timing relations. When two gestures G₁ and G₂ are coupled in-phase, they will begin simultaneously, but when coupled anti-phase, G₂ will begin after the midpoint of G₁. The model can be implemented computationally in the Task Dynamics Application (henceforth, TaDA; Browman et al., 2006Browman, C. P., Goldstein, L., Nam, H., Rubin, P., Proctor, M., & Saltzman, E. (2006). TaDA (Task Dynamics Application) Manual. Haskins Laboratories, Inc.
; Goldstein et al., 2006Goldstein, L., Byrd, D., & Saltzman, E. (2006). The role of vocal tract gestural action units in understanding the evolution of phonology. In M. Arbib, (Ed.), Action to Language via the Mirror Neuron System (pp. 215-249). Cambridge University Press. https://doi.org/10.1017/CBO9780511541599
). Coordination relations are formalized as intergestural coupling graphs, in which gestures are nodes that are connected by edges, or association lines, that specify the coupling relation. A solid line denotes in-phase coupling, i.e. G₁―G₂, while a dotted arrow denotes anti-phase coupling of the first gesture to the second one, i.e. G₁⇢G₂. Based on physical principles governing the movement of coupled oscillators, TaDA executes a speech planning process that computes the most stable timing pattern for all the gestures of an utterance at a specified speech rate. The output of the process is a gestural score, which displays gestures on separate tiers that correspond to the active articulators, i.e. Lips, Tongue Tip, Tongue Body, Tongue Root, Velum, and Glottis. Informed by mathematical equations of task dynamics, an interarticulator component then uses the gestural score to derive output movement trajectories that can serve as input for speech synthesis and vocal tract modeling (not examined here).

4.1. The split-gesture hypothesis

 ⌅

Based on simulations in TaDA, Nam (2007aNam, H. (2007a). A gestural coupling model of syllable structure. (Publication No. 3267328) [Doctoral dissertation, Yale University]. ProQuest Dissertations & Theses Global.
, 2007bNam, H. (2007b). Articulatory modeling of consonant release gesture. International Congress on Phonetic Sciences XVI. Germany. https://www.icphs2007.de/conference/Papers/1648/1648.pdf
, 2007c)Nam, H. (2007c). Syllable-level intergestural timing model: Split-gesture dynamics focusing on positional asymmetry and moraic structure. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 483-506). De Gruyter Mouton.
argues for the split-gesture hypothesis, whereby a plosive’s primary constriction gesture is decomposed into separate closure and release gestures (Browman, 1994Browman, C. P. (1994). Lip aperture and consonant releases. In P. Keating (Ed.), Papers in laboratory phonology III: Phonological structure and phonetic form (pp. 331-353). Cambridge University Press. https://doi.org/10.1017/CBO9780511659461
). To model Browman and Goldstein’s (1995)Browman, C. P., & Goldstein, L. (1995). Gestural syllable position effects in American English. In F. Bell-Berti & L. Raphael (Eds.), Studies in speech production: A Festschrift for Katherine Safford Harris (pp. 19-34). American Institute of Physics.
experimental finding that in English /pV/ sequences, the vowel gesture begins around the midpoint between the beginnings of the plosive’s closure and release gestures, Nam argues that the vowel is coupled in-phase with both the closure and release, i.e. CLO―V and REL―V, but that the closure is coupled anti-phase with the release, i.e. CLO⇢REL. The in-phase and anti-phase couplings are competitive in the sense that they place opposite demands on the closure and release gestures. A temporal compromise emerges in speech planning: the closure and release are symmetrically pushed apart in opposite directions in time, with the closure beginning earlier and the release later, while the vowel begins after the closure begins but before the release begins. For experimental data from human subjects confirming the split-gesture model of timing in /pV/ sequences, see Tilsen’s (2017)Tilsen, S. (2017). Exertive modulation of speech and articulatory phasing. Journal of Phonetics, 62, 34-50. https://doi.org/10.1016/j.wocn.2017.03.001
electromagnetic articulographic study of unconditioned variation, in which six speakers repeated [ip^há] 400 times per session.

We adopt the split-gesture hypothesis but substitute the broader label target for closure, thereby generalizing the model to all consonantal constriction types, including plosives, fricatives, and approximants. The coupling graph in (7) defines a /CV/ demisyllable. Below the graph appears a hypothetical gestural score, in which consonantal and vowel gestures are displayed as arcs along two separate tiers, with the horizontal axis denoting time. To the right of the gestural score, we transcribe its hypothesized acoustic output.

Vowels are specified to have a longer duration than consonants. As indicated by the vertical broken line connecting the two dots in the gestural score, the beginning of the vowel is timed to coincide with the midpoint between the beginnings of the consonant’s target and release, which are symmetrically pushed apart in time.

Nam (2007c, pp. 500‒503)Nam, H. (2007c). Syllable-level intergestural timing model: Split-gesture dynamics focusing on positional asymmetry and moraic structure. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 483-506). De Gruyter Mouton.
argues that the split-gesture representation can also explain why, in syllable theory, onset consonants are typically weightless, while coda consonants can either bear their own mora or share one with the preceding vowel. In a /VC/ syllable rhyme, the vowel is coupled anti-phase with both the target and release of a non-moraic, weightless coda (8)a but only with the target of a moraic coda (8)b. Competitive coupling yields a degree of temporal compression of the target and release in speech planning that makes the consonant too short to contribute weight as an onset (7) or as a mora-sharing coda (8)a. Since they are not competitively coupled with the vowel, the target and release of a moraic coda (8)b are not under any pressure to begin at the same point in time, which allows the anti-phase coupling to produce a greater delay in the initiation of the release, effectively lengthening the consonantal constriction, i.e. [Cː].

