Eskicioglu E, Taslica S, Guducu C, Oniz A, Ozgoren M. Effects of Voice Onset Time and Place of Articulation on Perception of Dichotic Turkish Syllables. Speech Communication. 2024 Dec 13:103170.
This study investigates how voice onset time (VOT) and place of articulation (POA) influence hemispheric specialization in speech perception, focusing on the Turkish language. Using dichotic listening tests, the research analyzed the responses of 95 right-handed native Turkish speakers. These participants were exposed to various consonant-vowel syllable pairs, differentiated by VOT (prevoiced vs. long VOT) and POA (bilabial, alveolar, and velar).
The findings revealed that prevoiced consonants were more dominant than those with long VOT, increasing the right ear advantage (REA) associated with left hemisphere specialization for speech processing. Velar consonants demonstrated higher dominance compared to bilabial and alveolar consonants. Moreover, when POA differed between stimuli, lateralization and error rates were notably affected. The study underscores the interplay between VOT and POA in shaping auditory processing and highlights unique characteristics of the Turkish language in this domain. Future research integrating neuroimaging methods is recommended to further explore these effects.
Dr. Murat Özgören, a professor at the Faculty of Medicine, Near East University, and Dr. Adile Öniz, a professor at the Faculty of Health Sciences, specialize in biophysics and cognitive neuroscience. Their research focuses on cognition, innovation, and brain biophysics, contributing to a deeper understanding of language and perception mechanisms.
Prof. Özgören and Prof. Öniz invite collaborations with researchers and institutions interested in auditory processing, language specialization, and cognitive neuroscience. For inquiries, please contact them at murat.ozgoren@neu.edu.tr and adile.oniz@neu.edu.tr
Abstract
Dichotic listening has been widely used in research investigating the hemispheric specialization of language. A common finding is the Right-ear Advantage (REA), reflecting left hemisphere speech sound perception specialization. However, acoustic/phonetic features of the stimuli, such as voice onset time (VOT) and place of articulation (POA), are known to affect the REA. This study investigates the effects of these features on the REA in the Turkish language, whose language family differs from the languages typically used in previous VOT and POA studies. Data of 95 right-handed participants with REA, which was defined as reporting at least one more correct right than left ear response, were analyzed. Prevoiced consonants were dominant compared with consonants with long VOT and resulted in increased REA. Velar consonants were dominant compared with other consonants. Velar and alveolar consonants resulted in higher REA than bilabial consonants. Lateralization and error rates were lower when POA, but not VOT, of the consonants differed. Error responses were mostly determined by the VOT feature of the consonant presented to the right ear. To conclude, the effects of VOT and PoA on the hemispheric asymmetry in Turkish have been spotted by a behavioral approach. Further neuroimaging or electrophysiologic investigations are needed to validate and shed light into the underlying mechanisms of VOT and PoA effects during the DL test.
