ArticlePDF Available

Spectral properties of anterior sibilant fricatives in Northern Peninsular Spanish and sibilant-merging and non-merging varieties of Basque


Abstract and Figures

This paper focuses on the spectral properties of anterior sibilant fricatives in Northern Peninsular Spanish, and sibilant-merging and non-merging varieties of Basque. Non-merging varieties of Basque have two voiceless anterior sibilant fricatives, characterized as apico-alveolar and lamino-alveolar. In other Basque varieties, however, these two phonemes have merged with varying results. Twenty-four participants divided into four different groups have been studied. One group is a set of monolingual Spanish speakers from north-central Spain while the remaining three are Basque-Spanish bilingual groups with different sibilant fricative systems in Basque. The goal is to describe the spectral properties of anterior sibilant fricatives and examine the effect of the L1-Basque sibilant system upon L2-Spanish. The Basque varieties chosen are (1)-Azpeitia Basque, where merging in favor of the lamino-alveolar sibilant fricative has occurred, (2)-Lemoa Basque, where the merging in favor of the apico-alveolar sibilant fricative is widespread, and (3)-Goizueta Basque, where no merging has happened. Participants took part in an elicitation task where they produced sentences containing target words with an intervocalic anterior sibilant fricative in Basque and Spanish. Bayesian probability was used for inferential statistics. Speakers of the non-merging Basque variety show the narrowest acoustic dispersion of /s/ in Spanish, as opposed to broader diffusion in the other three groups. Regarding L1 transfer, while the Azpeitia group does not show transfer into Spanish, the Lemoa and Goizueta groups do. Results show that /s/ is more fronted for monolingual Spanish speakers from north-central Spain than what previous literature has reported.
Content may be subject to copyright.
Spectral properties of anterior sibilant fricatives in Northern Peninsular Spanish and
sibilant-merging and non-merging varieties of Basque
Ander Beristain
University of Illinois at Urbana-Champaign
This paper focuses on the spectral properties of anterior sibilant fricatives in Northern
Peninsular Spanish, and sibilant-merging and non-merging varieties of Basque. Non-merging
varieties of Basque have two voiceless anterior sibilant fricatives, characterized as apico-
alveolar and lamino-alveolar. In other Basque varieties, however, these two phonemes have
merged with varying results. Twenty-four participants divided into four different groups have
been studied. One group is a set of monolingual Spanish speakers from north-central Spain
while the remaining three are Basque-Spanish bilingual groups with different sibilant fricative
systems in Basque. The goal is to describe the spectral properties of anterior sibilant fricatives
and examine the effect of the L1-Basque sibilant system upon L2-Spanish. The Basque varieties
chosen are (1)-Azpeitia Basque, where merging in favor of the lamino-alveolar sibilant fricative
has occurred, (2)-Lemoa Basque, where the merging in favor of the apico-alveolar sibilant
fricative is widespread, and (3)-Goizueta Basque, where no merging has happened. Participants
took part in an elicitation task where they produced sentences containing target words with an
intervocalic anterior sibilant fricative in Basque and Spanish. Bayesian probability was used for
inferential statistics. Speakers of the non-merging Basque variety show the narrowest acoustic
dispersion of /s/ in Spanish, as opposed to broader diffusion in the other three groups.
Regarding L1 transfer, while the Azpeitia group does not show transfer into Spanish, the Lemoa
and Goizueta groups do. Results show that /s/ is more fronted for monolingual Spanish speakers
from north-central Spain than what previous literature has reported.
1. Introduction
Linguists have long been interested in studying sibilant sounds in languages as the acoustic and
spectral properties presented in these sounds pose many interesting questions. According to the
World Atlas of Language Structures (Dryer & Haspelmath 2013), although most languages have
sibilant fricatives or affricates, the number of these sounds within each language is not usually
large. According to Maddieson (1984, as cited by Maddieson 1997), out of the 453 languages he
studied, 80% of them have a type of /s/ in their phonetic inventory. The place of articulation
(PoA) of these fricatives is, generally, either dental or alveolar (Mielke 2018: 140). Maddieson
(2014) maintains these results, where more than 500 languages have been studied already. For
instance, that is the case for Northern Peninsular Spanish (NPS), which has an alveolar fricative
/s/ and a post-alveolar affricate /tʃ/.
In this study, we examine the realization of sibilants in two languages in contact, Basque
and Spanish (the NPS variety, specifically), which show different sibilant systems in their
phonetic inventories. As just mentioned, NPS has two sibilant sounds, the voiceless alveolar
fricative /s/, as in casa [kása] ‘house’, and the voiceless post-alveolar affricate /tʃ/, as in cacha
[káʧa] ‘handle piece’. It is worth mentioning that NPS also has an interdental fricative phoneme
/θ/, as in caza [káθa] ‘hunting’.
This article is under the Journal of the International Phonetic
Association copyright and the publisher should be contacted for
permission to re-use or reprint the material in any form. This version is
a Submitted Manuscript Under Review (previous to the Accepted
Manuscript) where the information of the author has been added.
Beristain, A. (in press). Spectral properties of anterior sibilant fricatives in Northern Peninsular Spanish and sibilant-merging and non-
merging varieties of Basque. Journal of the International Phonetic Association.
On the other hand, conservative varieties of Basque show a rich system of six sibilants of
which three are fricative and the remaining three are affricate. All sibilant sounds in conservative
varieties of Basque are voiceless. Table 1 shows the sibilant phonemes in conservative varieties
of Basque with their respective features, orthographic representations, and examples within
Table 1. Sibilant system of conservative varieties of Basque (adapted from Beristain 2018a: 70)
Place of
Manner of
Nonetheless, this system of sibilant sounds is not the norm for most Basque varieties. In
many other dialects of Basque, mergers have occurred, reducing the number of sibilants in their
phonetic inventories. In this regard, Basque shows different patterns regarding fricative and
affricate sibilants.
As far as sibilant fricatives are concerned, most neutralizing varieties have merged the
two alveolar phonemes in favor of the apico-alveolar /s
̺/, a neutralization process known as seseo
(Iribar & Isasi 2008). Zuazo (2014) points out that this process appears in Biscay (western
Basque Country), Araba (southwestern Basque Country), and some areas of Gipuzkoa (central
Basque Country).
However, neutralization of alveolar sibilant fricatives in favor of the lamino-alveolar /s
is also present in more geographically restricted areas in Gipuzkoa. Hualde (2010) mentions that
the varieties spoken in the towns of Azpeitia and Azkoitia are representative of this process,
which is called zezeo (Hualde 2010, Beristain 2018b, 2019). Hualde (2010) also explains that it
has taken place since the 17th century. In El borracho burlado, a play written by Xabier Munibe
(1764), resident of Azkoitia and a speaker of that town’s variety, there are some instances of
zezeo. For example, the sentence in Basque ezango diote ‘they will say that to him’ (Munibe
1764: 32) shows a <z> where there should be an <s>. This leads us to think the use of <s> and
<z> was not clear because of the merger of such sounds.
In addition, although not so prevalent, the process of xexeo happens in Basque varieties in
contact with French (Hualde 2010: 101). In those varieties, the sibilant fricative inventory
includes the lamino-alveolar /s
̻/ and post-alveolar /ʃ/ sibilants. The apico-alveolar sibilant /s
̺/ has
merged with /ʃ/ in favor of the latter.
There has been neutralization with affricates as well. Yet, it has only been in one
direction, namely the apico-alveolar /ts
̺/ with the lamino-alveolar /ts
̻/ in favor of the latter (/ts
̺/ →
̻]; e.g. atso ‘old woman’, atzo ‘yesterday’, both pronounced as [ats
̻o] in neutralizing varieties).
This process is called tzetzeo (Gaminde et al. 2013, Beristain 2018a). All Biscayan varieties and
several Gipuzkoan ones have undergone this process. However, although not so prevalent,
txetxeo (merging of /tʃ/ and /ts
̻/ in favor of [tʃ]), also occurs in some areas of Gipuzkoa (Hualde
2010: 98). As a reviewer points out, remarkably, no varieties of Basque have been found to
merge the affricate sibilants in favor of the apico-alveolar one (*/ʦ
̻/ → [ts
̺]; e.g., atso ‘old
woman’, atzo ‘yesterday’, both pronounced as [ats
̺o]), and, therefore, the most common pattern
for the neutralization with affricates is the least common one with fricatives.
This study explores how bilingual Basque/Spanish speakers from different dialectal areas
of the Basque Country produce anterior sibilant fricatives in Spanish and Basque. This study will
compare the bilingual production of native speakers of three Basque varieties with different
sibilant fricative systems: (1) Lemoa Basque, a variety where seseo has occurred; (2) Azpeitia
Basque, a variety where zezeo is prevalent; and (3) Goizueta Basque, a conservative variety
where the canonical system of Basque sibilants is maintained. Due to the absence of non-anterior
sibilant fricative phonemes in NPS, i.e., the post-alveolar /ʃ/ phoneme, the present paper will
focus on anterior sibilants.
In addition, we will also consider the effect of having several versus one anterior sibilant
fricative(s) in Basque on the acoustic dispersion of /s/ in Spanish. In Flemming’s (2017)
Dispersion Theory, dispersion relates to how extensively the data distribution is stretched.
Linguistic transfer will be examined via Flege’s (1995) Speech Learning Model, which states
that mapping two different sound categories between two similar sounds in the first language
(L1) and second language (L2) will be a daunting task.
The present paper starts by presenting research questions and predictions. Next, a review
of the literature concerning the production of sibilants in Basque and Spanish is provided. Then,
the study’s methodology is presented. Finally, results, a discussion, and concluding remarks
assessing support for hypotheses are given.
2. Research questions and predictions
An important prediction that Flemming’s (2017) Dispersion Theory makes is that the degree of
diffusion in phonetic realization of a given phoneme will be limited when there is a phonemic
neighbor. Furthermore, Flege’s (1995) Speech Learning Model predicts that L2 learners will
accommodate the production of similar L2 sounds to those in the L1. Based on these theoretical
claims, the present study intends to answer the following research questions (RQs):
RQ1: Is the /s/ of monolingual Spanish speakers more acoustically dispersed than the /s/
in Spanish of Basque speakers? If so, does having contrastive phonemic neighbors in Basque
have an effect?
Prediction 1: Yes, it is expected that monolingual Spanish speakers’ acoustic
dispersion of /s/ will be more diffused than that of Basque speakers who have the
phonemic contrast between /s
̺/ and /s
̻/ (non-merging speakers).
Prediction 2: Within Basque varieties, those with a merger should show similar
results to those of monolingual Spanish speakers, since only one anterior sibilant is
kept in the Basque sibilant system and there is no neighboring phonemic contrast.
RQ2: Do Basque speakers transfer Basque /s
̺/ to Spanish /s/?
Prediction 1: Yes, speakers of varieties that show the apico-alveolar phoneme /s
̺/ in
their phonological inventories will transfer that sound onto Spanish /s/. This is due to
strong similarity between the two sounds.
Prediction 2: No, speakers of varieties that neutralize anterior sibilant fricatives in
favor of the lamino-alveolar /s
̻/ will not transfer that sound into Spanish /s/ due to
acoustic dissimilarity between /s
̻/ and the canonical /s/ in Northern Peninsular
Spanish. These speakers should be able to map a new sound category. It is expected
that the production of the new sound should show a less fronted place of articulation
(PoA) as opposed to Basque /s
RQ3: Is the realization of Spanish /s/ by Basque-Spanish bilingual speakers comparable
to that of monolingual Spanish speakers?
Considering that Basque /s
̺/ is described to be more acoustically and articulatorily similar
to /s/ in Northern Peninsular Spanish (NPS) than Basque /s
̻/ is, the prediction is the following:
Prediction 1: Speakers of Basque varieties that have /s
̺/ in their phonological
inventory should produce Spanish /s/ in a way that resembles the production of
monolingual Spanish speakers more than Basque speakers of varieties that only have
the lamino-alveolar sibilant fricative /s
3. Literature review
3.1. Theoretical framework
3.1.1. Paradigm
This study is situated within the cognitivist paradigm. ‘Cognitive aspects of second language
acquisition […] seek to identify the mental processes that are implicated in learning and using a
second language’ (Bialystok 1994: 158). This study will analyze the influence that the L1 of
bilingual speakers might have on the production of their L2. More specifically, the two
languages under study are Basque (as L1) and Spanish (as L2).