4.2. Ambisyllabic shortening in NCPS

 ⌅

Because stress assignment in contemporary NCPS is arguably insensitive to syllable weight (Baković, 2016Baković, E. (2016). Exceptionality in Spanish stress. Catalan Journal of Linguistics, 15, Exceptions in Phonology, 9-25. https://doi.org/10.5565/rev/catjl.182
; Piñeros, 2016Piñeros, C. E. (2016). The phonological weight of Spanish syllables. In R. Núñez-Cedeño (Ed.), The syllable and stress: Studies in honor of James W. Harris (pp. 271-314). De Gruyter Mouton. https://doi.org/10.1515/9781614515975-011
), we assume that coda consonants in the language share a mora with the preceding vowel. This assumption makes it possible to combine the split-gesture representation of onsets (7) and weightless codas (8)a into a new dynamical representation of ambisyllabicity that naturally and correctly predicts the shortening of derived onsets discussed in Section 3. We argue that the target and release of a derived onset are competitively coupled anti-phase with the first vowel and in-phase with the second. Furthermore, the first vowel is coupled anti-phase to the second, across a word boundary. As illustrated in (9), the target and release are under twice as much pressure to begin at the same time. Logically, the oral constriction of the consonant will be subject to twice as much temporal compression as that of a canonical onset (7) or weightless coda (8)a alone. Greater compression in speech planning predicts a shorter constriction in the gestural score and the acoustic output, transcribed here as $\left[\breve{\mathrm{C}}\right]$ .

The gradient duration asymmetries among /V#s̺V/, /Vs̺V/, and /Vs̺#V/ contexts in Table 1 can now be theoretically predicted based on the combined effects of prosodic strengthening and multiple competitive couplings. The competitive coupling in (7) yields a baseline duration mean of 81.9 ms for word-medial canonical onset /s̺/. Prosodic word-initial strengthening increases the magnitude of the fricative’s target gesture, which gradiently lengthens the constriction duration up to a mean of 87.91 ms. At the right edge of a morphological word, multiple competitive couplings with the adjacent vowels in (9) increase the temporal compression of the fricative’s target and release, which shortens the constriction duration down to a mean of 76.23 ms. Gradient shortening follows neither from the fricative’s affiliation to two abstract syllable nodes, nor from its misalignment across prosodic word and syllable domains, but rather from the fact that its target and release gestures are competitively coupled to two vowels instead of just a single vowel.

4.3. Ambisyllabic lengthening in Italo-Romance and Standard Italian

 ⌅

Further support for the split-gesture model comes from Burroni’s (2022)Burroni, F. (2022). A split-gesture, competitive, coupled oscillator model of syllable structure predicts the emergence of edge gemination and degemination. Proceedings of the Society for Computation in Linguistics, Vol. 5, Article 3. https://doi.org/10.7275/wjq6-wm83
account of ambisyllabic consonant lengthening across morpheme boundaries in Central and Southern Italo-Romance varieties and Standard Italian. A process known as Raddoppiamento Sintattico derives word-initial geminate consonants in certain prosodic (10)a and morphological (10)b contexts. Furthermore, morpheme-final singleton codas in loanwords become geminates in suffixed forms (10)c and as derived onsets in word-final prevocalic position (10)d.

Building upon the computational approach of Nam (2007aNam, H. (2007a). A gestural coupling model of syllable structure. (Publication No. 3267328) [Doctoral dissertation, Yale University]. ProQuest Dissertations & Theses Global.
, 2007bNam, H. (2007b). Articulatory modeling of consonant release gesture. International Congress on Phonetic Sciences XVI. Germany. https://www.icphs2007.de/conference/Papers/1648/1648.pdf
, 2007c)Nam, H. (2007c). Syllable-level intergestural timing model: Split-gesture dynamics focusing on positional asymmetry and moraic structure. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 483-506). De Gruyter Mouton.
, Burroni carries out TaDA simulations that further support a split-gesture representation of /CV/ demisyllables (7) and also make possible a unified account of derived geminates, which are hypothesized to emerge across morpheme boundaries as a result of “changes in the dynamical coupling between the oscillator controlling the relative timing of CLO, REL, and V” (2022, p. 18Bradley, T. G., & Lozano, C. J. (2022). Language contact and phonological innovation in the voiced prepalatal obstruents of Judeo-Spanish. Languages 7(4), 313. https://doi.org/10.3390/languages7040313
). Specifically, the CLO of a word-initial onset loses its in-phase coupling with V₂ and becomes coupled anti-phase with V₁, and the REL of a word-final coda loses its anti-phase coupling with V₁ and becomes coupled in-phase with V₂. These symmetrical changes give rise to an ambisyllabic but non-competitively coupled split-gesture that is the same in word-initial and morpheme-final contexts (see Burroni’s Figures 7 and 9 on pp. 16‒17). We recreate this structure here, following the same format as in (7)‒(9) above:

In (11), the first vowel is coupled anti-phase with only the target, and only the release is coupled in-phase with the second vowel. Because they are not competitively coupled with V₁ and V₂, the target and release are pushed farther apart by their anti-phase coupling, thereby lengthening the consonantal constriction, as in the case of moraic codas (8)b.

In syllable theory, word-final derived onsets in NCPS (9) and edge geminates in Italo-Romance and Standard Italian (11) can be considered ambisyllabic, since in both cases, an intervocalic consonant belongs to two adjacent syllables simultaneously. However, ambisyllabicity itself makes no inherent predictions about consonantal shortening or lengthening. On the other hand, a split-gesture, coupled oscillator model of the syllable makes possible a principled account of the difference, which depends on the dynamical couplings among the consonant’s target and release gestures and the adjacent vowels. Competitive coupling predicts shortening (9), while non-competitive coupling predicts lengthening (11).

5. ACCOUNTING FOR CORONAL FRICATIVE LENITION

In doña Gregoria Canelo’s orthographic renditions of traditional CS speech (Catalán, 1954Catalán, D. (1954). Concepto lingüistico del dialecto ‘chinato’ en una chinato-hablante. Revista de dialectología y tradiciones populares. Consejo Superior de Investigaciones Científicas. https://en.calameo.com/books/00467782022819fecff5e
), <j> denotes a glottal fricative [h], and <d> denotes a voiced interdental continuant [ð] or its dental plosive allophone [d]. Canelo varies in her transcription of word-final intervocalic <d>, either attaching it to the following word, e.g. la dalaj for [lað álah] (3)a, or combining words without spaces, e.g. badamicada for [báð a mi káða] (3)b. An underappreciated observation about Canelo’s texts is that word-final fricatives are often transcribed as <j> followed by a space and then a word-initial <d>:

These examples correspond to NCPS casarnos este año, eres un confite and zarzas y las. While they may be transcription errors, Hualde (1991)Hualde, J. I. (1991). Aspiration and resyllabification in Chinato Spanish. Probus, 3(1), 55-76. https://doi.org/10.1515/prbs.1991.3.1.55
acknowledges that such forms “could be interpreted as instances of ambisyllabicity: word-final [ð] links to the following syllable without delinking from the coda position that it occupied” (p. 64, footnote 7). Based on the orthographic variation in (12), we assume that CS derived onsets were ambisyllabic, as in (9). This assumption leads to a novel account of coronal fricative lenition, as we next show.

