OBJECTIVES The McGurk-MacDonald illusory percept is obtained by dubbing an incongruent articulatory movement on an auditory phoneme. This type of audiovisual speech perception contributes to the assessment of theories of speech perception. The mismatch negativity (MMN) reflects the detection of a deviant stimulus within the auditory short-term memory and… (More)
This paper describes the real-time MRI technique and its use for the study of speech production. The two major problems, (i) the simultaneous recording of the MR images and the speech signal and (ii) the synchronisation of the images and of the speech signal, are addressed. Measurement accuracy on real-time images is evaluated by comparison with similar… (More)
Amplifying communication is a characteristic of group-living animals. This study is concerned with food recruitment by chemical means, known to be associated with foraging in most ant colonies but also with defence or nest moving. A stochastic approach of collective choices made by ants faced with different sources is developed to account for the… (More)
M.R.I. techniques have been used to describe velum opening of French vowels. Data based on 18 joined axial slices of 4 mm thickness were recorded with two subjects. Differences in vclum opening are calculated from areas measured in the tract between the lowered velum and the back pharynx wall. A 3 D modelling of this tract is also proposed.
Magnetic Resonance Imaging techniques are uniquely attractive in their ability to provide an extensive body of information on the vocal tract geometry. Once the images are acquired, they must be further processed in order to segment the airway from the surrounding tissues, so as to locate the air passage. This problem has been addressed in several ways i n… (More)
This paper presents a comparative study of transformations used to compute the area of cross-sections of the vocal tract from the mid-sagittal measurements of the vocal tract. MRI techniques have been used to obtain both mid-sagittal distances and cross-sections of the vocal tract for French oral vowels uttered by two subjects. The measured cross-sectional… (More)
Recent studies have shown that MRI techniques are reliable to measure mid-sagittal cuts of the vocal tract. Three-dimensional images of the vocal tract have been proposed e.g. by Foldvick et al. ,  but despite this advance, these images do not offer any accurate measurement of sagittal cuts or area functions. Advance in MRI performances allows to… (More)
MRI techniques have been used to describe velum opening of French vowels. Data based on 18 joined axial slices of 4 mm thickness were recorded with four subjects. Differences in velum opening are calculated from areas measured in the tract between the lowered velum and the back pharynx wall. Results show that for all subjects, the back vowel [symbol: see… (More)