The present paper aims at providing empirical evidence for dialectal variation concerning the perception of the central vowel [ɐ] in European Portuguese (EP). More concretely, this study compares the perception of the contrast between [a] and [ɐ] by native speakers of two varieties of EP: 23 speakers of a northern Portuguese dialect (from the city of Braga) and 23 speakers of the Littoral Center variety of EP (from the city of Lisbon, defined as Standard European Portuguese (SEP)). Based on a discrimination test, the results show that the two groups of speakers differ with respect to the perception of the contrast between the two central vowels under investigation. The speakers of the northern variety differentiate less between the two central vowels compared to the speakers from Lisbon.
It has been mentioned in a number of studies that the European Portuguese (EP) dialect spoken in the region of Braga in northern Portugal differs from the EP variety spoken in the Lisbon area with respect to the realization of the central vowels. More precisely, it has been reported in the literature that in stressed syllables, the Littoral/Center dialect shows allophonic variation of [a] and [ɐ], whereas the open vowel [a] is predominant in the north (
This observation has been corroborated in acoustic studies focussing on language production which have shown that in the speech of Braga, the vowels [ɐ] and [a] are acoustically and articulatorily equivalents in the tonic syllable (cf.
The present paper takes the findings of Varanda, Barroso & Rato (
According to Mateus, Falé & Freitas (
(1) | [i] | (closed/front), [ɨ] (closed/central), [u] (closed/back), [e] (midclosed/front), |
[ɐ] | (midclosed/central), [o] (midclosed/back), [ɛ] (midopen/front), [ɔ] (midopen/back), | |
[a] | (open/central) |
With respect to lip rounding, [o], [ɔ] and [u] are rounded vowels; [a], [ɛ], [e], [ɐ], [i] and [ɨ] are unrounded. The two vowels under consideration in this study, [a] and [ɐ] are both central; they differ with respect to the opening of the jaw: [a] is more open than [ɐ].
Acoustically, the formants F1 (degree of opening or height of the tongue), F2 (position of the tongue) and F3 (roundedness of the lips) are used for the identification of vowels. In the case of [a] and [ɐ], the difference between [a] and [ɐ] will be reflected in different F1 values.
With regard to phonemic status, Mateus, Falé & Freitas (
According to Frota et al. (
The northern varieties of EP further divide into the Transmontano and Alto-Minhoto dialect and the Baixo-Minhoto, Duriense and Beirão dialect; the central-southern varieties consist of the Littoral Center dialect and the Interior Center and South variety. Figure
Main varieties of EP, based on Cintra (
The present study concentrates on the comparison of the variety of EP spoken in the Braga area and the variety of EP spoken in the Lisbon area with respect to the perception of the contrast [a] and [ɐ]. The Lisbon dialect is part of the Littoral Center varieties and considered to be the Standard Variety of EP (SEP). The dialect of Braga belongs to the northern dialects and is part of the Baixo Minhoto variety.
As already mentioned, the Braga dialect has been described in many studies to differ phonologically from SEP with respect to the realization of [a] and [ɐ]. In the Standard dialect, /a/ is realized as [ɐ] in unstressed position or in stressed open syllables before a nasal consonant (cf.
Realizations of [a]–[ɐ] in different contexts in the two dialects.
[a]–[ɐ] | |||||
---|---|---|---|---|---|
Stressed syllable | Open syllable | Nasal context | Realization in Lisbon | Realization in Braga | |
+ | – | – | [a] | [a] | |
– | – | – | [ɐ] | [ɐ] | |
+ | + | + | [a] | [a] | |
nós tom |
+ | + | + | [ɐ] | [a] |
Rodrigues & Martins (
Rodrigues, Rato & Silva (
Based on these previous findings, Varanda (
The comparison with studies by Escudero et al. (
Varanda, Barroso & Rato (
Based on what we know so far about dialectal differences concerning the production of [ɐ] and [a] in the stressed syllable, the present study focuses on the
Our main research question is therefore the following:
Is there a dialectal difference concerning the perception of [ɐ] and [a] in monosyllabic pseudowords between the speakers of Braga and Lisbon?
Given the results of acoustic studies which have shown that speakers from the Braga region in contrast to speakers from Lisbon differentiate less (or not at all) between [ɐ] and [a] in stressed syllables, we predict that they may also differ with respect to the perception of the contrast [ɐ]–[a]. The tendency towards the absence of [ɐ] in production in the Braga dialect suggests that the sound contrast between [ɐ] and [a] in stressed syllables is less strong in this variety.