5.2. A formal account of aspiration and voicing in CS

 ⌅

A standard assumption in the coupled oscillator model of the syllable is that intergestural coupling graphs are stored in the lexicon. Smith (2018)Smith, C. (2018). Harmony in gestural phonology. (Publication No. 10931524) [Doctoral dissertation, University of Southern California]. ProQuest Dissertations & Theses Global.
and Walker and Proctor (2019)Walker, R., & Proctor, M. (2019). The organisation and structure of rhotics in American English rhymes. Phonology, 36(3), 457-495. https://doi.org/10.1017/S0952675719000228
propose instead that gestural coupling is phonologically regulated by a constraint-based OT grammar. A single hierarchy of ranked constraints chooses the optimal coupling graph of an input utterance, which can then be phonetically implemented in TaDA as a gestural score. Some approaches to the phonetics-phonology interface postulate distinctive features in the lexicon and the phonology, which are then transduced into articulatory gestures in the phonetic component. The framework employed here gets closer to the original intent of AP by positing articulatory gestures as phonological primitives throughout the entire grammar, thereby obviating the need to map features onto gestures in the first place. From a representational point of view, there is, technically speaking, no phonetics-phonology interface, even if the grammar still distinguishes between optimization and implementation.

In our analysis, the optimal distribution of fricative gestures emerges from constraint interaction, and then gradient (de)voicing may arise in implementation under the influence of articulatory and aerodynamic factors, as discussed by Sedó et al. (2020)Sedó, B., Schmidt, L., & Willis, E. (2020). Rethinking the phonological process of /s/ voicing assimilation in Spanish: An acoustic comparison of three regional varieties. Studies in Hispanic and Lusophone Linguistics, 13(1), 167-217. https://doi.org/10.1515/shll-2020-2027
and Garellek et al. (2021)Garellek, M., Chai, Y., Huang, Y., & Van Doren, M. (2021). Voicing of glottal consonants and non-modal vowels. Journal of the International Phonetic Association, 1-28. https://doi.org/10.1017/S0025100321000116
. Table 2 gives the relevant gestural specifications for voiceless and voiced anterior coronal fricatives and for [H], which we use as a cover symbol for the glottal spreading gesture that is responsible for aspiration but that is not coupled to any oral gesture. Glottal [H] is distinct from the phonemic posterior fricative of many Andalusian and Latin American Spanish varieties, e.g. as in gente ‘people’, ajo ‘garlic’, which we assume to be a pharyngeal (Marrero, 1990, p. 377Marrero, V. (1990). Estudio acústico de la aspiración en español. Revista de filología española, 70(3/4), 345-397. https://doi.org/10.3989/rfe.1990.v70.i3/4.672
) and, therefore, oral gesture activating the Tongue Root articulator.

Table 2.  Constriction Degree (CD) specifications of the Tongue Tip and Glottis articulators for seven fricative gestures.

	θ, s̪, s̺	H	ð, z̪, z̺
Tongue Tip CD	[critical]	-	[critical]
Glottis CD	[wide]	[mid]	[narrow]

Constriction Degree (CD) is a phonetic continuum divided into discrete ranges, from most to least open: [wide], [mid], [narrow], [critical], and [closed] (Browman & Goldstein, 1989, p. 225Browman, C. P., & Goldstein, L. (1989). Articulatory gestures as phonological units. Phonology, 6(2), 201-251. https://doi.org/10.1017/S0952675700001019
). In coronal fricatives, a Tongue Tip CD [critical] gesture is responsible for generating turbulent noise in the oral cavity. In order to provide enough air flow to generate such noise (Solé, 2010Solé, M.-J. (2010). Effects of syllable position on sound change: An aerodynamic study of final fricative weakening. Journal of Phonetics, 38(2), 289-305. https://doi.org/10.1016/j.wocn.2010.02.001
), voiced fricatives require a larger glottal opening than the Glottis CD [critical] specification that Browman and Goldstein (1989, pp. 237‒239)Browman, C. P., & Goldstein, L. (1989). Articulatory gestures as phonological units. Phonology, 6(2), 201-251. https://doi.org/10.1017/S0952675700001019
posit as the default value for modally voiced plosives and sonorants. Table 2 situates three gestural classes along a Glottis CD continuum. The [mid] value of [H] is intermediate between the [wide] value of voiceless fricatives and the [narrow] value of voiced ones.

We take constriction duration to be the primary cue to an obstruent’s phonological voicing category: voiced obstruents are phonetically shorter than their voiceless counterparts (Katz, 2016, pp. 64‒66Katz, J. (2016). Lenition, perception and neutralisation. Phonology, 33(1), 43-85. https://doi.org/10.1017/S0952675716000038
). A contrast based on consonant duration is most perceptually distinctive between two vowels, which make it easier for the listener to identify the consonant’s beginning and ending points (for experimental evidence from a perception study, see Dmitrieva, 2018Dmitrieva, O. (2018). The role of perception in the typology of geminate consonants: Effects of manner of articulation, segmental environment, position, and stress. Language and Speech, 61, 43-57. https://doi.org/10.1177/0023830917696113
). Our analysis uses two faithfulness constraints. (13)a formalizes the intervocalic preference by enforcing faithfulness to the Glottis CD specification of an input gesture appearing in the following position: between two vowels that belong to the same morphological stem, without an intervening stem boundary. (13)b penalizes, in any context, an unfaithful mapping of any gesture (or set of gestures comprising the traditional phonological ‘segment’-see the discussion around (18) below). For example, /θ/→ð and /θ/→H each violate (13)b once, as do /ð/→θ, /ð/→H, /H/→θ, and /H/→ð.