Previous research has attempted to answer a) whether bilingual speakers have an L1-L2
intermingled phonological system or whether they have two different sub-systems (Etxebarria
1997, Bosch & Sebastián-Gallés 2001, Flege 2002, 2007, Sebastián-Gallés & Bosch 2002, Flege,
Schirru & MacKay 2003); and b) whether, in bilingual environments, L2 sound discrimination is
more native-like in production (Flege 1995) or perception (Best 2001). This study will aim to
advance what is known about the former question. It will further study the contact effects
between Basque and Spanish and whether L1-Basque L2-Spanish bilingual speakers are able to
produce small L1-L2 phonetic differences.
3.1.2. Bilingualism and sound production
A model that tests L2 phonological acquisition is the Ontogeny and Phylogeny model (Major
2001). This model predicts that minor differences between L1-L2 sounds will result in a slow
linguistic development. Minor differences include those that are not so easily perceivable, such
as the difference between the PoA of English /t/ and /d/ and Spanish /t
̪/ and /d
̪/. Whereas these
phonemes are alveolar in English, they are dento-alveolar in Spanish. The subtle difference in
production (and perception) complicates their acquisition. Indeed, the variable under study in the
present paper falls into this category. Yárnoz (2001: 58), citing Navarro Tomas (1923),
summarized the differences between Spanish /s/ and Basque /s
̺/ as follows:
The rounded tongue tip is pointed in Spanish, the convex pre-dorsum in Basque is
concave in Spanish, the apico-alveolar narrowness is more open in Basque, the
PoA is more retracted in Basque, and the position of the tongue is a little more
palatalized than in the Spanish /s/ as a consequence of the greater lingual surface
in contact with the palate.
Flege’s (1995) Speech Learning Model (SLM) makes the claim that the sound inventory
of the L1 influences the production of the L2 in specific ways. If an L2 sound does not appear in
the L1 inventory (i.e., new sound), mapping a new sound category should not be complicated for
a learner. This is due to the fact that there is not a near phonemic category in the L1 phonological
inventory. However, if the distinct L1 and L2 sounds are similar to one another (i.e., similar
sound), the speaker might find it more complicated to map two different phonemic categories,
and the L2 sound will assimilate to that of the L1. The latter situation applies to the present
study, as NPS /s/ and Basque /s
̺/ are extremely similar to one another. It could be expected that
Spanish /s/ will assimilate to Basque /s
Another aspect to consider is the fact that while NPS has one sibilant fricative in its
phonetic inventory, conservative varieties of Basque have three. Flemming’s (2017) Dispersion
Theory posits that the dispersion degree of the phonetic realization of a particular phoneme will
be narrower when there is another phoneme in the phonological inventory that shares several
phonetic and phonological features with it. In other words, the acoustic diffusion of a given
phoneme will be narrower when there is a near phonological neighbor. Thus, it could be
expected that the acoustic dispersion of /s/ in Spanish as produced by Spanish L1 speakers will
be greater than that of both the Spanish /s/ and the Basque /s
̺/ of speakers of conservative
varieties of Basque, which have two other sibilant fricatives in their inventory, i.e., the lamino-
alveolar /s
̻/ and the post-alveolar /ʃ/. Gaminde et al. (2013) also proposed this hypothesis while
studying the realization of affricates in the Western Basque dialect.
In sum, having considered all these theoretical claims, it can be expected that L1-Basque
speakers that have an apico-alveolar sibilant fricative in their inventories will assimilate the /s/ in
Spanish to /s
̺/ in Basque. Nonetheless, for speakers who do not have an apical sibilant in Basque,
but, rather, only a lamino-alveolar one, it should be easier to produce the /s/ sound in Spanish in
a similar way to monolingual speakers of this language, mapping it to a new phoneme category,
since their native Basque sibilant is sufficiently distant from NPS /s/.
3.2. Previous work on Basque and Spanish sibilants
After Navarro Tomás’s (1923) claim, several studies have attempted to investigate whether
Basque speakers maintain their Basque /s
̺/ realization for Spanish /s/. According to previous
descriptions by Navarro Tomás (1923) and Yárnoz (2001), these phonemes have slightly
different phonetic realizations in the two languages, but empirical evidence from several studies
on the matter provide conflicting results.
Elejabeitia & Bizcarrondo (1992) (as cited by Paasch-Kaiser 2013: 48) conducted a
transcriptional and acoustic study and interviewed 22 students at the University of Deusto in
Bilbao (the capital of Biscay). Half of them were Basque-Spanish bilingual speakers, whereas
the other half were monolingual Spanish speakers. When the researchers analyzed the
productions of the sibilant fricative /s/ in Spanish by inspecting the spectrograms, the researchers
deduced that the Basque-Spanish bilingual group’s Spanish /s/ showed acoustic features of the
Basque apico-alveolar /s
̺/. The researchers also state they did not find any instances of lamino-
alveolar sibilant fricative productions for Spanish /s/ in their corpus. It needs to be mentioned
that neither did the researchers control the participants’ dialectal areas nor did they provide a
description of the participants’ origins.
Iribar et al. (2005) analyzed the production of /s/ in Spanish by a group of Basque-
dominant speakers in Lekeitio, a town in Biscay. It should be noted that in the Basque variety
spoken in Lekeitio, anterior sibilant fricatives are merged in favor of /s
̺/. They wanted to
investigate whether the productions of /s
̺/, /s
̻/, and /s/ were cross-linguistically shared between
Basque and Spanish. They tested a small number of participants (n = 2). Speakers had to produce
70 words. The first 30 words were Spanish words with orthographic <s>, the next 20 were
Basque words with orthographic <s>, and the last 20 were Basque words with orthographic <z>.
The authors analyzed the mean intensity of the consonant, which was also further divided into
three equal parts along the first 8 kHz of the spectrum, and the initial frication point for each
sibilant (idem: 3). They analyzed the aforementioned variables because (a) intensity is correlated
with the degree of energy of the air expelled, where the greater the oral constriction is, the lower
the intensity values are; (b) research had shown that the frequency range of Basque sibilants
reaches up to 8 kHz; and (c) the initial frication point was believed to be correlated with the
sibilants’ spectral peaks (and PoA), where the lower the initial frication point is, the more
retracted the PoA is, too(
). After observing the intensity values of the Basque and Spanish
anterior sibilants, the researchers concluded that the merger of the three sibilants was evident
since the difference in intensity and frequencies between the three sound categories was almost
Iribar & Túrrez (2015) carried out a more extensive study that encompassed several
dialectal areas. They included 15 participants who had had little exposure to Spanish throughout
their lives. The researchers wanted to determine whether these speakers had been able to develop
a different target for Spanish /s/. They included several acoustic measurements in their analysis:
(a) mean frequencies, where the higher the value, the more fronted the PoA of the sibilant is; (b)
intensities of the first three spectral peaks, and the start point of frication (see previous
paragraph); and (c) bandwidths of the first three spectral peaks, where a lower and more fronted
tongue position is correlated, respectively, with higher F1 and F2 values, and lower F3 values
have usually been associated with lip rounding (Lindblom & Sundberg 1971, Fant 1992, as cited
by Lawson, Stuart-Smith & Rodger 2019: 4365). Examining the results, Iribar & Túrrez found
that speakers showed practically identical results for the acoustic realizations of the Basque
anterior sibilant fricative phonemes and the Spanish one. If speakers showed the lamino-alveolar
̻/ phoneme in Basque, they showed higher spectral peaks and F1 values, which would correlate
with the PoA of the sibilant and the lower position of the tongue while producing the lamino-
alveolar sibilant. As in the previous study, the results were practically identical for these
speakers’ Spanish. However, if a speaker did not have the lamino-alveolar /s
̻/ phoneme but the
apico-alveolar /s
̺/ in Basque, spectral peaks were lower and the F1 and F2 values were lower too,
indicating that the tongue showed a more elevated and retracted position in the oral cavity. Once
again, this type of speaker showed almost identical results between their neutralized Basque
sibilants in favor of /s
̺/ and Spanish /s/. Iribar & Túrrez (2015: 231) also point out ‘a few difficult
cases to explain’, where a speaker did not have a lamino-alveolar /s
̻/ phoneme in Basque, but
when producing /s/ in Spanish, they showed acoustic properties of the phoneme /s
̻/ produced by
speakers who had it. Nevertheless, it is important to consider that these researchers only tested
participants with little exposure to Spanish. Nowadays, the degree of bilingualism is higher in the
Basque Country, and younger speakers start having contact with Spanish from an early age at
Jurado (2011) conducted an extensive study of Basque sibilant fricatives and the
production of /s/ in the Spanish variety of the Basque Country. She focused on the north-central
part of the Basque Country, specifically the Donostialdea and Bidasoa counties of Gipuzkoa.
Within the Bidasoa county, only participants from Irun were selected. These areas were chosen
because they exemplify conservative varieties of Basque. A total of 24 participants were
recruited. The researcher divided the participants into three groups: (1) monolingual Spanish
speakers, (2) Basque-Spanish bilingual speakers whose L1 was Basque, and (3) Basque-Spanish
bilingual speakers whose L1 was Spanish. She utilized several dependent variables to examine
the PoA of sibilants: (a) F2 values at the initial point of the sibilant, expecting lower F2 values
for the lamino-alveolar /s
̻/ phoneme since the position of the tongue is lower than for the apico-
alveolar /s
̺/ phoneme; (b) intensity (see previous paragraphs); (c) frequency cut-off, which shows
the lowest frequency at which energy is concentrated, and according to Ladefoged & Maddieson
(1996), as cited by Jurado (2011: 103), the bigger the length of the vocal tract downstream of the
constriction is, the lower the frequency cut-off will be; (d) center of gravity (CoG), which has
been correlated with the PoA of sibilants showing lower values for a more retracted PoA, and
higher values for a more fronted PoA; and (e) spectral peaks (see previous paragraphs).
According to her results, Basque-Spanish bilingual speakers whose L1 was Basque did not have
three clear phonetic targets for Basque /s
̺/, /s
̻/ and Spanish /s/. These speakers only had two
realizations, one for Basque /s
̻/ and one for the two apico-alveolar phonemes. Against her initial
predictions, Basque-Spanish bilinguals whose L1 was Spanish showed lower CoG values for the
production of Basque /s
̺/ and Spanish /s/ as opposed to the /s/ produced by monolingual Spanish
speakers. This would imply that even if Spanish was their L1, the influence of Basque /s
̺/ was
still present in the production of Spanish /s/ in the Spanish variety of the Basque Country.
Segura (2014) studied the production and perception of Basque sibilants by L1 Spanish
speakers with different degrees of proficiency in Basque. According to her production results,
the degree of proficiency did not significantly affect the results. As mentioned by one reviewer,
the author found that speakers produced the lamino-alveolar sibilant /s
̻/ in a more posterior
region than what is reported in the literature, and thus their pronunciation is closer to that of the
apico-alveolar sibilant /s
Larraza, Samuel & Oñederra (2016a) examined the effect of dialectal variation on the
discrimination of Basque sibilant fricatives. They tested the discrimination of sibilant fricatives
in speakers from a merging variety and a non-merging variety. Their results show that speakers
who had a merger in their variety had lower accuracy scores in a discrimination task and higher
response times as opposed to speakers who had a contrast between the two alveolar sibilant
fricatives in Basque. This indicates that the lack of the contrast in their native phonological
inventory complicated the correct discrimination.
In a different study, Larraza, Samuel & Oñederra (2016b) compared the discrimination of
Basque alveolar sibilants by Basque-Spanish (simultaneous, early, and late) bilinguals and
Basque-French (simultaneous and early) bilinguals. According to their results, late Basque-
Spanish bilinguals (L1 Spanish, L2 Basque) showed lower accuracy scores and higher response
times in the critical condition, i.e., /s
̻/, as opposed to the other two Basque-Spanish bilinguals.
In the case of Basque-French bilinguals, the difference between control and critical pairs was not
prevalent. Furthermore, early bilinguals showed higher response times than simultaneous
Basque-French bilinguals. However, they also showed slightly higher accuracy scores than
simultaneous bilinguals, showing lack of correlation between the two parameters.
