Speaking Fundamental Frequency Differences
in Highly
Proficient German-English Bilinguals
Scharff Rethfeldt, W. (
Introduction
This research concerns a
cross-language study of speaking fundamental frequency (SFF). There has been a
limited amount of work on this before (Hanley and Snidecor, 1967; Braun, 1994;
van Bezooijen, 1995). One of the perennial problems involves how does one
assure precise matching of age, gender, habitual voice characteristics, and so
forth. We proposed to solve this by examining SFF across languages in highly
proficient bilingual speakers. Because the samples gathered for the two
languages come from the same speaker, exact matching is assured.
So far, there are a very limited
number of main studies published concerning SFF in bilingual subjects (Braun
1994; Altenberg and Ferrand 2006). Another was published only as an abstract by
Wardrip-Fruin (1989). Braun as well as Wardrip-Fruin found no significant
differences between the SFF of the bilinguals’ two languages. Altenberg et al
found significantly higher fundamental frequencies in their subjects when
speaking Russian compared to English. By contrast there was no significant
change across languages for their bilingual English-Cantonese speakers. The
present study extends these investigations using laryngographic assessment to
control for confounds observed in previous studies on SFF (e.g. SFF established
on acoustical recordings only).
The key effect of bilingualism concerning this study is the fact that at least two languages are in contact within the same person. Due to this factor, it has been assumed that one language (L1) has an influence on the other (L2), and that this influence may be bidirectional, since the L2 may also have an effect on the L1 (Bruyninckx et al., 1994).
Hence, in this investigation the
question was, assuming that there are cross-linguistic differences, whether
there is also a within-speaker difference. Could it be that in speaking and/or
reading, the vocal characteristics of the L1 are carried over into the L2 and
thus affect SFF? A further question concerned whether a bilingual speaker's
fundamental frequency is dependent on the speaker himself and therefore
independent from the spoken language in general, or, whether the SFF across languages
is different, dependent on the language spoken.
Method
SFF was compared for 12 highly
proficient female speakers of German and English aged 20-40 years. Their SFF
were compared to 12 monolingual German and 12 monolingual English controls,
matched on age, gender, non-smoking and absence of laryngeal dysfunction.
Subjects were asked to read a
balanced text (oral reading) and to tell a given joke (directed speech).
Responses were recorded and digitised using a laryngograph, which detected
directly the vibratory cycles of the vocal folds and thereby the median SFF
value. The SFF values were established for each subject and language in order
to calculate the average SFF group values for all speakers. These were then
used in the data analysis, using two-way mixed design ANOVAs.
Results
Table 1: SFF group mean values in
Hertz.
|
Group |
SFF joke (in Hertz) |
SFF text (in Hertz) |
|
German monolinguals |
194.6 (range 136.5 - 299.7) |
204.3 (range 160.2 - 275.1) |
|
English monolinguals |
316.7 (range 228.0 - 515.8) |
279.2 (range 238.9 - 388.3) |
|
Bilinguals speaking German |
258.6 (range 199.0 - 419.3) |
250.0 (range 201.4 - 336.3) |
|
Bilinguals speaking English |
270.3 (range 202.1 - 443.3) |
258.8 (range 210.0 - 357.3) |
Table 1 summarises the results.
There are clear cross-language differences in SFF. Monolingual speakers of
German differed significantly from the monolingual English speakers
(p<0.0001), using a generally lower SFF and speaking with less variation
than their monolingual English speaking counterparts.
The bilingual speakers showed significant
differences between their two languages for mean SFF (p=0.008), using a higher
pitch when speaking English compared to when speaking German. Comparing the
results of the bilingual speakers with their monolingual counterparts on their
two languages, significant differences in SFF were revealed, with the bilingual
speakers demonstrating mean SFF intermediate to these.
Discussion
The data from the monolingual
speakers of German and English revealed a clear cross-language difference in SFF.
Cross-language differences were found in the bilingual speakers too,
demonstrating that the differences are not just an artefact of group selection
and matching. The bilingual speakers seem to use two different SFFs for each
language. However, in neither language did bilingual speakers achieve
monolingual production in terms of SFF. The bilingual speakers using German
appeared to compromise to English in that they raised their pitch and used a
higher SFF for directed speech than for oral reading. However, they seem to
move towards German values when speaking English, in that they lower their
pitch and speak with less variation in the two tasks.
The present data suggest that SFF is
language-specific and may be considered in terms of an articulatory setting for
paralinguistic purposes, acting as a marker of linguistic group membership.
Further investigations might reveal how this relates to identity of a bilingual
speaker.
Implications from the present findings can be
drawn from different perspectives. From the socio-cultural view, the use of
non-native-like SFF may cause listeners to misjudge a bilingual speaker's
affective state, since it has been proven that different SFFs evoke different
reactions in listeners. Regarding the aspect of forensic issues, it is
important to consider that a bilingual speaker's SFF differs from monolingual
norms of his languages, especially when considering the forensic use of the
aspect of SFF for speaker identification and speaker verification.
Regarding voice therapy, speech and
language therapists and ENT specialists need to account for the different SFF
of bilingual speakers e.g. in that they consider that there is no SFF norm
value and thus a bilingual cannot be assessed and/or treated based on
monolingual standards. This is especially important if a higher SFF might be
considered as not physiological in one of the languages. Finally, considering
the area of second language learning, SFF might be considered as an additional
cue in order to achieve L2-competence, since the acquisition of an appropriate
articulatory setting may ease the learning of the L2-prosody. In the case of
less proficient bilingual speakers we might have expected different results to
the present ones, in as far as one would predict dominant language SFF patterns
in the L2, and this would alter towards monolingual values for L2 as the
speaker became more proficient.
Literature
Altenberg E., Ferrand C. (2006) Fundamental
frequency in monolingual English, bilingual Russian/Englsh, bilingual Chinese
English young adult women, Journal of
Voice, 20, 89-96
Braun (1994) Sprechstimmlage und Muttersprache, Zeitschrift für Dialektologie und Linguistik, LXI. Jahrgang, Heft 2, pp. 170-178
Bruyninckx et al. (1994)
Language-induced voice quality variability in bilinguals, Journal of
Phonetics, vol. 22, no. 1, pp. 19-31
Hanley and Snidecor (1967) Some Acoustic
Similarities among Languages, Phonetica, vol. 17, pp. 97-107
Van Bezooijen (1995) Sociocultural Aspects of
Pitch Differences between Japanese and Dutch Women, Language and Speech,
vol. 38, no. 3, pp. 253-265
Wardrip-Fruin (1989) Vocal fundamental
frequency: Variation by language, language group, and sex, Journal of the
Acoustical Society of
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