Interacting with faithfulness are markedness constraints (14)a,b that penalize in-phase fricative-vowel couplings and (14)c‒e that penalize anti-phase couplings with a fricative:

The symbols S and Z denote voiceless and voiced Tongue Tip fricatives in Table 2, abstracting away from differences in the location of the constriction. These constraints assume the competitively coupled split-gesture model of consonants, as in NCPS (7) and (8)a. For visual simplicity, the constraint names collapse the target and release into one cover symbol, and a single line indicates the relevant competitive coupling relation. The two in-phase constraints exist in a stringency, or specific-to-general, relationship (de Lacy, 2004de Lacy, P. (2004). Markedness conflation in Optimality Theory. Phonology, 21(2), 145-199. https://doi.org/10.1017/S0952675704000193
), whereby candidates violating (14)a necessarily violate (14)b as well, but not vice versa. Stringency captures the relative harmony, or well-formedness, of onset fricatives, but without the need to posit a universally fixed constraint ranking. The fewer total violations of the two constraints, the more harmonic the onset fricative. For example, the demisyllable H―V violates both (14)a,b, ð―V only (14)b, and θ―V, neither. This predicts a universal scale of relative well-formedness for onset fricatives: θ―V > ð―V > H―V, where more harmonic gestural couplings appear to the left. By contrast, the anti-phase coupling constraints (14)c‒e are not stringently related. A candidate that violates one of the three anti-phase coupling constraints does not automatically violate either of the other two constraints.

Tableau (15) gives the analysis of stem-medial intervocalic and word-initial postpausal positions (2)a‒e, in which all three fricative gestures are considered as possible inputs. The forms under evaluation are idealized word shapes that represent only the phonological context that is relevant to the analysis. Output candidates for intervocalic position (15)a‒i omit the anti-phase coupling between vowels. *H―V eliminates (15)c,f,i,l,o,r, in which the glottal fricative appears as a canonical onset. Ranked above *{H,Z}―V, positional faithfulness maintains the voicing contrast between intervocalic /θ/ and /ð/ (15)a,e. However, positional faithfulness is irrelevant in word-initial contexts. The ranking of *{H,Z}―V above context-free faithfulness neutralizes the input /θ/‒/ð/‒/H/ contrast to [θ] (15)j,m,p. Postpausal and postnasal /d/ (2)f,g plausibly arose by a previous sound change, whereby listeners misperceived historical [dz] (or [ð]) as a non-sibilant plosive in fortition environments and subsequently restructured those lexemes with underlying /d/.

(15)	*H―V	Ident-GCD/ [ V_V St ]	*{H,Z}―V	Ident-(gesture)
a. /VθV/ V θ―V
b. V ð―V		*!	*	*
c. V H―V	*!	*!	*	*
d. /VðV/ V θ―V		*!		*
e. V ð―V			*
f. V H―V	*!	*!	*	*
g. /VHV/ V θ―V		*!		*
h. V ð―V		*!	*	*
i. V H―V	*!		*
j. /θV/ θ―V
k. ð―V			*	*
l. H―V	*!		*	*
m. /ðV/ θ―V				*
n. ð―V			*!
o. H―V	*!		*!	*
p. /HV/ θ―V				*
q. ð―V			*!	*
r. H―V	*!		*!

Anti-phase coupling constraints become relevant before a consonant (3)e,f and a pause (3)a,c. Tableau (16) includes only /θ/ in the input, shown in the upper-left cell, but the analysis still works assuming input /ð/ or /H/ instead. Positional faithfulness is irrelevant outside of the stem-medial intervocalic context. The ranking of *⇢H below *⇢S and *⇢Z chooses [H] as the optimal canonical coda fricative (16)c. Gradient devoicing of [H] in phonetic implementation follows from the subglottal pressure drop that naturally occurs at the end of an utterance (Garellek et al., 2021Garellek, M., Chai, Y., Huang, Y., & Van Doren, M. (2021). Voicing of glottal consonants and non-modal vowels. Journal of the International Phonetic Association, 1-28. https://doi.org/10.1017/S0025100321000116
; Sedó et al., 2020, p. 206Sedó, B., Schmidt, L., & Willis, E. (2020). Rethinking the phonological process of /s/ voicing assimilation in Spanish: An acoustic comparison of three regional varieties. Studies in Hispanic and Lusophone Linguistics, 13(1), 167-217. https://doi.org/10.1515/shll-2020-2027
). The complete loss of subglottal pressure can variably prevent turbulent noise from being generated across the glottis at all, e.g. [lað álah ~ lað ála].

(16) /Vθ#V/	*H―V	Ident-GCD/[ V_V St]	*⇢S	*{H,Z}―V	*⇢Z	*⇢H	Ident-(gesture)
a. V⇢θ			*!
b. V⇢ð					*!		*
c. V⇢H						*	*

In word-final prevocalic position (3)a,b, ambisyllabic coupling (9) activates both in-phase and anti-phase constraints. Output candidates in tableau (17) omit the anti-phase coupling between the two vowels. Even though the context is intervocalic, positional faithfulness is irrelevant because both vowels do not belong to the same morphological stem. The ranking of *⇢Z below *H―V and *⇢S chooses [ð] as the optimal derived onset (17)b.

(17) /Vθ#V/	*H―V	Ident-GCD/[ V_V St]	*⇢S	*{H,Z}―V	*⇢Z	*⇢H	Ident-(gesture)
a. V⇢θ―V			*!
b. V⇢ð―V				*	*		*
c. V⇢H―V	*!			*		*	*

In stem-final intervocalic contexts (3)c,d, the fricative contrast is neutralized to voiced [ð]. Our analysis makes use of a morphologically sensitive markedness constraint on the coupling of gestures within the consonant. In AP, a distinction can be made between primary and secondary constriction gestures, which together comprise the traditional phonological ‘segment’ (Gafos, 2002, p. 284Gafos, A. I. (2002). A grammar of gestural coordination. Natural Language and Linguistic Theory 20, 269-337. https://doi.org/10.1023/A:1014942312445
; Proctor, 2011Proctor, M. 2011. Towards a gestural characterization of liquids: Evidence from Spanish and Russian. Laboratory Phonology, 2(2), 451-485. https://doi.org/10.1515/labphon.2011.017
; Smith, 2018, pp. 22‒24Smith, C. (2018). Harmony in gestural phonology. (Publication No. 10931524) [Doctoral dissertation, University of Southern California]. ProQuest Dissertations & Theses Global.
). The primary constriction of a consonant includes its anti-phased target and release gestures (Nam 2007aNam, H. (2007a). A gestural coupling model of syllable structure. (Publication No. 3267328) [Doctoral dissertation, Yale University]. ProQuest Dissertations & Theses Global.
, 2007bNam, H. (2007b). Articulatory modeling of consonant release gesture. International Congress on Phonetic Sciences XVI. Germany. https://www.icphs2007.de/conference/Papers/1648/1648.pdf
, 2007cNam, H. (2007c). Syllable-level intergestural timing model: Split-gesture dynamics focusing on positional asymmetry and moraic structure. In J. Cole & J. I. Hualde, J. (Eds.), Laboratory Phonology 9 (pp. 483-506). De Gruyter Mouton.
). The secondary constriction depends on the consonant’s manner of articulation, i.e. a Tongue Body, Velum or Glottis gesture for liquids, nasals, and voiceless obstruents, respectively. We assume secondary constrictions are not split into separate target and release and that they are coupled to the target gesture of the primary constriction.