3.3. Acoustic parameters for the classification of sibilants
Most recent acoustic studies conducted on sibilant fricatives have turned to the study of the
spectral moments of these sounds (Jongman, Wayland & Wong 2000, Nissen & Fox 2005,
among others). The four spectral moments of sibilant sounds are identified with the four typical
statistical measures of a random distribution (mean, standard deviation, skewness, and kurtosis).
This study will include the analysis of the first two spectral moments, which are commonly
known as the CENTER OF GRAVITY of the energy (henceforth, CoG, see e.g. Boersma 2002), also
called ‘centroid’, and the VARIANCE, also called the ‘standard deviation’ (henceforth, SD).
Several studies have determined the apparent relationship between the PoA of fricatives
and the CoG value (Jongman et al., 2000). The general correspondence is that the more retracted
the PoA, the lower the CoG value. For instance, Jongman et al. (2000) determined the difference
between English /s/ and /ʃ/, and showed that the CoG of /s/ (6133 Hz) was higher than English /ʃ/
(4229 Hz).
Other authors have opted for using SPECTRAL PEAK as the variable under study (Reidy
2016). The main reason for that is that peak frequency has been found to correlate more strongly
than CoG with speakers’ perceptual prototypes (Newman, Clouse & Burnham 2001, Newman
2003). The correlation between the spectral peak with PoA is similar to that of CoG and PoA. As
observed in Johnson (2011: 130), the higher the spectral peak, the more fronted the PoA.
However, according to literature, both spectral peak and CoG can serve to yield accuracy with
respect to the PoA of the phoneme being produced (Li, Edwards & Beckman 2009). Since CoG
has shown to be an accurate variable to use to determine the PoA of a sibilant phoneme, this is
the measurement that will be used in this study (see Jesus & Shadle 2002 for a different
4. Methodology
4.1. Sampling
A total of 24 female participants were recruited in this study. With a small sample size, it was
thought it would be sensible to limit the speakers to one gender, and this would help to preserve
normal distribution in the data. All participants had received college education at the time of the
experiment, and none of the participants reported any history of speech, language, or hearing
disorders. Participants were further divided into four different groups. Serving as control, six
Spanish monolingual speakers were elected for Group 1 (n = 6). These speakers were from the
Valladolid-Burgos area, a north-central area in Spain. The remaining three groups were Basque-
Spanish bilingual groups. These groups were chosen because they represent different scenarios
of phonemic contrast in Basque sibilant fricatives. Group 2, from Azpeitia (in the Urola Valley
of central Gipuzkoa), merges the two alveolar phonemes in favor of the lamino-alveolar /s
̻/ (n =
6). Group 3, from Lemoa (in the Arratia Valley of southwestern Biscay), merges the two alveolar
sibilant fricatives in favor of the apico-alveolar /s
̺/ (n = 6). Group 4, from Goizueta (in
northwestern Navarre), represents a conservative non-sibilant-merging variety of Basque (n = 6).
Table 2 summarizes the main information regarding groups, and Figure 1 shows a map of the
Basque Country with its dialectal areas where the three towns under study have been marked.
Table 2. Participants and their backgrounds
Number of
(N = 24)
in L1
(northern Spain)
Azpeitia (Gipuzkoa)
Lemoa (Biscay)
Goizueta (Navarre)
̺, s
Figure 1. Basque varieties under study, L: Lemoa, A: Azpeitia, G: Goizueta (retrieved from
Zuazo 2019 with author’s permission)
The Basque varieties of Azpeitia, Lemoa, and Goizueta Basque have been previously
studied with respect to other linguistic matters such as accentual systems (Hualde 1997), verbal
morphology (Yrizar 1991, 1992, 2008), and lexical usage. Several dialectological studies
mention Azpeitia Basque (Bonaparte 1869, Yrizar 1991), but only a few studies in recent years
have attempted to give a more detailed phonological description of it (Hualde & Beristain 2017,
2018, 2019, 2020, Beristain 2018b, 2019). As far as Lemoa Basque is concerned, Gaminde
(2002) and Gaminde et al. (2013) have contributed to better understanding the phonological
processes arising in varieties in that area. Dialectological descriptions of Goizueta Basque have
been given in Zubiri & Perurena (1998) and Zubiri (2000). A phonological analysis of this
variety in the format of an Illustration of the IPA was published in Hualde, Lujanbio & Zubiri
(2010). Lujanbio’s (2016) doctoral dissertation examines linguistic variation within this town.
There are also a number of studies concerned with the pitch accent system of Goizueta Basque
including Hualde & Lujanbio (2008), Hualde, Lujanbio & Torreira (2008), Hualde & Beristain
(2018), and Lujanbio (2018). Nonetheless, no study focusing on sibilants in three participant
samples with different sibilant systems has been previously conducted, and this project will aim
at addressing this gap in research.
4.2. Data collection
Two production experiments were conducted. One of the experiments involved eliciting Basque
data and the other one involved Spanish data. For obvious reasons, Spanish monolingual
speakers only participated in the experiment that involved eliciting Spanish data. Half of the
speakers in each of the three Basque groups produced Spanish first, and then Basque, whereas
the rest first produced Basque and then Spanish. The assignment of the order type was
randomized. This experimental variable was included in order to determine whether language
order could have an effect on the production of sibilants.(
Participants in this study were recorded reading sentences in Basque and/or Spanish. The
target sentences were read from PowerPoint slides shown in a 13-inch MacBook Pro Retina
Display, 2015 model laptop. A MicroTrack 24/96 recording machine and a SONY F-720
external microphone were used to collect the data. The frequency range of the microphone was
50-13,000 Hz. The sampling rate was 44,100 Hz. The researcher held the microphone
approximately 10 cm (almost 4 inches) away from the participants’ mouths. All recordings took
place in a quiet room in the participants’ respective towns.
In target words, the quality of vowels preceding and following /s/ in Spanish, and /s
̺/ and
̻/ in Basque was controlled. The first condition was that the second vowel is always a vowel in
the periphery of the vowel space, i.e., a corner vowel /a, i, u/. Regarding the preceding vowel, it
has been shown that vowels producing distinct coarticulatory effects affect CoG measurements
differently. For example, Fujisaki & Kunisaki (1978) found that the [+round] feature of the
vowel /u/ lowered the mean frequencies of /s/ in Japanese. Taking this possible effect into
account, the most frequently occurring combinations in V1SV2 (where V2 is a corner vowel) in
Beristain’s (2018b, 2019) corpus were considered. This corpus is a dialectological dictionary of
Azpeitia Basque that includes a thorough phonological description of the variety and almost
3,000 lexical entries of every-day use. Thus, the list of the considered environments for the
sibilant to appear both in Basque and Spanish is the following one: /a_a, a_i, a_u, e_a, u_i/. It
needs to be mentioned that the most important factor is the following vowel (V2) because the
sibilant and V2 are in the same syllable.
Jurado (2011) and Muxika-Loitzate (2017) point out that the presence or absence of stress
on the syllable where the sibilant appears has an effect on the CoG, having higher CoG values
when the syllable is stressed. In the Spanish experiment in this study, the stress of the syllable
was controlled. However, because of dialectal variation with respect to stress location in Basque
varieties and inter-speaker variation within each variety it could not be controlled in Basque.
Thus, regarding the total number of tokens per speaker, monolingual Spanish speakers
produced (1 sibilant) x (2 V2-stress conditions) x (3 V2 conditions per stress condition, /a/: 4
words, /i/: 4 words, /u/: 2 words) x (2 repetitions) = 40 tokens per speaker, x 6 speakers = 240
tokens. The number of tokens produced in Spanish per group was the same. In total, then, there
were 240 tokens x 4 groups = 960 tokens. With respect to the Basque experiment, the number of
tokens per speaker is the following: (2 sibilants, /s
̺, s
̻/) x (3 V2 conditions, s
̺ (/a/: 9 words, /i/: 7
words, /u/: 4 words) and s
̻ (/a/: 8 words, /i/: 8 words, /u/: 4 words)) x (2 repetitions) = 80 tokens
per speaker, x 6 speakers per group = 480 tokens, x 3 groups in total = 1,440 tokens in Basque.
Therefore, the total number of tokens considering the two languages is 2,400. The list of words
produced in Spanish and Basque are included in APPENDIX A and APPENDIX B, respectively.
Participants were asked to read a list of target words put into context. They read the
carrier phrase I said TARGET in Spanish and I/She said TARGET in Basque. In the case of Spanish,
the stimulus sentence was Digo TARGET + additional phrase; and in the case of Basque, in order
to accommodate to the participants’ native varieties, the stimulus sentences appeared in the
regional variety. Since the number of tokens to be produced was twice as many as in Spanish, the
decision was made to vary the subject of the sentence in some occasions so that the task would
not feel so repetitive. Note that Basque is a pro-drop language and therefore the natural tendency
is to drop subject pronouns. The grammatical information appears in the auxiliary verb after the
main verb, which in the present study is esan ‘to say’. In the case of Azpeitia Basque, the
stimulus sentence was TARGET esan det/du, for I/She respectively; for Goizueta Basque, it was
TARGET san dut/du; and for Lemoa Basque, the stimulus sentence was TARGET esaot (< esan dot)
/esan dau. The standard Basque form would be esan dut/du.
4.3. Data analysis
The variables of interest in this experiment are the first and second spectral moments of sibilant
fricatives, i.e., the CoG and SD. The original control variables were the PHONEME (levels:
Spanish /s/, Basque /s
̺/, Basque /s
̻/), ORDER of experiments (levels: Spanish-Basque, Basque-
Spanish), preceding vowel (V1) (levels: /a, e, u/), following vowel (V2) (levels: /a, i, u/), and
STRESS OF SYLLABLE (levels: stressed, unstressed). An intercept for WORD was included and a
random slope for PHONEME within SPEAKER was included (contemplating the fact that some
speakers might merge the two Basque phonemes).
The realizations of Spanish /s/ and Basque /s
̺/, and /s
̻/ were analyzed via Praat (Boersma
& Weenink 2019). Different criteria were employed to segment sibilants from neighboring
vowels: a) inspection of the acoustic properties of the waveform (sibilants under study show
aperiodic waves as opposed to periodic ones in vowels); and b) inspection of the spectrum
(voiceless sibilant fricatives show no f0 due to the lack of wave periodicity as opposed to vowels
showing f0). Figures 2, 3, 4 show an illustration of the waveform, spectrogram, f0, and
segmentations for each phonemic sound under study.
Figure 2. Segmentation of the target word ‘Digo así con ganas’ ['I say “like this” eagerly’] (in
Spanish) by Castilian Speaker 5
Freq (Hz)
F0 (Hz)
Digo así con ganas
Time (s)
Figure 3. Segmentation of the target word ‘hasi san du’ ['She said to start’] (in Basque) by
Goizueta Speaker 30
Freq (Hz)
F0 (Hz)
hasi san du
Time (s)
Figure 4. Segmentation of the target word ‘hazi san du’ ['She said to grow’] (in Basque) by
Goizueta Speaker 30
Next, using a script that was specifically written for this project, values for CoG and SD
of the fricative were obtained in Praat. The signal was not pre-emphasized. Even if all sibilants
under study are voiceless, they appear in intervocalic contexts. In order to avoid coarticulatory
effects of voicing, two filters were applied: first, a high pass filter was applied to remove energy
below 550 Hz (Henriksen & Harper 2016, Chodroff 2017). Second, the initial 5% and final 5%
of the sibilant spectrum were not considered for the extraction of CoG and SD in order to reduce
any coarticulatory effects.
Once the data were coded, Bayesian mixed-effects linear regression models were built
under the package brms (Bürkner 2017) in R (R Core Team 2019) to determine the predictability
of the variables. In order to visualize the results in R, the ggplot2 package was employed
(Wickham 2016). The reason why Bayesian inference was used, as opposed to conventional
frequentist analyses, is that since part of the study involves mergers in specific varieties, some
speakers might not show any mergers while some others do. Frequentist analyses rely on single
points as means or medians, and having different kinds of speakers could alter the baseline for
inferential statistics. Bayesian analysis does not rely on single points to draw on inferential
conclusions. It adds previously known information (called priors) into the statistical model. The
output will return a lower-level and upper-level credible interval (CrI), which will provide a
Freq (Hz)
F0 (Hz)
hazi san du
Time (s)
range of interest of the variable being studied (Vasishth et al. 2018). Priors utilized for Bayesian
inference in this study were weakly informative ones. This is because there is not extensive
research that has shown clear values of CoG and SD of sibilants in Basque and Spanish.
