Trevisan, M. A. | bioRxiv Science

bioRxiv2019

Ocular dynamics reveal articulatory processing at single-phoneme level during silent reading

Silent reading is a cognitive operation that produces verbal content with no vocal output. One relevant question is the extent to which this verbal content is processed as overt speech in the brain. To address this, we investigated the signatures of articulatory processing during reading. We acquired sound, eye trajectories and vocal gestures during the reading of consonant-consonant-vowel (CCV) pseudowords. We found that the duration of the first fixations on the CCVs during silent reading are correlated to the duration of the transitions between consonants when the CCVs are actually uttered. An articulatory model of the vocal system was implemented to show that consonantal transitions measure the articulatory effort required to produce the CCVs. These results demonstrate that silent reading is modulated by slight articulatory features such as the laryngeal abduction needed to devoice a single consonant or the reshaping of the vocal tract between successive consonants.

neuroscience↗

bioRxiv2017

Discrete anatomical coordinates for speech production and synthesis

The sounds of all languages are described by a finite set of symbols, which are extracted from the continuum of sounds produced by the vocal organ. How the discrete phonemic identity is encoded in the continuous movements producing speech remains an open question for the experimental phonology. In this work, this question is assessed by using Hall-effect transducers and magnets -mounted on the tongue, lips and jaw- to track the kinematics of the oral tract during the vocalization of vowel-consonant-vowel structures. Using a threshold strategy, the time traces of the transducers were converted into discrete motor coordinates unambiguously associated with the vocalized phonemes. Furthermore, the signals of the transducers combined with the discretization strategy were used to drive a low-dimensional vocal model capable of synthesizing intelligible speech. The current work not only addressed a relevant inquiry of the biology of language, but also shows the performance of the experimental technique to monitor the displacement of the main articulators of the vocal tract while speaking. This novel electronic device represents an economic and portable option to the standard system used to study the vocal tract movements.

neuroscience↗