Given these assumptions, we propose a markedness constraint that penalizes the intra-segmental, in-phase coupling of a secondary Glottis CD [wide] gesture to a primary Tongue Tip gesture at the right edge of a morphological stem, irrespective of the primary gesture’s Constriction Degree or Location:

Rather than a universal constraint, (18) can be understood as a phonotactic restriction that is particular to the morphology of CS. As such, the constraint is not automatically projected by learners of other language varieties. In the CS grammar, (18) outranks *{H,Z}―V, thereby optimizing syllable-initial [ð] in stem-final prevocalic contexts. Although few if any words in the native CS lexicon end in /t/, (18) would predict voicing in stem-final prevocalic contexts, e.g. in loanwords or neologisms with final /t/. In phonetic implementation, the resulting output [d] gesture would be realized as a continuant [ð] as the result of gestural undershoot in phrase-medial postvocalic contexts (Parrell, 2011Parrell, B. (2011). Dynamical account of how /b, d, g/ differ from /p, t, k/ in Spanish: Evidence from labials. Laboratory Phonology, 2(2), 423-449. https://doi.org/10.1515/labphon.2011.016
). For plural forms whose corresponding singulars end in a consonant, it must be assumed, pace Bermúdez-Otero (2006Bermúdez-Otero, R. (2006). Morphological structure and phonological domains in Spanish denominal derivation. In F. Martínez-Gil & S. Colina (Eds.), Optimality-theoretic studies in Spanish phonology (pp. 278-311). John Benjamins. https://doi.org/10.1075/la.99
, 2013)Bermúdez-Otero, R. (2013). The Spanish lexicon stores stems with theme vowels, not roots with inflectional class features. Probus, 25(1), 3-103. https://doi.org/10.1515/probus-2013-0009
, that the /e/ of the final syllable is not a suffixal allomorph of the null stem formative Ø but instead appears outside the stem, either as the result of phonological epenthesis (Colina, 2006Colina, S. (2006). Optimality-theoretic advances in our understanding of Spanish syllable structure. In F. Martínez-Gil & S. Colina (Eds.), Optimality-theoretic studies in Spanish phonology (pp. 172-204). John Benjamins. https://doi.org/10.1075/la.99.08col
; Moyna & Wiltshire, 2001Moyna, I., & Wiltshire, C. (2001). Spanish plurals: Why [s] isn’t always optimal. In H. Campos, E. Herburger, A. Morales-Front, & T. J. Walsh (Eds.), Proceedings of the 3rd Hispanic Linguistics Symposium (pp. 31-48). Cascadilla Press.
; Wiltshire, 2020, p. 322Wiltshire, C. (2020). Plural formation and gender allomorphy. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 307-324). Routledge. https://doi.org/10.4324/9781315228112
) or as part of a lexically listed allomorph of the plural suffix (Saporta, 1965, p. 220Saporta, S. (1965). Ordered rules, dialect differences, and historical processes. Language, 41, 218-224. https://doi.org/10.2307/411875
):

The stem boundary deactivates positional faithfulness and activates (18), which together ensure stem-final intervocalic [ð].

The Hasse diagram in (20) summarizes the complete constraint ranking for CS. Vertical lines connect higher-ranking constraints to the lower-ranking constraints they dominate. Unconnected constraints do not directly conflict.

6. RHOTIC NEUTRALIZATION IN DERIVED ONSETS

The patterning of word- and prefix-final prevocalic rhotic consonants in Spanish seems to provide further evidence that resyllabification must be complete. To indicate syllable boundaries, we add periods to the following examples, which are drawn from Hualde’s (2014, pp. 181‒185)Hualde, J. I. & Prieto, P. (2014). Lenition of intervocalic alveolar fricatives in Catalan and Spanish. Phonetica, 71(2), 109-127. https://doi.org/10.1159/000368197
description of NCPS:

There is a phonological contrast between an apicoalveolar tap /ɾ/ and trill /r/ in stem-medial intervocalic position, where both rhotics syllabify as single onsets, e.g. caro vs. carro (21)a. In the syllable rhyme, neutralization results in non-contrastive variation between the tap and trill, e.g. dar (21)b. Outside of the stem-medial context, the pronunciation of an intervocalic rhotic signals its morphological affiliation. For example, the trill is necessarily word-initial in the two-word phrase da rocas (21)c and stem-initial in the prefixed form extra-rápido (21)d, while the tap is necessarily word-final in dar ocas (21)e and prefix-final in super-ávido (21)f.

In a foundational rule-based account of Spanish rhotics, Harris (1983Harris, J. (1983). Syllable structure and stress in Spanish: A non-linear analysis. The MIT Press. https://archive.org/details/syllablestructur00harr
, 2001Harris, J. (2001). Reflections on a phonological grammar of Spanish. In J. Herschensohn, E. Mallén, & K. Zagona (Eds.), Features and interfaces in Romance: Essays in honor of Heles Contreras (pp. 133-145). John Benjamins. https://doi.org/10.1075/cilt.222.09har
, 2002)Harris, J. (2002). Flaps, trills, and syllable structure in Spanish. In A. Csirmaz, Z. Li, A. Nevins, O. Vaysman, & M. Wagner (Eds.), Phonological answers: MIT Working Papers in Linguistics 42 (pp. 81-108). Department of Linguistics, MIT.
argues that the stem-medial intervocalic contrast in (21)a is represented phonologically as a difference between a singleton /ɾ/ and its geminate counterpart /ɾɾ/. A lexical rule strengthens onset /ɾ/ to a trill [r] after a consonant in the preceding syllable rhyme (e.g. honra ‘honor’, alrededor ‘around’, Israel ‘Israel’) and is followed by a postlexical rule of coda /ɾ/-deletion before [r]. Together, these two rules derive an intervocalic singleton onset trill from the underlying stem-medial geminate /ɾɾ/, e.g. /kaɾɾo/ → káɾ.ɾo → káɾ.ro → [ká.ro]. On the other hand, strengthening in the syllable rhyme (21)b is an optional rule of emphatic speech, which Harris assigns to the postlexical phonology, ordered to apply after resyllabification. In addition to the rule of postconsonantal strengthening mentioned above, the analysis requires a separate rule of stem-initial /ɾ/ strengthening to account for the contexts in (21)c,d. For Hualde (1989, p. 824)Hualde, J. I. (1989). Silabeo y estructura morfémica en español. Hispania, 72(4), 821-831. https://doi.org/10.2307/343560
, stem-initial strengthening is an obligatory, early cyclic rule of the lexical phonology.