Priors for Basque sibilants were obtained from Hualde (2010: 94), who provides CoG and
SD results for a speaker from the same non-merging variety that is studied in this project, i.e.,
Goizueta Basque (Table 3):
Table 3. Basque priors (from Hualde 2010: 94)
CoG (Hz)
SD (Hz)
<s> /s
<z> /
Priors for Spanish were obtained from Cicres (2011: 42) who studied the acoustic
production of different Peninsular Spanish fricatives. He studied six speakers, and obtained
individualized results for each fricative he studied. This project will use the mean value for /s/
from all these speakers as priors (Table 4):
Table 4. Spanish priors (from Cicres 2011: 42)
CoG (Hz)
SD (Hz)
A leave-one-out (LOO) validation was used to obtain the optimal statistical model (see
Vehtari, Gelman & Gabry 2017). In this method, a data point is left out, and after running the
model, the model itself is used to predict that data point and calculate the difference between the
predicted and actual value. The model that will fit the dataset best is that which has the lowest
LOO score.
In order to answer each RQ, different statistical models were created. Below are the
formulae and explanations of the structure of each model:
RQ1 (acoustic diffusion of /s/ in Spanish per variety):
Statistical model: brm(stdev ~ Variety + (1|Speaker) + (1|Word), data =
SpanishData, family = gaussian(), prior = priors_sp_stdev, iter = 2000, chains =
4, warmup = 1000, control = list(adapt_delta = 0.99))
RQ2 (L1-Basque transfer):
Statistical model (one per Basque variety): brm(cogfilt ~ Phoneme +
(Phoneme|Speaker) + (1|word), data = VarietyData, family = gaussian(), prior =
priors_spbq_cog, iter = 2000, chains = 4, warmup = 1000, control =
list(adapt_delta = 0.99))
RQ3 (Monolingual Spanish /s/ = X Basque variety’s /s/):
Statistical model: brm(cogfilt ~ Variety + (1|Speaker)+ (1|word), data =
SpanishData, family = gaussian(), prior = priors_sp_cog, iter = 2000, chains =
4, warmup = 1000, control = list(adapt_delta = 0.99))
The first and third statistical models have the same structure except for the dependent
variable. The model for RQ1 has the SD of the sibilant as the dependent variable since the
acoustic diffusion of the sibilant is examined. The model for RQ3 has CoG as its dependent
variable since the similarity in PoA is examined. VARIETY was included as the fixed factor and
random intercepts for WORD and SPEAKER were included. VARIETY refers both to monolingual
Spanish speakers and to bilingual speakers from the three Basque varieties. The Castilian variety
was set as the intercept since RQs are formulated as comparisons between what participants in
Basque-Spanish bilingual groups do as opposed to the Castilian group. Priors only include the
Spanish data for RQ1 and RQ3.
The statistical model for RQ2 includes both Basque and Spanish data. Since it is
understood that each Basque-Spanish bilingual group is independent from one another, a
separate model was created per group rather than creating an interaction between PHONEME and
VARIETY. A random intercept was included for WORD. In order to contemplate possible mergers
in Basque participants, a random slope was included of PHONEME within SPEAKER. The phoneme
̺/ was set as the intercept. This allows for the possibility to compare its production as opposed
to that of /s
̻/ in Basque (indicating whether there is a merger in that variety of Basque or not) and
/s/ in Spanish (showing whether participants transfer Basque /s
̺/ into Spanish /s/). Priors include
both Basque and Spanish data for RQ2.
It should also be noted that Bayesian analysis will not return p-values, but a CrI range
from where probabilistic conclusions will be drawn. The model output can be interpreted the
same way as a dummy-coded linear mixed-effects regression model, i.e., every level will return
the difference from the intercept. If the 95% CrIs cross the zero mark, then is deduced that,
probabilistically speaking, there will not be any differences between the two elements that are
being compared. If the 95% CrI does not cross the value of zero, then it is deduced that there is
little probability(
) where the comparison of the two elements equals zero, and therefore it is
deduced that they are different.
5. Results
5.1. RQ1: Acoustic diffusion of /s/ in Spanish
The Goizueta group (non-merging variety) showed the lowest SD of all groups. Mean and
standard deviation values are shown in Table 5(
). These results are plotted in Figure 5.
Table 5. SD mean (and its standard deviation) of /s/ in Spanish per variety (in Hz)
2565 (636)
2841 (637)
2585 (499)
2098 (491)
Figure 5. SD of /s/ in Spanish per variety (in Hz). [The white dot is the mean, the horizontal
black line in the middle is the median; the box represents the interquartile range (IQR);
vertical lines represent the dispersion of the data and are never 1.5 times the IQR; single
black data points are outliers that fall outside this range.]
As expected, sibilant-merging Basque varieties show more dispersed acoustic
productions of /s/ in Spanish than the non-merging variety. Notice the narrowness of the
dispersion of /s/ in the Goizueta group (the non-merging variety) as opposed to the other groups.
In order to examine the statistical significance of the results, the output of the model will
be observed. Table 6 shows a summary of the model output for the SD of /s/ in Spanish per
Table 6. Summary of Bayesian model output for the SD of /s/ in Spanish per group
Lower CrI
Upper CrI
Intercept: Castilian
Azpeitia (/s
Lemoa (/s
Goizueta (non-merging)
Speaker: random effect
Word: random effect
As can be observed in the output of the model, the Goizueta group (the non-merging
variety of Basque) is the only group that does not cross the zero mark (Est. = -460.23, SE =
194.01, l-95% CrI = -778.18, u-95% CrI = -141.18). The Azpeitia and Lemoa groups cross the
zero mark, which probabilistically speaking means that they behave as the intercept (the
Castilian group).
5.2. RQ2: L1-Basque influence on Spanish
In order to examine the influence of L1 Basque on Spanish, CoG values were observed in both
languages. Table 7 shows a summary of those results, and Figure 6 provides a visual
representation of those results.
Table 7. Mean CoG (and its standard deviation) values per sound category and group (in Hz)
7450 (1152)
6005 (725)
7914 (918)
7160 (987)
5925 (704)
5117 (308)
6745 (952)
5636 (713)
5193 (390)
Figure 6. Basque and Spanish sibilants by Basque-Spanish bilinguals
As previously stated, a different statistical model was built per Basque variety in order to
examine whether there is (1) a merger in that Basque variety, and (2) transfer from Basque to
5.2.1. Azpeitia (/s
̻/-merging variety):
As can be seen in Figure 7, there is great overlap between the three sibilants in the
Azpeitia group. That is, these Basque data would coincide with what previous literature has said,
i.e., there is a merging in this Basque variety as far as the apical fricatives are concerned.
Examining the means of the sibilants produced by the Azpeitia group, which are around 7000
Hz, it can be inferred that the merger is in favor of the lamino-alveolar sibilant fricative.
Figure 7. CoG of sibilants in the Azpeitia group. [A density plot could be described as a
smoother version of a histogram, and it marks the local density of points along the x-axis;
where data points occur more frequently, the density will be greater, thus showing peaks.]
Nevertheless, it is worthy of mention that Basque /s
̺/ and Spanish /s/ show bimodality for
this group of speakers. This is more evident for the production of Spanish /s/. Some participants
show lower CoG values, thus indicating a more retracted point of articulation than Basque /s
However, other participants show similar peaks between Basque /s
̻/ and Spanish /s/. The
production of Basque /s
̺/ also shows two peaks, one that is closer to the higher CoG values
(indicating a complete merger) and another one that is similar to that of Spanish /s/, indicating
that some speakers might not merge the two sibilants in Basque.
Figure 8 shows the productions of the three sibilants per speaker. As can be observed,
there is inter-speaker variation, and most of the participants show variation in the production of
sibilants. Speakers 19, 21, and 25 show lower distribution peaks for Spanish /s/ as opposed to the
distribution peaks of Basque sibilants.
Figure 8. CoG of sibilants in each participant of the Azpeitia group
Below is the output of the statistical model for the Azpeitia group (Table 8):
Table 8. Output of statistical model for Azpeitia group
Lower CrI
Upper CrI
Intercept: Basque /
Basque /s
Spanish /s/
Speaker: random effect
Speaker x Basque /s
Speaker x Spanish /s/
Word: random effect
Cor.: Speaker - Spanish /s/
Cor.: Speaker - Basque /s
Cor.: Speaker - Spanish /s/ - Basque /
As can be observed, the output informs us that, probabilistically speaking, Basque /s
̻/ and
̺/ are merged, since the CrI crosses the zero mark (Est. = 260.44, SE = 271.11, l-95% = -203.22,
u-95% = 677.61). However, the production of Spanish /s/ shows to be different from the rest as
the zero mark is not crossed in the credible intervals (Est. = -654.89, SE = 415.94, l-95% CrI = -
1374.55, u-95% CrI = -50.33).
5.2.2. Lemoa (/s
̺/-merging variety):
As can be observed in Figure 9, there is strong overlap between the three phonemes
produced by the Lemoa group. Examining the means of the sibilants produced by this group,
which are around 6000 Hz, it can be inferred that the merger is in favor of the apico-alveolar
sibilant fricative, as previous literature described.
Figure 9. CoG of sibilants in the Lemoa group
Figure 10 shows the productions per speaker. As can be observed, there is less inter-
speaker variation within this group than in the previous one, indicating that the merger is more
stabilized in this variety. Most speakers merge the three sibilants into one phonetic realization.
Speaker 43 shows a lower peak for Spanish /s/ as opposed to the distribution peaks of the two
Basque sibilants.
Figure 10. CoG of sibilants in each participant of the Lemoa group
Below is the output of the statistical model for the Lemoa group (Table 9):
Table 9. Output of statistical model for Lemoa group
Lower CrI
Upper CrI
Intercept: Basque /s
Basque /s
Spanish /s/
Speaker: random effect
Speaker x Spanish /s/
Speaker x Basque /s
Word: random effect
Cor.: Speaker - Spanish /s/
Cor.: Speaker - Basque /s
Cor.: Speaker - Spanish /s/ - Basque /s
As can be seen in Table 9, the CrI differences between /s
̺/ and /s
̻/ (Est. = 87.36, SE =
105.60, l-95% CrI = -76.41, u-95% CrI = 257.15), and /s
̺/ and /s/ (Est. = -232.11, SE = 194.13, l-
95% CrI = -532.70, u-95% CrI = 72.42), cross the zero mark, showing that there is not 95%
credibility that there is a difference between each of these phoneme pairs, and thus indicating a
likely merger.
5.2.3. Goizueta (non-merging variety):
As seen in Figure 11, Basque /s
̺/ and Spanish /s/ show great overlap, whereas Basque /s
shows clearly distinct values from the other two phonemes.
Figure 11. CoG of sibilants in the Goizueta group
Figure 12 shows there is not considerable inter-speaker variation in the Goizueta group.
Two speakers (26, 27) show slightly higher CoG values for Spanish /s/ than for Basque /s
indicating they have possible different realizations for each sound and therefore map Spanish /s/
as a different sound category. Nonetheless, the general tendency is towards merging of the apico-
alveolar phonemes of Spanish and Basque into one realization.
Figure 12. CoG of sibilants in each participant of the Goizueta group
Below is the output of the statistical model for the Goizueta group (Table 10):
Table 10. Output of statistical model for Goizueta group
Lower CrI
Upper CrI
Intercept: Basque /s
Basque /s
Spanish /s/
Speaker: random effect
Speaker x Basque /s
Speaker x Spanish /s/
Word: random effect
Cor.: Speaker - Spanish /s/
Cor.: Speaker - Basque /s
Cor.: Speaker - Spanish /s/ - Basque /s
Table 10 shows that whereas Basque /s
̺/ and Basque /s
̻/ are realized completely
differently as the CrI range does not cross the zero mark (Est. = 2636.80, SE = 289.09, l-95% CrI
= 2129.15, u-95% CrI = 3061.82), Basque /s
̺/ and Spanish /s/ are merged (Est. = 90.13, SE =
155.45, l-95% CrI = -155.19, u-95% CrI = 335.64).
