Recent Research Activities
2021-2022: French prosodic stress produced by Twi speakers compared to French speakers. French Prosodic Stress is acoustically related to a combination of duration, fundamental frequency (f0) and intensity. This work involves a comparative study investigating the use of these correlates by French native speakers (FS) and Twi speakers (TS) learning French. In a production experiment, their readings were recorded in a studio and analyzed with a sound Editor. Durational, intensity and fundamental frequency values were extracted for each of the selected target syllables. DAW (digital audio workstation) used in executing the production is Steinberg Cubase 5 for both recordings and mixing. Evidence from the acoustic data show that the most important acoustic parameter in producing French prosodic final stress, by both native speakers and Twi learners of French, is duration which is consistent. Pitch difference (f0) and intensity are not the key determining factors in distinguishing prosodic stress differences between penultimate and final syllables.
Presentation & Article: French prosodic stress produced by Twi speakers compared to French speakers: an acoustic investigation. Proceedings of the 20th International Congress of Phonetic Sciences. Prague, Czech Republic, 7-11 August. 2023, (pp. 2766 - 2770).
https://guarant.cz/icphs2023/1105.pdf
2018-2019: How native speakers of French, a non-tone language with different lexical stress properties, perceive two Twi lexical tones in a series of monosyllabic contrasting words. They are words produced, first in isolation and second, in a carrier sentence. Three experiments were conducted. Experiment 1 tested identification of tone contrasts by native speakers of Twi. Experiment 2 tested native French speakers’ identification of tones presented in isolated context and Experiment 3 tested identification of tones presented in a carrier sentence. Acoustic investigations show that pitch difference is the determining factor in distinguishing high and low tone contrasts in Twi. Findings imply that linguistic experience with non-native tones does not necessarily preclude tone perception. Results also show that the identification rate of tones in an isolation context was higher than the identification rate of tones in a carrier sentence context.
Presentation & Article: Non-native Speakers’ Identification of Lexical Tone Contrasts, Proceedings of the 19th International Congress of Phonetic Sciences. Melbourne, Australia, 2019, (pp. 2782-2786). Canberra, Australia: Australasian Speech Science and Technology Association Inc.
https://assta.org/proceedings/ICPhS2019/papers/ICPhS_2831.pdf
2016-2017: Contribution to the Illustrations of the International Phonetic Alphabet. This contribution will be the first Ghanaian Language (Twi) to appear in the series of more than 110 languages. Illustrations will be accompanied at the time of submission by high-quality recordings (preferably WAV files) with at least a 22 kHz sampling rate, of all words and narrative text in the target language occurring anywhere in the illustration. Acoustic recordings are made at 44.1 kHz sampling frequency or higher, and with a bit-rate of 16 bits or higher.
2015: The behaviour of vowel quantity contrasts when speaking rate is increased and durations tend to be compressed. What is the effect of speaking rate on the compression and expansion of segment durations in Non-Pathological Perturbed Speech?
Presentation & Article: Phonemic Quantity Contrasts in Normal and Non-pathological Perturbed Speech. In The Scottish Consortium for ICPhS 2015 (Ed.), Proceedings of the 18th International Congress of Phonetic Sciences. Glasgow, UK: the University of Glasgow. ISBN 978-0-85261-941-4. Paper number 0715.1-4.
2015: The behaviour of vowel quantity contrasts when speaking rate is increased and durations tend to be compressed. What is the effect of speaking rate on the compression and expansion of segment durations in Non-Pathological Perturbed Speech?
Presentation & Article: Phonemic Quantity Contrasts in Normal and Non-pathological Perturbed Speech. In The Scottish Consortium for ICPhS 2015 (Ed.), Proceedings of the 18th International Congress of Phonetic Sciences. Glasgow, UK: the University of Glasgow. ISBN 978-0-85261-941-4. Paper number 0715.1-4.
2014: Relationship between ATR Vowel Harmony and Vowel Quality in Twi.
Presentation: ATR Vowel Harmony and Vowel Quality: Are They Related? 45th Annual Conference on African Linguistics, University of Kansas April 17-19, 2014. Theme: “Africa’s Endangered Languages: Documentary and Theoretical Approaches”.
2013-2014: The effects of Lexical Tone Contrasts on Vowel Quality. Acoustic measurements carried out to investigate for differences between vowel quality in the two phonological (High Tone/Low Tone) categories. Fundamental frequency values as well as formant values (F1, F2, F3 and F4) examined to determine qualitative differences between the two phonological classes.