The crucial argument for complete resyllabification comes from the contexts in (21)e,f. Harris’s ordering of optional rhyme strengthening after postlexical resyllabification explains the prohibition against prevocalic [r] at the right edge of a word or prefix. At the point in the derivation when emphatic strengthening could apply, the taps in question are no longer in the syllable rhyme, having already resyllabified into the following onset. Because emphatic strengthening could still apply if such taps were to maintain their lexical affiliation to the preceding rhyme, resyllabification must be assumed to be complete.

Bradley’s (2020)Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
monostratal OT account of the NCPS rhotic distribution turns out to be entirely compatible with an ambisyllabic representation of incomplete resyllabification. The analysis uses a perceptually-based markedness constraint on consonant duration contrast and two markedness constraints on the in-phase coupling of tap and trill gestures with a following vowel. Grounded in previous work on rhotics in Spanish (Bradley, 2005bBradley, T. G. (2005b). Systemic markedness and phonetic detail in phonology. In R. Gess & E. Rubin (Eds.), Experimental and theoretical approaches to Romance linguistics (pp. 41-62). John Benjamins. https://doi.org/10.1075/cilt.272.04bra
, 2006bBradley, T. G. (2006b). Spanish rhotics and Dominican hypercorrect /s/. Probus, 18, 1-33. https://doi.org/10.1515/PROBUS.2006.001
) and Catalan (Padgett, 2009Padgett, J. (2009). Systemic contrast and Catalan rhotics. The Linguistic Review, 26, 431-463. https://doi.org/10.1515/tlir.2009.016
) within the constraint-based Dispersion Theory of Contrast (Flemming, 2004Flemming. E. (2004). Contrast and perceptual distinctiveness. In B. Hayes, R. Kirchner, & D. Steriade (Eds.), Phonetically-based phonology (pp. 232-276). Cambridge University Press. https://doi.org/10.1017/CBO9780511486401.008
), (22) rules out a surface contrast between the relatively shorter tap [ɾ] and the relatively longer trill [r] in any position that is not stem-medial intervocalic:

Bradley (2020, p. 247)Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
initially relativized this constraint to the prosodic word domain. In keeping with the positional faithfulness constraint (13)a, the updated constraint (22) is relativized to the morphological stem domain. The definition is functionally motivated by Dmitrieva’s (2018)Dmitrieva, O. (2018). The role of perception in the typology of geminate consonants: Effects of manner of articulation, segmental environment, position, and stress. Language and Speech, 61, 43-57. https://doi.org/10.1177/0023830917696113
experimentally supported claim that differences in consonant duration are easiest to hear in the context of two surrounding vowels.

The analysis requires only two markedness constraints on in-phase coupling:

(23)a is violated whenever [ɾ] and a following vowel are coupled exclusively in-phase while belonging to the same morphological stem domain.⁵(23)a is inactive on /CɾV/ demisyllables because the in-phase ɾ―V coupling is not exclusive but, instead, competitive with the in-phase C―V coupling. For further discussion of complex onsets and syllable-initial postpausal and postconsonantal contexts, which are not treated here, see Bradley (2020, pp. 243‒249). (23)b is more general, penalizing the in-phase coupling of [r] with a following vowel in any morphological context.

Tableau (24) gives an analysis of rhotic contrast and neutralization across six contexts:

(24)	Space-Dur/[V_V St]	Ident-(gesture)	*[ɾ―V St]	*r―V
/VɾV1 VrV2/
a. V ɾ―V1 V r―V2			*	*
b. V ɾ―V1,2		*!	*
c. V r―V1,2		*!		*
/Vɾ1 Vr2/
d. V⇢ɾ1 V⇢r2	*!
e. V⇢ɾ1,2		*
f. V⇢r1,2		*
/V#ɾV1 V#rV2/
g. V ɾ―V1 V r―V2	*!		*	*
h. V ɾ―V1,2		*	*!
i. V r―V1,2		*		*
/V+ɾV1 V+rV2/
j. V ɾ―V1 V r―V2	*!		*	*
k. V ɾ―V1,2		*	*!
l. V r―V1,2		*		*
/Vɾ#V1 Vr#V2/
m. V⇢ɾ―V1 V⇢r―V2	*!			*
n. V⇢ɾ―V1,2		*
o. V⇢r―V1,2		*		*!
/Vɾ+V1 Vr+V2/
p. V ɾ―V1 V r―V2	*!			*
q. V ɾ―V1,2		*
r. V r―V1,2		*		*!

Within each context, the input contains two highly idealized words or phrases, each tagged with its own subscript. These shapes stand in for actual words or phrases from the language’s lexicon but also represent phonological contexts in loanwords or neologisms. The analysis systematically considers three output candidates: (i) contrast between the tap and trill, (ii) neutralization to the tap, and (iii) neutralization to the trill. Combined subscripts indicate neutralization, or the merger of two words or phrases in the output. The ranking of Ident-(gesture) above the constraints on intergestural coupling predicts a tap/trill contrast in stem-medial intervocalic position (24)a, which corresponds to the existing minimal pair in (21)a, among others. Attempting a tap/trill contrast in any other context fatally violates perceptual spacing, as seen in (24)d,g,j,m,p. In each case, the two remaining neutralization candidates are tied on their faithfulness violations, which passes the decision down to the lower-ranking gestural coupling constraints. Since they refer specifically to in-phase coupling, *[ ɾ―V_Stem] and *r―V are inactive on rhotics that are coupled only anti-phase with a preceding vowel. The analysis predicts free variation between co-optimal (24)e,f, which corresponds to the non-contrastive variation observed in (21)b. Further gradient weakening can occur in the phonetic implementation of [ɾ] and [r] in this and other contexts (see Bradley, 2020, pp. 251‒253Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
).