5.3. RQ3: Similarity of monolingual Spanish speakers’ /s/ to Basque-Spanish bilingual
speakers’ /s/ in Spanish
Monolingual Spanish speakers showed higher CoG values for /s/ than what previous literature
has described, indicating a more fronted PoA (Table 11). Their results are similar to those
obtained in the Azpeitia group (the variety that merges the two alveolar phonemes of Basque into
the lamino-alveolar sibilant). The Lemoa and Goizueta groups show lower CoG values,
indicating a more retracted PoA, most presumably conditioned by the apico-alveolar /s
̺/ in
Basque. As noted by one of the reviewers, it should be considered that on average, /s
̺/ in Basque
has a more posterior PoA than Spanish /s/. Figure 13 shows the production of those sounds by
Table 11. Mean CoG (and its standard deviation) values of /s/ in Spanish by group (in Hz)
6743 (944)
6745 (952)
5636 (713)
5193 (390)
Figure 13. CoG of /s/ in Spanish by each group
Notice how while the distributions of the density curves of the CoG are broader in the
groups that only have one single sibilant fricative (Castilian, Azpeitia, and Lemoa), the
dispersion is much narrower in the Goizueta group, i.e., the only group that has more than one
sibilant fricative in the L1 phonological system. These results align with those obtained as an
answer to RQ1, where the SD of /s/ was significantly lower for the Goizueta group.
To go into greater depth on additional variables, let us recall that the absence vs. the
presence of stress in the syllable where the anterior sibilant was present were not included in the
final model. Indeed, stress effects on CoG were minimal(
). The fact that not all vowel conditions
had the same total number of stressed and unstressed syllables in Spanish, i.e., both /a/ and /i/
had four target tokens per stress condition, but /u/ only had two per condition, could have
allowed the data to show greater/lesser variation.
Regarding the vocalic context in which the Spanish anterior sibilant fricative /s/
appeared, it was found that the preceding vowel /u/ lowered CoG values. Each group showed a
similar trend where /a/ had the highest CoG values, followed by /i/, and then /u/. Table 12
provides a summary of the results and Figure 14 shows a visual representation of those results(
Table 12. Mean CoG (and its standard deviation) of /s/ in Spanish by following vowel (in Hz)
7075 (911)
7093 (915)
5777 (734)
5213 (414)
6727 (933)
6623 (921)
5660 (710)
5274 (312)
6109 (679)
6296 (849)
5311 (575)
4992 (420)
Figure 14. CoG values by group and V2
As previously mentioned, the structure of the optimal model built via the LOO validation
method did not include either SYLLABLE STRESS or V2 as factors; it only included VARIETY as a
fixed factor as well as SPEAKER and WORD as random factors. Below, Table 13 includes the
output of the model for CoG values in Spanish across groups:
Table 13. Output of Bayesian model of CoG of /s/ in Spanish across groups
Lower CrI
Upper CrI
Intercept: Castilian
Azpeitia (/s
Lemoa (/s
Goizueta (non-merging)
Speaker: random effect
Word: random effect
As Table 13 shows, probabilistically speaking, the /s/ produced by the Castilian group
(the intercept) is only akin to that produced by the Azpeitia group (Est. = 10.44, SE = 308.61, l-
95% CrI = -513.39, u-95% CrI = 509.88). The CrI ranges do not cross the zero mark in the
Lemoa (Est. = -1104.54, SE = 320.16, l-95% CrI = -1622.83, u-95% = -589.87) or Goizueta (Est.
= -1535.05, SE = 316.48, l-95% CrI = -2048.25, u-95% = -1021.31) groups; therefore, it is
assumed that their production of /s/ in Spanish is not comparable to that of the intercept’s.
6. Discussion
This study provides data that support the main theoretical claims that were considered in the
introduction. Based on the current results, it has been shown that the group with more than one
anterior sibilant fricative in the L1 shows the lowest degree of acoustic dispersion, as opposed to
the two sibilant-merging varieties in Basque and the monolingual Spanish group. The predicted
hypothesis was therefore met (RQ1, P1). As explained in Flemming’s (2017) Dispersion Theory,
the more phonemic targets that share similar phonological features, the less acoustic dispersion
those phonemes will show. The SD of /s/ in Spanish in the Goizueta group (non-merging Basque
variety) was 2098 Hz, which was significantly different and lower from the other three groups,
Castilian = 2565 Hz, Azpeitia (/s
̻/-merging) = 2841 Hz, Lemoa (/s
̺/-merging) = 2585 Hz. The
difference between the groups that only have one anterior sibilant fricative in their L1 was not
significant, confirming the second prediction (RQ1, P2). Previous literature has explained that
CoG and SD are also correlated, in the sense that the higher the CoG, the higher the SD. If such
claims are considered, then the fact that the Azpeitia group shows the highest SD values could be
attributed to the fact that their CoG values are generally rather high. However, if that applies in
general, the Spanish monolingual group should show higher values, too, which is not seen
here. Regardless, the statistical model showed no significant differences between the three
groups that only have one anterior sibilant fricative in the L1 phonological inventory.
Linguistic transfer was apparent in this study and the predictions made by Flege’s (1995)
Speech Learning Model and Major’s (2001) Ontogeny and Philogeny model are met. The Lemoa
group, which shows the neutralization of the apico-alveolar and lamino-alveolar anterior sibilant
fricatives in favor of the apico-alveolar in Basque, showed a complete merger for the three sound
categories /s
̺/, /s
̻/, and /s/. The speakers of the non-merging variety from Goizueta showed clearly
different values for the two anterior sibilant fricatives in Basque. Yet, these speakers produced
their Basque apico-alveolar fricative and Spanish /s/ identically. As hypothesized (RQ2, P1), the
small L1-L2 differences in articulation between the apico-alveolar sounds in Basque and
Northern Peninsular Spanish would make it difficult for these speakers to map a new sound
category for Spanish /s/. The Azpeitia group, i.e., the variety that merges the apico-alveolar and
lamino-alveolar sibilant fricatives in favor of the lamino-alveolar, showed the expected
neutralization in Basque. Nevertheless, the statistical model demonstrated that these speakers do
not transfer the only anterior sibilant fricative they have in their L1 phonological inventory into
Spanish (RQ2, P2). It can be inferred that the articulatory and acoustic differences between the
lamino-alveolar sibilant fricative and the canonical /s/ in Spanish are sufficient for these speakers
to be able to map a new sound category for Spanish /s/. As opposed to what previous literature
had stated, not all Basque speakers in strongly Basque-speaking towns transfer Basque sibilants
into Spanish. The main difference between these participants and Iribar & Túrrez’s (2015) is that
their participants had little exposure to Spanish. Participants in this study, although they are
inhabitants of towns where the use of Basque is predominant, have received formal instruction in
Spanish at school since the age of six. Therefore, although there is no way to directly compare
the degree of bilingualism between the participants in Iribar & Túrrez (2015) and participants in
this study, it is speculated that it is higher in the present study.
As far as the spectral properties of Basque sibilants are concerned, it is worth mentioning
that the phonetic realizations of the only anterior sibilant fricative in the merging varieties differs
from those in the non-merging varieties. The non-merging variety, Goizueta Basque, shows a
mean COG of 5117 Hz (stdev 308 Hz) for the apico-alveolar /s
̺/, and 7914 Hz (stdev 918 Hz) for
the lamino-alveolar /s
̻/. Azpeitia Basque, the /s
̻/-merging variety, shows a mean COG of 7160 Hz
(stdev 987 Hz) for the apico-alveolar sibilant /s
̺/, and 7450 Hz (stdev 1152 Hz) for the lamino-
alveolar /s
̻/. Finally, Lemoa Basque, the /s
̺/-merging variety, shows a mean COG of 5925 Hz
(stdev 704 Hz) for the apico-alveolar /s
̺/, and 6005 Hz (stdev 725 Hz) for the lamino-alveolar /s
These results would indicate that the phonetic realizations of the merging varieties are not shared
by the non-merging variety. The lamino-alveolar sibilant fricative in the non-merging variety is
more fronted than that produced by the /s
̻/-merging group. Furthermore, the apico-alveolar
sibilant fricative produced by the non-merging variety is more retracted, and as described by
Navarro Tomás (1923), more palatalized than that produced by the /s
̺/-merging group.
Regarding the PoA of /s/ in Spanish by each group, surprisingly, it was found that
monolingual Spanish speakers produced /s/ in a more fronted manner than what previous
literature had described (RQ3, P1). The results of CoG showed that monolingual Spanish
speakers’ mean CoG value was 6743 Hz (stdev 944 Hz), as opposed to 6745 Hz (stdev 952 Hz)
in Spanish produced by the Azpeitia group, 5636 Hz (stdev 713 Hz) by the Lemoa group, and
5193 Hz (stdev 390 Hz) by the Goizueta group. This is remarkable because it would indicate that
the realization of /s/ in Northern Peninsular Spanish is more fronted, and not so apico-alveolar as
dialectological texts describe. The statistical model showed that the realization was shared (or is
comparable) with that of the Azpeitia group, the only group that does not show an apico-alveolar
sibilant fricative in the L1 phonological inventory. As previously explained, the Azpeitia group
showed no transfer from Basque into Spanish /s/, and it was deduced these speakers create a new
sound mapping for Spanish /s/. If CoG results are observed in Table 7, it could be deduced that
the Spanish realization is still somewhat more fronted than ordinary apico-alveolar sounds, 6745
Hz vs. 5636 Hz in the /s
̺/-merging group. Due to the small sample size in the monolingual
Spanish group, no major conclusions can be drawn, nor can one venture to say that a sound
change in progress is happening in Northern Peninsular Spanish.
Regarding the effect of linguistic factors in CoG measurements, the vocalic context
which follows the anterior sibilant fricative has an effect on the mean frequencies. As shown in
Fujisaki & Kunisaki (1978), the /u/ context lowers the frequencies. Nonetheless, unpredictably,
the stress of the syllable where the sibilant appears showed no remarkable differences, as
opposed to the findings of previous literature, i.e., sibilants in stressed syllables show
significantly higher CoG values. It is believed that the lack of a balanced number of target tokens
per vocalic and stress conditions could have interfered in the analysis.
Finally, limitations of this study cannot be disregarded. The sample size was small;
nevertheless, Bayesian probability was used to produce representative results. Although the
present study has helped demonstrate how the L1 sibilant system might have an effect on the L2
sibilant system, and how the number of phonemes that share similar phonological features might
affect the acoustic dispersion of L2 phonemes, there is still much to be studied. Furthermore, a
lack of gender-balanced participants was a limitation. For further studies, a balanced number of
male and female participants should be considered. Besides, the vocalic contexts under
consideration were not balanced, as more target tokens were followed by /a/ and /i/ than by /u/.
Therefore, the results concerning the effect of V2 should be taken with caution. Although
acoustic measurements were useful to describe differences between anterior sibilants in Basque
and the results agree with previous literature, CoG measurements might lack sensitivity and
mean values could be affected by secondary energy sources. Articulatory instruments should be
used to avoid lack of sensitivity and directly examine the PoA of sibilants. Finally, this study
employed weakly informative priors in the analysis, as opposed to strongly informative ones. A
model that can synthesize results from a large body of literature would be able to use strongly
informative priors and provide a clearer picture. The decision was made to use weakly
informative priors since there is not a large body of research which includes several spectral
moments for both Basque and Spanish sibilants. Nevertheless, it is expected that this corpus and
the results obtained from it could serve as part of strongly informative priors in future research.
7. Conclusion
This study has shown that the number of sibilant fricative phonemes in the L1 phonological
system affects the acoustic dispersion of /s/ in L2. The non-sibilant-merging Basque variety of
Goizueta, which has a phonemic contrast between the apico-alveolar /s
̺/ and lamino-alveolar /s
showed a significantly more reduced acoustic dispersion than the sibilant-merging varieties of
Azpeitia Basque and Lemoa Basque, and the Castilian group, which only have one sibilant
fricative in their L1 phonological inventory.