This does, however, not mean that speakers living in the city of Braga will generally be unable to distinguish between the two sounds. Given the fact that the Lisbon variety represents the Standard European Portuguese dialect, which is present in the media and in formal settings, we expect that speakers of the Braga variety will not be completely ignorant of the vowel contrast. This means that they may show some perception abilities of the vowel contrast but they will differentiate less between the two vowels and show a higher degree of intra- and inter-individual variation than the speakers from Lisbon.
This study consists of an online vowel discrimination task, which was conducted with the perception tool
A total of 46 speakers living in two different regions of Portugal participated in this experiment. Their consent to participate in the study was obtained before they started. According to the sociobiographical questionnaire, 23 participants were born and have always lived in the Lisbon area and 23 participants are from the northern Portuguese area around Braga and have always lived in this region. The participants’ age ranges from 18 to 50 years (mean: 25; SD: 8.67), 33 identify themselves as female, 12 as male and one as other. 31 out of 46 participants are university students, the remaining 15 already obtained an academic degree. The majority of the test subjects studied or studies humanities (43), only three have a different academic background. All participants were raised in a monolingual context in Portugal and learned one or more second languages later in life, mostly English. It is important to stress that the northern variety is generally present in all social contexts, i.e., there is no diaglossic distribution of dialectal use and no division into high and low variety in the sense of Ferguson (
The vowel identification task was based on Darcy & Krüger’s (
Out of the 28 sequences, 12 were the test items that only contained the vowel contrast between [a] and [ɐ]. Another 12 sequences served as control items and included a contrast between the target vowels and [i] (i.e., [a]–[i] and [ɐ]–[i]). Given that [i] is acoustically and articulatorily very different from both [a] and [ɐ], discrimination should be easy if the participants correctly understood the task. The remaining four sequences were used as distractors as they contained three times the same target vowel, i.e., the participants heard sequences with three identical pseudo-words (catch trials).
The stimuli were produced by three female native speakers of EP from the region of Braga. All of them have phonetic/phonological knowledge and were sensitive to the difference between [a] and [ɐ]. They were recorded in a sound cabin at the University of Minho in Braga, Portugal. The four test item pseudo-words ([baʃ], [bɐʃ], [zaʃ], [zɐʃ]) as well as two control item words ([biʃ], [ziʃ]) were implemented in the carrier sentence “
For each stimulus, the interstimulus interval (ISI) between the three CVC words was determined as 1.5 seconds, following Colantoni, Steele & Escudero’s explanation: “It has been argued that an ISI of 500 ms promotes acoustic rather than phonological comparisons between sound, while an ISI of 1.5 seconds or more ensures phonological processing” (
Screenshot of the perception test design.
A mixed-effect model was applied for statistical analysis, conducted in SPSS version 26. In section 3.3 we will present the descriptive results and the statistical analysis.
We will start by presenting the accuracy scores for all 28 test conditions. Subsequently, we will have a closer look on the target vowels [a] and [ɐ] and present the results for those conditions where they are directly contrasted to each other. We will then compare these results to the accuracy rate in contrast to the control item [i]. Finally, the accuracy scores for the distractor items (catch trials) will be shown.
Table
Overview of the results.
Braga ( |
Lisbon ( |
|
---|---|---|
I. Overall correct identification, all 28 items, including distractors | 516/644 | 593/644 |
% correct overall identification: mean % (SD), including distractors | 80.1% (11.7) | 92.1% (5.9) |
Min./max. value in % | 57.1/100% | 78.6/100% |
IIa. Correct identification, control item contrast [a]–[i] | 133/138 | 138/138 |
% correct: mean % (SD) | 96.4% (10.0) | 100% (0.0) |
Min./max. value in % | 66.7/100% | 100/100% |
IIb. Correct identification, control item contrast [ɐ]–[i] | 129/138 | 135/138 |
% correct: mean % (SD) | 93.5% (8.3) | 97.8% (5.7) |
Min./max. value in % | 83.3/100% | 83.3/100% |
III. Correct identification of the contrast [a]–[ɐ] | 179/276 | 246/276 |
% correct: mean % (SD) | 64.9% (22.9) | 89.1% (10.5) |
Min./max. value in % | 8.3/100% | 66.7/100% |
IV. Correct identification, distractor items (catch trials) | 75/92 | 74/92 |
% correct: mean % (SD) | 81.5% (20.3) | 80.4% (28.2) |
Min./max. value in % | 25/100% | 0/100% |
The overall accuracy rates in Table
If we look only at the control item contrasts ([a]–[i] and [ɐ]–[i]), we observe that both groups of speakers show high accuracy scores, indicating that the participants had no difficulties in conducting the task. The Braga speakers obtained 96.4% of correctness for the contrast [a]–[i] and 93.5% for the control item contrast [ɐ]–[i]; the Lisbon speakers reached 100% for [a]–[i] and 97.8% for [ɐ]–[i]. The Standard deviation is low for both speaker groups.