To understand the evaluation of candidates (24)g‒r, it helps to consider the morphological representations of examples (21)c‒f:

The ranking of *[ ɾ―V_Stem] above *r―V eliminates candidates (24)h,k, in which [ɾ] and the following vowel are coupled in-phase while belonging to the same morphological stem. Because their violations of lower-ranking *r―V are tolerated, candidates (24)i,l emerge as optimal, predicting neutralization to stem-initial [r] in (25)a,b. Although intervocalic word-/prefix-final [ɾ] is coupled in-phase with a following vowel, this vowel does not belong to the same morphological stem as the rhotic. Therefore, *[ ɾ―V_Stem] is inactive on syllable-initial [ɾ] in both word-final (24)m,n and prefix-final (24)p,q contexts. Because they satisfy the only remaining constraint in the hierarchy *r―V, candidates (24)n,q emerge as optimal, predicting neutralization to [ɾ] in (25)c,d.

Bradley (2020, pp. 246‒251)Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
originally relativized *[ ɾ―V_Stem] to the morphological word domain. However, the constraint *[ ɾ―V_MWd] incorrectly excludes syllable-initial [ɾ] from the context in (25)d because the rhotic and the following vowel still belong to the same MWd domain, thereby overgenerating *supe[r]-ávido. Relativized instead to the morphological stem, *[ ɾ―V_Stem] becomes inactive in prefix-final prevocalic contexts, which correctly allows *r―V to favor syllable-initial [ɾ], as shown in (24)q.

Another piece of evidence that the morphological stem is the correct domain of *[ ɾ―V_Stem] comes from plural forms of rhotic-final singular nominals. An apparent restriction in the morphology of NCPS is that the nominal class of Ø-stems does not include roots that end in a trill /r/. Harris (1969, p. 51Harris, J. (1969). Spanish phonology. The MIT Press. https://archive.org/details/spanishphonology00jame/page/n1/mode/2up
, 1983, p. 69Harris, J. (1983). Syllable structure and stress in Spanish: A non-linear analysis. The MIT Press. https://archive.org/details/syllablestructur00harr
, 2002, p. 96)Harris, J. (2001). Reflections on a phonological grammar of Spanish. In J. Herschensohn, E. Mallén, & K. Zagona (Eds.), Features and interfaces in Romance: Essays in honor of Heles Contreras (pp. 133-145). John Benjamins. https://doi.org/10.1075/cilt.222.09har
interprets the lack of singular-plural alternations, e.g. flo[ɾ] ~ *flo[r]es ‘flower ~ flowers’ as evidence that a root-final trill is an underlying geminate tap /ɾɾ/. A final /e/ allows the geminate in /toɾɾe/ torre ‘tower’, as well as the root-final cluster in /kaɾne/ carne ‘meat’, to be properly syllabified. However, Baković (2009, p. 9)Baković, E. (2009). Abstractness and motivation in phonological theory. Studies in Hispanic and Lusophone Linguistics, 2, 183-198. https://doi.org/10.1515/shll-2009-1041
counters that positing a geminate interpretation is no better motivated than defining the relevant stems in terms of permissible final consonants. Other singleton consonants like /t/ must be excluded from this set, e.g. /bote/ bote ‘boat’ vs. */bot/, and a singleton trill /r/ would need to be excluded as well. An explanation for this morphological gap falls out naturally from our analysis, without the need to assume a geminate tap /ɾɾ/ in a language that otherwise lacks true geminate consonants. In line with (19)a, we postulate [[floɾ_Stem] es̺_MWd] as the morphological representation of the plural form flores, which allows us to invoke the same analysis that accounts for prefix-final prevocalic rhotics. Because the surrounding vowels do not belong to the same stem, the perceptual spacing constraint prevents a tap/trill contrast and forces neutralization. Because the /e/ of the plural suffix does not belong to the same stem as the rhotic, *[ ɾ―V_Stem] becomes irrelevant, thereby allowing *r―V to eliminate the trill in favor of the tap in the syllable onset, as in prefix-final prevocalic position (24)q.

Crucially, our analysis is able to ensure neutralization to morpheme-final prevocalic [ɾ] independently of how the rhotic is actually syllabified. Whether the rhotic is coupled ambisyllabically with both surrounding vowels (24)n or coupled only in-phase with the following vowel (24)q, it is the presence of a morphological stem boundary that crucially triggers a violation of Space-Dur/[ V_V_Stem] and also renders *[ ɾ―V_Stem] inactive. Alternative accounts of optional emphatic strengthening posit a rule (Harris, 1983Harris, J. (1983). Syllable structure and stress in Spanish: A non-linear analysis. The MIT Press. https://archive.org/details/syllablestructur00harr
, 2001Harris, J. (2001). Reflections on a phonological grammar of Spanish. In J. Herschensohn, E. Mallén, & K. Zagona (Eds.), Features and interfaces in Romance: Essays in honor of Heles Contreras (pp. 133-145). John Benjamins. https://doi.org/10.1075/cilt.222.09har
, 2002)Harris, J. (2002). Flaps, trills, and syllable structure in Spanish. In A. Csirmaz, Z. Li, A. Nevins, O. Vaysman, & M. Wagner (Eds.), Phonological answers: MIT Working Papers in Linguistics 42 (pp. 81-108). Department of Linguistics, MIT.
or markedness constraint (Colina, 2009Colina, S. (2009). Spanish phonology: A syllabic perspective. Georgetown University Press.
, 2010Colina, S. (2010). Rhotics in Spanish: A new look at an old problem. In C. Borgonovo, M. Español-Echevarría, & P. Prévost (Eds.), Selected Proceedings of the 12th Hispanic Linguistics Symposium (pp. 75-86). Cascadilla Proceedings Project. https://www.lingref.com, document #2407.
; Roca, 2005Roca, I. (2005). Strata, yes; structure preservation, no. Evidence from Spanish. In T. Geerts, I. van Ginneken, & H. Jacobs (Eds.), Romance Languages and Linguistic Theory 2003: Selected Papers from ‘Going Romance’ 2003, Nijmegegen, 20-22 November (pp. 197-218). John Benjamins. https://doi.org/10.1075/cilt.270.12roc
) targeting individual rhotics in the syllable rhyme. Because it uses only in-phase coupling constraints *[ ɾ―V_Stem] and *r―V, our analysis does not have to worry about overgenerating a trill [r] when coupled anti-phase with a preceding vowel in ambisyllabic environments. Derived onset rhotics can be ambisyllabic (24)n, as long as gestural coupling constraints target only the in-phase coupling of a rhotic with a following vowel.