Speakers of Basque varieties with the apico-alveolar /s
̺/ in the L1 phonological system,
i.e., Lemoa Basque and Goizueta Basque, transferred that sound into Spanish /s/. However,
speakers of Azpeitia Basque, which only has a lamino-alveolar sibilant fricative /s
̻/, did not
transfer it. It is thought that acoustic and articulatory dissimilarities with the canonical Peninsular
Spanish /s/ allowed for speakers to have different sound mappings as opposed to the varieties
where the apico-alveolar sound of Basque is remarkably similar to that of Peninsular Spanish.
For these speakers, creating a new sound category for Spanish /s/ is more complicated.
Monolingual Northern Peninsular Spanish speakers showed a more fronted production
than what has been described in literature. Unpredictably, CoG measurements would indicate the
realization of /s/ in Spanish was more lamino-alveolar than apico-alveolar. In fact, the production
by Northern Peninsular Spanish speakers resembled that by Azpeitia speakers, who do not have
an apico-alveolar fricative phoneme in their L1 phonological system.
This has served as a study in the cross-dialectal production of anterior sibilant fricatives
in Basque and Spanish using Bayesian probability for the statistical analysis. It is expected that
future research on acoustic properties of sibilant fricatives in Basque and Northern Peninsular
Spanish could benefit from these results, employing them as possible priors.
[to be added]
Appendix A
Spanish stimuli
Table A1. Target items in Spanish
vowel (V2)
Stressed syllable
Unstressed syllable
/s/ <s>:
pesar /pesáɾ/ ‘to weigh’
pasar /pasáɾ/ ‘to pass’
casar /kasáɾ/ ‘to marry’
besar /besáɾ/ ‘to kiss’
esa /ésa/ ‘that’
César /θésaɾ/ ‘Caesar’
masa /mása/ ‘dough’
casa /kása/ ‘house’
asilo /asílo/ ‘nursing home’
fusil /fusíl/ ‘rifle’
así /así/ ‘like this’
abusivo /abusíbo/ ‘abusive’
básico /básiko/ ‘basic’
música /músika/ ‘music’
músico /músiko/ ‘musician,
casi /kási/ ‘almost’
basura /basúɾa/ ‘trash’
asunto /asúnto/ ‘issue’
asumir /asumíɾ/ ‘to assume’
asustar /asustáɾ/ ‘to scare’
Appendix B
Basque stimuli
Basque items are grouped in two columns according to whether they have orthographic <s> or
<z>. This corresponds to a phonemic distinction only in Goizueta Basque, which I indicate in the
phonological transcription with the corresponding IPA symbols. For the other two varieties
examined here, Azpeitia and Lemoa, both graphemes signal a single phoneme. Thus, the
phonological transcriptions for these two dialects employ a single symbol /s/.
Basque dialects differ considerably in their accentual patterns. The accentual marks that are
provided are based on the author’s perception after listening to the recordings. When variation in
accentuation was found in the experimental data, both attested patterns are given.
Table A2. Target items in Azpeitia Basque (/s
̻/-merging variety)
Vowel (V2)
̺/ <s>
̻/ <z>
esan /esán/ ~ /ésan/ ‘to say’
sasi /sási/ ~ /sasí/ ‘bramble’
besarkada /besarkáda/ ‘hug’
besape /besápe/ ‘armpit’
esanahi /esánai/ ~ /esanái/ ‘meaning’
lasai /lásai/ ~ /lasái/ ‘tranquil’
arnasa /arnása/ ~ /arnasá/ ‘breath’
denborapasa /denboɾápasa/ ‘pastime’
jolasa /xolása/ ~ /xolasá/ ‘game’
geza /ɡesá/ ‘insipid’
meza /mesá/ ‘mass’ (religion)
gogoeza /ɡoɡoésa/ ‘reluctance’
azaldu /asáldu/ ~ /asaldú/ ‘to explain’
ezaugarri /es
̻auɡári/ ‘feature’
terraza /terás
̻a/ ‘terrace’
plaza /plas
̻á/ ‘town square’
azala /as
̻alá/ ‘skin’
hasi /ási/ ~ /así/ ‘to begin’
nagusi /naɡúsi/ ~ /naɡusí/ ‘main’
enfasi /énfasi/ ‘emphasis’
ikasi /ikási/ ~ / ikasí/ ‘to learn’
ikusi /ikúsi/ ~ /ikusí/ ‘to see’
musika /músika/ ‘music’
zerikusi /seɾikúsi/ ‘connection’
hazi /ási/ ~ /así/ ‘to grow’
nazio /nasío/ ‘nation’
biluzik /biʎúsik/ ~ /biʎusík/ ‘naked’
gazi /ɡási/ ~ /ɡasí/ ‘salty’
Andaluzia /andalúsia/ ‘Andalusia’
auzitegi /ausitéɡi/ ‘court house’
jauzi /xáusi/ ~ /xausí/ ‘jump’
pazientzia /pasiéntsia/ ‘patience’
basurde /basúrde/ ‘boar’
kasualitate /kasualídade/ ‘casuality’
asuna /asúna/ ‘nettle’
kasu /kásu/ ‘case’
Arantzazu /aɾantsásu/ (female name)
azukre /asúkɾe/ ‘sugar’
kazuela /kasuéla/ ‘casserole’
enbarazu /enbaɾásu/ ‘embarrassment’
Table A3. Target items in Goizueta Basque (non-merging variety)
Vowel (V2)
̺/ <s>
̻/ <z>
esan /(e)s
̺àn/* ‘to say’
sasi /s
̺ì/* ‘bramble’
besarkada /bes
̺árkada/ ‘hug’
besape /bes
̺àpe/ ‘armpit’
esanahi /es
̺ánai/ ‘meaning’
lasai /las
̺ài/* ‘tranquil’
arnasa /arnás
̺a/ ‘breath’
denborapasa /denbópas
̺a/ ‘pastime’
jolasa /jolás
̺a/ ‘game’
geza /ɡes
̻à/* ‘insipid’
meza /s
̻a/ ‘mass’ (religion)
gogoeza /ɡoɡóes
̻a/ ‘reluctance’
azaldu /as
̻áldu/ ‘to explain’
ezaugarri /es
̻áuɡari/ ‘feature’
terraza /teràs
̻a/ ‘terrace’
plaza /plás
̻a/ ‘town square’
azala /as
̻ála/ ‘skin’
hasi /as
̺ì/* ‘to begin’
nagusi /náus
̺i/ ‘main’
enfasi /ènfas
̺i/ ‘emphasis’
ikasi /(i)kás
̺i/ ‘to learn’
ikusi /(i)kús
̺i/ ‘to see’
musika /mùs
̺ika/ ‘music’
zerikusi /s
̺i/ ‘connection’
hazi /as
̻ì/* ‘to grow’
nazio /nás
̻io/ ‘nation’
biluzik /biʎùs
̻ik/ ‘naked’
gazi /ɡas
̻ì/* ‘salty’
Andaluzia /andálus
̻ia/ ‘Andalusia’
auzitegi /aus
̻íteɡi/ ‘court house’
jauzi /jáus
̻i/ ‘jump’
pazientzia /pas
̻ia/ ‘patience’
basurde /bas
̺úrde/ ‘boar’
kasualitate /kas
̺uálidade/ ‘casuality’
asuna /as
̺úna/ ‘nettle’
kasu /kàs
̺u/ ‘case’
Arantzazu /aɾánts
̻u/ (female name)
azukre /as
̻ùkɾe/ ‘sugar’
kazuela /kas
̻ùla/ ‘casserole’
enbarazu /enbáɾa
u/ ‘embarrassment’
* In isolation, these words would exhibit a word-final rising tone, e.g. hasi /as
̺í/. However, in Goizueta Basque, there
is a tone sandhi rule in which a word-final rising tone shifts to a falling tone when this is followed by a word-initial
rising tone, i.e., σ́#σ́ σ̀#σ́. Target items are followed by the word san /sán/ ‘say’; therefore, /as
̺í s
̺án/ [as
̺ì s
Table A4. Target items in Lemoa Basque (/s
̺/-merging variety)
Vowel (V2)
̺/ <s>
̻/ <z>
esan /esán/ ‘to say’
sasi /sási/ ‘bramble’
besarkada /besárkada/ ‘hug’
besape /besápe/ ‘armpit’
esanahi /esánai/ ‘meaning’
lasai /sai/ ‘tranquil’
arnasa /arnása/ ‘breath’
denborapasa /denbóɾapasa/ ‘pastime’
jolasa /jolása/ ‘game’
geza /ɡésa/ ‘insipid’
meza /mésa/ ‘mass’ (religion)
gogoeza /ɡoɡóesa/ ‘reluctance’
azaldu /asáldu/ ‘to explain’
ezaugarri /esáuɡari/ ‘feature’
terraza /terása/ ‘terrace’
plaza /plása/ ‘town square’
azala /asála/ ‘skin’
hasi /ási/ ~ /así/ ‘to begin’
nagusi /naɡúsi/ ‘main’
enfasi /énfasi/ ‘emphasis’
ikasi /ikási/ ‘to learn’
ikusi /ikúsi/ ~ /ikusí/ ‘to see’
musika /músika/ ‘music’
zerikusi /seɾíkusi/ ‘connection’
hazi /ási/ ~ /así/ ‘to grow’
nazio /nasío/ ‘nation’
biluzik /bilúsik/ ‘naked’
gazi ási/ ‘salty’
Andaluzia /andálusia/ ‘Andalusia’
auzitegi /ausíteɡi/ ‘court house’
jauzi /jáusi/ ~ /jausí/ ‘jump’
pazientzia /pasiéntsia/ ‘patience’
basurde /basúrde/ ‘boar’
kasualitate /kasuálitate/ ‘casuality’
asuna /asúna/ ‘nettle’
kasu /kásu/ ‘case’
Arantzazu /aɾántsasu/ (female name)
azukre /asúkɾe/ ‘sugar’
kazuela /kasuéla/ ‘casserole’
enbarazu /enbáɾasu/ ‘embarrassment’
Beristain, Ander. 2018a. The acoustic realization of /s
̺/ and /ts
̻/ by L1 and L2 Basque speakers. In
Lorea Unamuno, Asier Romero, Aintzane Etxebarria & Aitor Iglesias (eds.), Linguistic
variation in the Basque language and education, vol. 3, 7082. Bilbao: University of the
Basque Country Press.
Beristain, Ander. 2018b. Azpeitiko euskararen hiztegi dialektal bat (I) [A dialectal dictionary of
Azpeitia Basque (Part I)]. Fontes Linguae Vasconum 125, 754.
Beristain, Ander. 2019. Azpeitiko euskararen hiztegi dialektal bat (II) [A dialectal dictionary of
Azpeitia Basque (Part II)]. Fontes Linguae Vasconum 127, 758.
Best, Catherine T. 2001. Discrimination of non-native consonant contrasts varying in perceptual
assimilation to the listener’s native phonological system. The Journal of the Acoustical
Society of America 109(2), 775794.
Bialystok, Ellen. 1994. Analysis and control in the development of second language proficiency.
Studies in Second Language Acquisition 16, 157168.
Boersma, Paul & David Weenink. 2019. Praat: doing phonetics by computer (version 6.048). (accessed 25 April 2019).
Boersma, Paul. 2002. Praat: an online manual.
(accessed 20 March 2018)
Bonaparte, Louis L. 1869. Carte des sept provinces basques, montrant la délimitation actuelle de
l’euscara. London: Standford’s Geographical Society.
Bosch, Laura & Núria Sebastián-Gallés. 2001. Evidence of early language discrimination
abilities in infants from bilingual environments. Infancy 2, 2949.
Bürkner, Paul-Christian. 2017. brms: An R Package for Bayesian Multilevel Models Using Stan.
Journal of Statistical Software 80(1), 128.
Chodroff, Eleanor. 2017. Structured variation in obstruent production and perception. Ph.D.
dissertation, John Hopkins University.
Cicres, Jordi. 2011. Los sonidos fricativos sordos y sus implicaciones forenses. Estudios
Filológicos 48, 3348.