Now let us analyse the test sequences comparing the two target vowels [a] and [ɐ], i.e., the contexts where the target vowels have to be identified against each other. In these contexts, the results show that the identification rate is considerably lower for the Braga group (64.9%) compared to the Lisbon group (89.1%). Here we highlight the range between minimal and maximal scores in both groups. The minimal accuracy score in the Braga group is 8.3%, whereas the maximum score reaches 100%. Accordingly, the Standard Deviation reaches a score of 22.9 in the Braga group. In contrast, for the Lisbon group, the range and the Standard Deviation are between 66.7 and 100%; SD = 10.5. The difference between the two speaker groups is illustrated in the boxplot in Figure
Correct identification rate for the contrast [a]–[ɐ].
Finally, both groups show similar results for the catch trial items (see Table
For the statistical analysis, a binary logistic regression model was applied. The dependent variable was
Because the contingency coefficent in the test for collinearity (Cramér’s V) showed that
Cramér’s V contingency coefficient for values.
Value | Approximate Significance | ||
---|---|---|---|
Nominal by Nominal | Phi | 1.230 | .000 |
Cramer’s V | .710 | .000 | |
N of Valid Cases | 736 |
Hence, we included
Table
Results of the most accurate binary logistic regression model.
B | S.E. | Wald | df | Sig. | Exp(B) | |
---|---|---|---|---|---|---|
position of the target vowel | 6.090 | 3 | .107 | |||
target vowel | .134 | .183 | .536 | 1 | .464 | 1.144 |
consonantal context | .034 | .183 | .034 | 1 | .855 | 1.034 |
European Portuguese variety | –1.106 | .192 | 33.033 | 1 | .000 | .331 |
The main finding of the present study is the corroboration of existing dialectal differences between speakers of the Braga region and speakers of the Lisbon region when it comes to the discrimination between the two vowels [a] and [ɐ]. The speakers of the northern Portuguese variety differ from the speakers of the Littoral Center variety in identifying the vowel contrast under consideration, while all speakers perform similarly in the control conditions. Previous acoustic studies (e.g.,
As already discussed in section 2.2, the absence of the vowel contrast [a]–[ɐ] in the northern variety is restricted to stressed syllables, particularly to stressed open syllables followed by a nasal. The vowel [ɐ] is not totally absent from this dialect, since a similar vowel exists in unstressed syllables (e.g., in
It is also noteworthy to mention that the speakers of the Braga dialect show a high degree of intra- and interindividual variation. The ability of the northern dialect speakers to perceive the central vowel(s) is shaped by their exposure to their native dialect where the contrast [a] and [ɐ] is less prominent than in Standard Portuguese speech. However, they are also exposed to some extent to the vowel contrast [a] and [ɐ] when listening to speakers of the central variety (i.e., Standard EP). SEP is of course available to the speakers of the Braga variety as it is ubiquitous for instance in the media. This explains the high variation observed in the group of the northern dialect speakers: some speakers seem more familiar with the Standard dialect than others.
In sum, this study shows that speakers of two different EP varieties perform differently in discriminating the vowel contrast [a]–[ɐ] in a perception task. We presume that the underlying factor might be a difference in the status of [ɐ] in both varieties resulting in a different language acquisition situation. To support our assumptions concerning the status of [ɐ] in European Portuguese, further inquiry needs to be executed to compare the vowel inventories of the northern to the central and southern Portuguese variety. More studies on the contrast [a]–[ɐ] are required, including perception and production tests with different syllable structured test items, including unstressed syllables.
The authors have no competing interests to declare.
An alternative view has been advocated by Veloso (
Sociolinguistic Profile of Braga’s speech, cf. Barbosa (
Their study also revealed different F2 values for the two dialects: Braga speakers show lower F2 values than Lisbon speakers indicating that /a/ is produced more towards the front in Lisbon than in Braga.
See
The results of the other items will be analysed in a separate study, which includes an experimental group of L2 learners of EP.