7. CONCLUSION

The main goal of this article has been to reconcile two opposing claims about the status of resyllabification in the Spanish phonology literature. On the one hand, a classic generative analysis of coronal fricative lenition in CS has long provided a compelling theoretical argument in favor of complete resyllabification (Section 2). On the other hand, recent experimental studies of NCPS have uncovered gradient phonetic differences in voicing and duration between derived and canonical onset /s̺/ (Section 3), which suggests that, at least for some speakers in laboratory speech, the structural difference between the two categories is incompletely neutralized. An explanatory phonological representation of the difference has remained elusive, until now.

Our approach to resolving these contradictory findings has been to start with insights from studies based on computational articulatory simulations (Section 4.1), which led us to propose a novel, competitively coupled split-gesture representation of ambisyllabic consonant shortening in AP (Section 4.2). We then showed how such a phonetically-based representation predicts the behavior of derived onset /s̺/ in NCPS and, with minimal changes in dynamical couplings, is further supported by Burroni’s (2022) Burroni, F. (2022). A split-gesture, competitive, coupled oscillator model of syllable structure predicts the emergence of edge gemination and degemination. Proceedings of the Society for Computation in Linguistics, Vol. 5, Article 3. https://doi.org/10.7275/wjq6-wm83
TaDA simulations of the opposite phenomenon of ambisyllabic lengthening in Italo-Romance and Standard Italian (Section 4.3). Ambisyllabic gestural coupling then provided a simpler approach to coronal fricative weakening in CS and other varieties of contemporary Spanish, couched within monostratal, parallel OT, without ordered levels or strata, intermediate forms, or output-output faithfulness (Section 5).

As we demonstrated in Section 6, it is no longer necessary to assume complete resyllabification of prefix- and word-final prevocalic consonants in order to account for obligatory neutralization to [ɾ] in these contexts, pace Harris (1983Harris, J. (1983). Syllable structure and stress in Spanish: A non-linear analysis. The MIT Press. https://archive.org/details/syllablestructur00harr
, 2001Harris, J. (2001). Reflections on a phonological grammar of Spanish. In J. Herschensohn, E. Mallén, & K. Zagona (Eds.), Features and interfaces in Romance: Essays in honor of Heles Contreras (pp. 133-145). John Benjamins. https://doi.org/10.1075/cilt.222.09har
, 2002)Harris, J. (2002). Flaps, trills, and syllable structure in Spanish. In A. Csirmaz, Z. Li, A. Nevins, O. Vaysman, & M. Wagner (Eds.), Phonological answers: MIT Working Papers in Linguistics 42 (pp. 81-108). Department of Linguistics, MIT.
. Henceforth, this pattern can be better understood as supporting our claim that in Spanish phonology, a perceptually-based markedness constraint restricts the rhotic duration contrast to stem-medial intervocalic position and that there is no rule or markedness constraint targeting individual taps or trills in the syllable rhyme. Both the aspiration of coda obstruents in CS and the emphatic strengthening of coda /ɾ/ in NCPS are compatible with incomplete resyllabification, represented as ambisyllabic gestural coupling, which in turn supports our definition of markedness constraints (14) and (23) on intergestural coupling.

The present study invites further laboratory and theoretical research. The mathematical implications of ambisyllabic competitive coupling for the shorter duration of the oral constriction of derived onsets in NCPS still need to be verified by explicit computational modeling in TaDA, following Burroni’s (2022)Burroni, F. (2022). A split-gesture, competitive, coupled oscillator model of syllable structure predicts the emergence of edge gemination and degemination. Proceedings of the Society for Computation in Linguistics, Vol. 5, Article 3. https://doi.org/10.7275/wjq6-wm83
account of Italo-Romance. There is also a need for phonetic studies of resyllabification in varieties other than NCPS, using different consonants and experimental methodologies.⁶Initial work along these lines, with speakers of Latin American Spanish, has been presented by Beristain (2021), based on nasal airflow data, and Repiso-Puigdelliura (2021), based on acoustic duration measurements with a range of word-final coronal consonants. Using a lexical decision experiment, Lahoz-Bengoechea and Jiménez-Bravo (2021) found that NCPS listeners can perceptually distinguish between canonical and derived onset /s̺/ and /n/ (but not /l/) based on gradient, synthetically manipulated differences in consonant duration. Lahoz-Bengoechea and Jiménez-Bravo also describe derived onsets as ambisyllabic, but they do not discuss Nam’s split-gesture hypothesis nor the link between competitive coupling and temporal compression, as predicted by our representation in (9). Finally, more work within the grammatical architecture employed here is necessary to explore the implications of ambisyllabic coupling for modeling other well-known segmental coda alternations of Spanish phonology, e.g. nasal velarization and liquid vocalization, and in a wider range of morphophonological contexts, i.e. prefixation and compounding.

Our analysis further supports a grammatical approach to the phonetics-phonology interface that does not require any transduction of distinctive features into articulatory gestures (Bradley, 2020Bradley, T. G. (2020). Spanish rhotics and the phonetics-phonology interface. In S. Colina & F. Martínez-Gil (Eds.), The Routledge handbook of Spanish phonology (pp. 237-258). Routledge. https://doi.org/10.4324/9781315228112
; Smith, 2018Smith, C. (2018). Harmony in gestural phonology. (Publication No. 10931524) [Doctoral dissertation, University of Southern California]. ProQuest Dissertations & Theses Global.
; Walker & Proctor, 2019Walker, R., & Proctor, M. (2019). The organisation and structure of rhotics in American English rhymes. Phonology, 36(3), 457-495. https://doi.org/10.1017/S0952675719000228
). Rather, the intergestural coupling graph of an utterance is phonologically optimized by OT constraint interaction and then phonetically implemented, where gestural overlap and reduction and universal aerodynamic principles further shape the speech output. In terms of the architecture of the grammar, phonology and phonetics are derivationally ordered components, but they nonetheless operate on the same representational primitives, namely intergestural coupling graphs.