Article: Relationship between Lexical Tone Contrasts and Vowel Quality, European Scientific Journal, vol. 10, No. 17: 418-428, 2014.
2011: Speech Perception: Discrimination of Twi Lexical Contrasts based on Tones by Native French Speakers.
Article: Discrimination des tons lexicaux du twi par des locuteurs français, ed. R. Sock, N. Moritz, A. Hamm, Revue des Recherches Anglaises & Nord-Américaines (RANAM), Hors Série, Service des Publications et Périodiques, Université de Strasbourg : 83-90, 2011.
2010-2011: Speech Production: Nasal-Oral Contrast of Short and Long Vowels in Twi. Acoustic analyses undertaken to compare the production of oral and nasal vowels in both the short and long categories. Durational analyses of oral and nasal short/long vowels are made. Formant structure investigations are undertaken for the two phonological classes.
Article: Nasal-Oral Contrast of Short and Long Vowels in Twi: An Acoustic Study, Selected Proceedings of the 40th Annual Conference on African Linguistics, ed. Eyamba G. Bokamba et al., 95-104. Somerville, MA: Cascadilla Proceedings Project, 2011.
Other Research Activities
Speech and Language Science Research Group Langues et Parole (LiLPA), Composante Parole & Cognition EA 1339, Phonetics Institute of Strasbourg, University of Strasbourg, France. Major research areas are Experimental Phonetics and Phonology, Contrastive Phonology, Speech Production, Perception & Segmentation and Second Language Acquisition, Programmatic Research on the Twi Language: 2000-2010.
Centre National de la Recherche Scientifique (CNRS), Délégation Alsace, Assistant en production et analyse de données: The French National Centre for Scientific Research, Data Production and Analysis: February-March 2010.
Centre National de la Recherche Scientifique (CNRS), Délégation Alsace, Assistant en production et analyse de données: The French National Centre for Scientific Research, Data Production and Analysis: June-July 2009.
Centre National de la Recherche Scientifique (CNRS), Délégation Alsace, Assistant en production et analyse de données: The French National Centre for Scientific Research, Data Production and Analysis : May-June 2008.
French Ministry of Research and New Technologies: Data base Project n° ACI –TTT.
Participant at the Phonetics Institute, University of Strasbourg, France.
Project title: Elaboration of a multimedia platform for analysing and promotion of X-ray films data on speech production and perception made at the Strasbourg Institute since the 1950s. The project dealt with 20 films concerning various linguistic aspects of languages spoken in Africa, Europe,
Asia and Latin America.
Date: 2005 to 2008.
Duration: 36 months.
Upper Rhine (Rhin Supérieur) INTERREG III DANOK Project n° 4b 11.
Participant at the Phonetics Institute, University of Strasbourg, France.
Project title: Data base, digitizing and preparation for archiving and broadcasting of rare X-ray films made over several years at the Strasbourg Institute related to cultural projects of the Upper Rhin Region. The films cover a wide variety of languages (10 African, 1 Latin American, 5 Asian, 6 European including French).
Project realization zone: France, Switzerland, Germany.
Date: July 2006 to September 2007
Duration: 15 months.
Acoustic Properties of Nasal Vowels: 2006.
Preliminary Study: Relationship between Tone Contrasts and Vowel Quality: 2006.
+ATR vs. –ATR Nasal Vowel Harmony: 2006.
Preliminary Study: Relationship between Advanced Tongue Root (ATR) Vowel Harmony and Vowel Quality: 2005-2006.
Vowel Quantity Contrasts: Evidence from Twi Nasal Vowels: 2005.
Duration and Quality in the Production of Oral and Nasal Vowel Length Contrasts: 2005.
Advanced Tongue Root (ATR) Vowel Harmony: 2004.
Motor Control in Speech Production and the Perceptual Efficiency of Anticipatory Gestures: Acoustic Data Analysis of Labialized Vowels: 2004.
French Ministry of Research and New Technologies: Cognitive Project n°ACT 1b.
Participant at the Phonetics Institute, University of Strasbourg, France.
Project title: Motor Control in Speech Production and Perception of Anticipatory Gestures.
Date: 2001 to 2003.
Duration: 24 months.
Preliminary Study: Relationship between Vowel Quantity and Vowel Quality: 2003.
Vowel Quantity Contrasts: An Acoustic investigation of Twi Oral Vowels: 2003.
A Cross-Language Study of Phonemic Frequency in Twi, French and English: 2002.
Phonemic Frequency in French and Twi with a View to a Didactics Application: 2001.
Vowel Quantity Contrasts in Twi: The Three Extreme Vowels of the Vowel Triangle: 2000.