Dryer, Matthew S. & Martin Haspelmath. (eds.). 2013. The World Atlas of Language Structures
(WALS) online. Leipzig: Max Planck Institute for Evolutionary
Anthropology. (accessed May 1 2019).
Elejabeitia, Ana & Gema Bizcarrondo. 1992. La S en el español de Vizcaya. Bilbao: Universidad
de Deusto.
Etxebarria, Maitena. 1997. Bilingüismo y adquisición temprana del lenguaje: Procesos
fonológicos en el contacto vasco/español. In First International Symposium on
Bilingualism: Bilingual Communities and Individuals, 237-265. Vigo: Universidad de
Flege, James E. 1995. Second language speech learning. Theory, findings, and problems. In
Winifred Strange (ed.), Speech perception and linguistic experience: Issues in cross-
language research, 233277. Timonium, MD: York Press.
Flege, James E. 2002. Interactions between the native and second-language phonetic systems. In
Petra Burmeister, Thorsten Piske & Andreas Rohde (eds.), An integrated view of
language development: Papers in honor of Henning Wode, 217243. Trier:
Wissenschaftlicher Verlag Trier.
Flege, James E. 2007. Language contact in bilingualism: Phonetic system interactions. In
Jennifer Cole & José I. Hualde (eds.), Laboratory Phonology 9, 353381. New York:
Mouton de Gruyter.
Flege, James E., Carlo Schirru & Ian R.A. MacKay. 2003. Interactions between the native and
second language phonetic subsystems. Speech Communication 40(4), 467491.
Flemming, Edward. 2017. Dispersion Theory and phonology. In Mark Aronoff (ed.), The Oxford
research encyclopedia. Oxford. Oxford University Press.
Fujisaki, Hiroya & Osamu Kunisaki. 1978. Analysis, recognition, and perception of voiceless
fricative consonants in Japanese. IEEE Transactions 26, 2127.
Gaminde, Iñaki, Lorea Unamuno, Aitor Iglesias & Leire Gandarias. 2013. Bizkaiko neska
gazteen kontsonante afrikatuan izari akustikoez [On the acoustic cues of affricate
consonants by young Biscayan girls]. Euskalingua 23, 613.
Gaminde, Iñaki. 2002. Bizkaiko euskararen ezaugarri fonologiko batzuen inguruan [On some
phonological characteristics of Biscayan Basque]. Euskalingua 1, 414.
Henriksen, Nicholas & Sarah K. Harper. 2016. Investigating lenition patterns in south-central
Peninsular Spanish /sp st tk/ clusters. Journal of the International Phonetic Association
46(3), 287310.
Hualde, José I. & Ander Beristain. 2017. Azpeitiko azentuaren gauzatze fonetikoaz [On the
acoustic realization of stress in Azpeitia Basque]. Fontes Linguae Vasconum 123, 6586.
Hualde, José I. & Ander Beristain. 2018. Acoustic correlates of word-accent in Basque.
Proceedings of TAL2018, Sixth International Symposium on Tonal Aspects of Languages,
Hualde, José I. & Ander Beristain. 2019. Bi alofonia-gertakari Azpeitiko euskaran [Two
allophony phenomena in Azpeitia Basque]. In Aintzane Etxebarria, Aitor Iglesias, Hiart
Lejarreta & Asier Romero (eds.), Traineru bete lagun: Iñaki Gaminde omenduz, 209
228. Bilbao: University of the Basque Country Press.
Hualde, José I. & Ander Beristain. 2020. New Basque varieties: Accentuation and grammatical
number in Standard Basque and local dialects. In Lenore Grenoble, Pia Lane & Unn
Røyneland (eds.), Linguistic Minorities in Europe Online, n.d., Berlin, Boston: De
Gruyter Mouton. (accessed 31 July
Hualde, José I. & Oihana Lujanbio. 2008. Goizuetako azentua [Stress in Goizueta Basque]. In
Xabier Artiagoitia & Joseba A. Lakarra (eds.), Gramatika jaietan: Patxi Goenagaren
omenez, 377-394. Bilbao: University of the Basque Country Press.
Hualde, José I. 1997. Euskararen azentuerak [Basque accentuations]. Donostia: Gipuzkoako
Foru Aldundia and the University of the Basque Country.
Hualde, José I. 2010. Neutralización de sibilantes vascas y seseo en castellano. Oihenart 25, 89
Hualde, José I., Oihana Lujanbio & Francisco Torreira. 2008. Lexical tone and stress in Goizueta
Basque. Journal of the International Phonetic Association 38(1), 124.
Hualde, José I., Oihana Lujanbio & Juan J. Zubiri. 2010. Goizueta Basque. Journal of the
International Phonetic Association 40(1), 113127.
Iribar, Alexander & Carmen Isasi. 2008. El seseo vasco: Nuevos datos para una vieja cuestión.
Oihenart 23, 241258.
Iribar, Alexander & Itziar Túrrez. 2015. El seseo vasco: Caracterización fonética. Estudios de
Fonética Experimental 24, 205235.
Iribar, Alexander, Carmen Isasi, Sara Gómez Seibane & Carmen Moral del Hoyo. 2005. Notas
para la descripción acústica del seseo vizcaíno. In Manuel González, Elisa Fernández &
Begoña González (eds.), III Congreso Internacional de Fonética Experimental, 389398.
Santiago de Compostela: Xunta de Galicia.
Isasi, Carmen, Alexander Iribar & Carmen Moral del Hoyo. 2009. Una transferencia vasca: El
seseo de hablantes vizcaínos y guipuzcoanos. Oihenart 24, 201235.
Jesus, Luis M.T. & Christine H. Shadle. 2002. A parametric study of the spectral characteristics
of European Portuguese fricatives. Journal of Phonetics 30(3), 437464.
Johnson, Keith. 2011. Acoustic and auditory phonetics. Hoboken, NJ: Wiley-Blackwell.
Jongman, Allard, Ratree Wayland & Serena Wong. 2000. Acoustic characteristics of English
fricatives. The Journal of the Acoustical Society of America 108(3), 12521263.
Jurado, Mirari. 2011. Caracterización de sibilantes fricativas vascas y su percepción en el sistema
fonético español. ASJU-International Journal of Basque Linguistics and Philology 45,
Larraza, Saioa, Arthur G. Samuel & Miren L. Oñederra. 2016a. Where do dialectal effects on
speech processing come from? Evidence from a cross-dialect investigation. The
Quarterly Journal of Experimental Psychology 70, 92108.
Larraza, Saioa, Arthur G. Samuel & Miren L. Oñederra. 2016b. Listening to accented speech in a
second language: First language and age of acquisition effects. Journal of Experimental
Psychology: Learning, Memory, and Cognition 11, 17741797.
Li, Fangfang, Jan Edwards & Mary E. Beckman. 2009. Contrast and covert contrast: The
phonetic development of voiceless sibilant fricatives in English and Japanese toddlers.
Journal of Phonetics 37, 111–124.
Lujanbio, Oihana. 2016. Hizkuntza aldakortasuna euskaran: Nafarroako ekialdeko bi udalerritan
egindako azterketa [Language variation in Basque: An investigation conducted in two
towns in Eastern Navarre]. Ph.D. dissertation. University of the Basque Country.
Lujanbio, Oihana. 2018. Goizuetako azentu-hiztegia [An accent dictionary of Goizueta Basque].
ASJU-International Journal of Basque Linguistics and Philology 47(2), 186.
Maddieson, Ian. 1984. Patterns of sounds. Cambridge, UK: Cambridge University Press.
Maddieson, Ian. 1997. Phonetic universals. In William J. Hardcastle, John Laver & Fiona E.
Gibbon (eds.), The handbook of phonetic sciences, 619–639. Oxford: Blackwell.
Maddieson, Ian. 2014. LAPSyD: Lyon–Albuquerque Phonological Systems Database. Lyon:
CNRS. (accessed 9 March 2020).
Major, Roy C. 2001. Foreign accent: The ontogeny and phylogeny of second language
phonology. Mahwah, NJ and London: Lawrence Erlbaum Associates.
Mielke, Jeff. 2018. Visualizing phonetic segment frequencies with density-equalizing
maps. Journal of the International Phonetic Association 48(2), 129154.
Munibe, Xabier. 1764. El borracho burlado. Vitoria: Robles y Navarro.
Muxika-Loitzate, Oihane. 2017. Sibilant merger in the variety of Basque spoken in Amorebieta-
Etxano. Languages 2(4), 25.
Navarro Tomás, Tomás. 1923. Observaciones Fonéticas sobre el vascuence de Guernica.
Congreso de Estudios Vascos III, 4956.
Newman, Rochelle S. (2003). Using links between speech perception and speech production to
evaluate different acoustic metrics: A preliminary report. The Journal of the Acoustical
Society of America 113(5), 2850–2860.
Newman, Rochelle S., Sheryl A. Clouse & Jessica L. Burnham. 2001. The perceptual
consequences of within-talker variability in fricative production. The Journal of the
Acoustical Society of America 109(3), 1181–1196.
Nissen, Shawn L. & Robert A. Fox. 2005. Acoustic and spectral characteristics of young
children’s fricative productions: A developmental perspective. The Journal of the
Acoustical Society of America 118(4), 2570-2578.
Paasch-Kaiser, Christine. 2013. El castellano de Getxo: Estudio empírico de aspectos
morfológicos, sintácticos y semánticos de una variedad del castellano hablado en el País
Vasco. Berlin/Boston: De Gruyter.
R Core Team. (2019). R: A language and environment for statistical computing. Vienna, Austria:
R Foundation for Statistical Computing. URL<>.
Reidy, Patrick F. 2016. Spectral dynamics of sibilant fricatives are contrastive and language
specific. The Journal of Acoustical Society of America 140(4), 25182529.
Sebastián-Gallés, Núria & Laura Bosch. 2002. Building phonotactic knowledge in bilinguals:
Role of early exposure. Journal of Experimental Psychology 28(4), 974989.
Segura, Maitane. 2014. Percepción y producción de las sibilantes vascas por aprendices adultos
de euskera con español como L1. M.A. thesis. Consejo Superior de Investigaciones
Vasishth, Shravan, Bruno Nicenboim, Mary E. Beckman, Fangfang Li & Eun J. Kong. 2018.
Bayesian data analysis in the phonetic sciences: A tutorial introduction. Journal of
Phonetics 71, 147161.
Vehtari, Aki, Andrew Gelman & Jonah Gabry. 2017. Practical Bayesian model evaluation using
leave-one-out cross-validation and WAIC. Statistics and Computing 27, 1413–1432.
Wickham, Hadley. 2016. ggplot2: Elegant graphics for data analysis. New York: Springer-
Yárnoz, Belén. 2001. Sibilants in the Basque dialect of Bortziri: An acoustic and perceptual
study. Pamplona: Gobierno de Navarra.
Yrizar, Pedro. 1991. Morfología del verbo auxiliar guipuzcoano: Tomo I, Subdialecto
Septentrional. Zarautz: Euskaltzaindia.
Yrizar, Pedro. 1992. Morfología del verbo auxiliar vizcaíno: Estudio dialectológico. Bilbao:
Yrizar, Pedro. 2008. Morfología del verbo auxiliar vasco. Bilbao: Euskaltzaindia.
Zuazo, Koldo. 2014. Euskalkiak [The Basque dialects]. Donostia: Elkar.
Zuazo, Koldo. 2019. Standard Basque and its dialects. New York, NY: Routledge.
Zubiri, Juan J. & Patziku Perurena. 1998. Goizueta eta Aranoko hizkerak [The varieties of
Goizueta and Arano]. Pamplona-Iruñea: Nafarroako Gobernua & Goizuetako eta
Aranoko Udalak.
Zubiri, Juan J. 2000. Arano eta Goizuetako hizkera [The varieties of Arano and Goizueta]. In
Koldo Zuazo (ed.), Dialektologia gaiak, 85–120. Vitoria-Gasteiz: Diputación Foral de
Alava/Arabako Foru Aldundia.
) See Jurado’s (2011: 101–104) description of several acoustic measurements in relation to
sibilants and their correlation with PoA.
) No effect of LANGUAGE ORDER was found.
) Below 5%, which is the standard alpha level in research in the social sciences.
) Notice here and henceforth that SD corresponds to the second spectral moment, i.e., variance,
whereas ‘standard deviation (stdev)’ references the statistical descriptive measure.
) Differences in the stressed (vs. unstressed) condition were on the order of 69 Hz higher in the
Castilian group (stressed: 6777 vs. unstressed: 6708 Hz), 157 Hz higher in the Azpeitia group
(stressed: 6824 vs. unstressed: 6667 Hz), 41 Hz lower in the Lemoa group (stressed: 5616 vs.
unstressed: 5657 Hz), and 83 Hz higher in the Goizueta group (stressed: 5234 vs. unstressed:
5151 Hz).
) The author acknowledges that it is somewhat puzzling that CoG values are not the highest
before /i/ considering CoG fundamentally relates to the length of the vocal tract downstream
of the constriction. After consulting other studies such as Segura (2014: 44–46), it was found
that such strict correlation is not found either. Nevertheless, this matter deserves further
analysis and could be an interesting line for future research.
... In Basque historical phonology, the study of consonants has prevailed over that of vowels (Michelena 1990;Lakarra 1995;Lakarra 2013;Trask 1997;Egurtzegi 2013). Among processes affecting consonants, the changes that have altered the phonological opposition between pairs of fricative and affricate sibilants with different places of articulation have aroused considerable interest, with renewed discussion in recent times (Muxika-Loitzate 2017; Egurtzegi & Carignan 2020;Beristain 2021). The interest of the Basque sibilant system lies in its relative complexity: it includes voiceless fricative-affricate pairs with three contrasting places of articulation -lamino-alveolar (/s̻ / and /t ͡ s̻ /), apico-alveolar (/s̺ / and /t ͡ s̺ /) and postalveolar (/ʃ/ and /t ͡ ʃ/) -and voiced counterparts of these in some eastern varieties (cf . ...
... In addition to the Western merger, we also analyse the "Central merger" (Figure 2), an innovation which developed during the 17th-19th centuries in some central varieties. In this merger, fricative and affricate alveolar sibilants are realised as fricative and affricate laminals (see Beristain 2018;Beristain 2019;Beristain 2021 for analyses of modern data). This paper presents two main novelties. ...
Full-text available
Conservative Basque dialects distinguish apical and laminal alveolar sibilants in the fricative and affricate series. This paper analyses the changes this system was undergoing in the Central Basque variety of San Sebastián in the 18th century: (1) the “Western merger”: neutralisation of the laminal and apical fricative sibilants in favour of the latter and the neutralisation of the laminal and apical alveolar affricates in favour of the former, which started in Western Basque and spread to some Central varieties, and (2) the “Central merger”, a more recent development, limited to some central dialects, where both fricative and affricate alveolar sibilants are realised as laminals. A generalised linear mixed-effects model was fitted to the data extracted from an early-18th-century manuscript which shows evidence of both patterns of merger. We propose that sibilant mergers were still in progress in the variety and time period under study and that they are interrelated processes. The Western merger started as a phonetically-conditioned sound change due to coarticulation to a following consonant. As this neutralisation extended to other positions, a hypercorrective change was initiated in some Central varieties, which eventually resulted in a mirror-image process, namely a change from apical to laminal fricatives.
This Illustration of the IPA describes the sound system of the local dialect of Basque ( euskara , euskera , IS0-639-3 eus) spoken in the town of Markina-Xemein, in the province of Bizkaia (Biscay), within the Basque Autonomous Community of Spain (see maps in Figures 1 and 2. Speakers of this local variety of Basque refer to it as markiñarra or Markiñeko euskerie .
Full-text available
This dissertation investigates language-specific acoustic and aerodynamic phenomena in language contact situations. Whereas most work on second language and bilingual phonology has focused on individual consonants and vowels, this project examines patterns of coarticulation in the two languages of Spanish-English and French-English bilingual speakers. These include speakers whose first language is either Spanish, French or English, and are late second-language acquirers, and heritage speakers of Spanish, who are early second-language acquirers. I focus on subtly different coarticulation patterns between English and Spanish, including the extent to which vowels are nasalized in contact with nasal consonants (Chapter 2), are lengthened before voiced consonants (Chapter 3), and whose quality is affected before voiced consonants (Chapter 4). Whereas the existence of such effects can be taken as universal, the degree to which they are implemented varies from language to language, presumably contributing to what defines a ‘native accent.’ My work thus presents a novel method to investigate coarticulatory patterns. The theoretical question that I address in my dissertation is whether bilingual speakers can establish distinct coarticulatory patterns in their two languages in ways that are similar to those of monolinguals of the two languages. A related question is to what extent learning both languages in childhood (as in the case of heritage speakers) facilitates separating the two phonetic systems. In Chapter 2, I study coarticulatory vowel nasalization in Spanish and English using pressure transducers and Generalized Additive Mixed Models to observe how nasal airflow changes over time. In Chapter 3, I focus on vowel length as a cue for voicing of the following consonant in two Romance languages (Spanish, French) and English, which show opposite patterns. Chapter 4 is about vowel formant displacement patterns across time and the effect of vocalic length in Spanish and English. In Chapter 5, I present a new phonological model, “The Bilingual Coarticulatory Model”, which describes coarticulation as malleable and adjustable cross-linguistically in bilingual speakers that possess a higher level of linguistic proficiency. Results show that properties pertaining to vowel quality are easier to acquire than durational properties, which would go against some of the L2 literature on the acquisition of vowels. Native speakers of Spanish show native-like nasalization values in L2 English, yet only when the syllabic structure of sequences is shared. Heritage speakers show native-like results in both languages with regard to nasalization, and L1En speakers show an adjustment of onset of nasalization but not of degree of nasalization. Regarding duration, heritage speakers were the only group to completely separate the two coarticulatory systems, as the other groups showed cross-linguistic influence. Finally, regarding the dynamics of vowel formants, speakers transfer L1 patterns to the L2. Linguistic proficiency in the L2 was a significant factor to acquire coarticulatory patterns. In the case of heritage speakers, different findings were found depending on the variable under study.
Full-text available
This tutorial analyzes voice onset time (VOT) data from Dongbei (Northeastern) Mandarin Chinese and North American English to demonstrate how Bayesian linear mixed models can be fit using the programming language Stan via the R package brms. Through this case study, we demonstrate some of the advantages of the Bayesian framework: researchers can (i) flexibly define the underlying process that they believe to have generated the data; (ii) obtain direct information regarding the uncertainty about the parameter that relates the data to the theoretical question being studied; and (iii) incorporate prior knowledge into the analysis. Getting started with Bayesian modeling can be challenging, especially when one is trying to model one’s own (often unique) data. It is difficult to see how one can apply general principles described in textbooks to one’s own specific research problem. We address this barrier to using Bayesian methods by providing three detailed examples, with source code to allow easy reproducibility. The examples presented are intended to give the reader a flavor of the process of model-fitting; suggestions for further study are also provided. All data and code are available from:
Lan honetan, Azpeitiko hizkeraren azentuaren ezaugarri akustikoak aztertzen ditugu. Singular/plural hitz pareak erabili ditugu bokal azentudunen eta azentugabeen arteko diferentzia akustikoak miatzeko. Emaitzek erakusten dute tonuak eta intentsitateak azentu-gunea adierazten dutela. Bereziki, aztertu dugun testuinguruan, silaba azentu-dunek tonu gorakada erakusten dute. Iraupena, alderantziz, ez da erabiltzen azentuaren ezaugarri esanguratsu bezala. Emaitza hauek beste euskal hizkera batzuen datuekin konparatzen ditugu eta iraupenaren azentuzko erabilerak bokalen galera gertakarietan izan dezakeen eragina kontsideratzen dugu.
Hiztegi honen ildo nagusiak Azpeitiko euskararen azentua eta fonologia dira. Hiztegian, azpeitieraz gertatzen diren aldaketa fonologikoak azaldu dira. Izenen eta izenondoen kasuetan, hiru forma aurkeztu dira. Lehena, flexiorik gabeko absolutiboko forma mugagabea da, eta ondorengo biak kopuladunak, bai singularrean bai pluralean. Hiru formak azentu aldaketa adierazteko erabili dira. Aditzen kasuan, partizipio perfektiboan eta ez-perfektiboan ageri zaizkigu, beti ‘da/du’ aditz laguntzailearekin. Bestelako hitz motak forma bakarrean datoz. Lan hau hiztegi osoaren lehen erdia da.
LABURPENA Lan hau hiztegiaren bigarren erdia da. Aurreko lanean bezala hiztegiaren ildo nagusiak Azpeitiko euskararen azentua eta fonologia dira. Izenen eta izenondoen kasuetan, hiru forma aurkeztu dira. Lehena, flexiorik gabeko absolutiboko forma mugagabea da, eta ondorengo biak kopuladunak, bai singularrean bai pluralean. Aditzen kasuan bi forma ageri dira, partizipio perfektiboan eta ez-perfektiboan, beti ‘da/du’ aditz laguntzailearekin. Bestelako hitz motak forma bakarrean datoz. RESUMEN Este trabajo es la segunda mitad que compone el diccionario. Como en el escrito anterior, se centra en la acentuación y fonología del euskera de Azpeitia. En el diccionario los sustantivos y adjetivos aparecen en tres formas: la forma nuda, y seguidamente la forma de singular y plural en caso absolutivo. Los verbos aparecen en dos formas, el participio perfectivo e imperfectivo, seguido por el auxiliar de tercera persona. Las demás categorías verbales solo muestran una forma. ABSTRACT This is the second half of the dialectal dictionary. Like in the previous work, the dictionary focuses on the accent and phonology of Azpeitia Basque. In the dictionary, nouns and adjectives are shown in three different forms: uninflected, absolutive singular and absolutive plural. Regarding verbs, two different forms are used throughout the dictionary: the perfective and non-perfective forms, followed by a third person singular auxiliary. As for the remaining word categories, only one form is given.
In this article, we examine some aspects of the interaction between Standard Basque (see also Jauregi & Epelde in LME 2019) and traditional varieties of the Basque language. The questions that arise in this context are, on the one hand, the possible “substrate” effects of local varieties on the pronunciation of Standard Basque, so that Standard Basque may be starting to show regional variation, and, on the other, the influence that Standard Basque may be having on traditional local varieties. We focus on the singular/plural distinction, which in many traditional varieties is conveyed by differences in accentuation and in Standard Basque, instead, is expressed by differences in the segmental shape of suffixes. The results of our preliminary investigation show that accentual distinctions between singular and plurals (or other accentual contrasts) are generally not transferred to Standard Basque. That is, in some geographical areas, speakers use different accentual rules in Standard Basque and when speaking in their native dialect. On the other hand, in some other geographical areas, traditional contrasts in accentuation are no longer being made, showing perhaps convergence with the Standard in this respect; but speakers still use different morphological endings and different morphophonological rules in the two varieties that they speak. By focusing on this specific aspect of linguistic structure (accentuation and morphological number marking) we wish to contribute to a better understanding of the complex interaction between traditional Basque varieties and Standard Basque.
Este estudio está dedicado al castellano hablado en la Comunidad Autónoma Vasca (CAV o País Vasco) y, en particular, en Getxo. La autora investiga si el castellano hablado en esta región es una única variedad, o bien se compone de diversas variedades, con un núcleo común, usadas por los diferentes grupos de hablantes de la comunidad de comunicación vasca. En la parte teórica, el estudio responde a esta pregunta elaborando una definición de qué debe entenderse por «castellano del País Vasco», teniendo en cuenta diversos factores sociales relevantes a la hora de describir la comunidad de comunicación vasca. Le precede un amplio repaso de otros trabajos dedicados al castellano hablado en la CAV. En virtud de la definición propuesta se añade un estudio basado en un corpus oral de 20 entrevistas con informantes castellanohablantes monolingües de Getxo. Realizado desde una perspectiva variacional, dicho estudio analiza, cualitativamente, 17 fenómenos lingüísticos que se suelen considerar característicos del castellano del País Vasco. Asimismo, se proporcionan datos cuantitativos sobre la ocurrencia de cada fenómeno. A partir de sus resultados, la autora razona cuáles de los fenómenos estudiados forman parte del castellano de Getxo. Elise-Richter-Preis des DRV 2015