Biomechanics and vocal tract morphology

Transcription

1 Biomechanics and vocal tract morphology Pascal Perrier Gipsa-lab CNRS Grenoble University 1

2 Outline Introduction Some basics about biomechanics and orofacial biomechanics 2D and 3D models of the tongue and the face Biomechanics and control Inflluence of tissues stiffening on speech articulation (Pathology) Muscle direction variability, Palate morphology and articulatory control accuracy Variations in Orbicularis Oris implementation and lip protrusion. 2

3 Collaborators Project SPRECHArt (DFG - PI Susanne Fuchs) Ralf Winkler & Susanne Fuchs Project SkullSpeech (ANR) Mohammad Nazari, Guillaume Barbier, Yohan Payan Collaboration Gipsa-lab ArtiSynth (UBC Vancouver) Ian Stavness, Sydney Fels 3

4 Introduction Little studies about speaker-specific biomechanics and motor control Biomechanics: a constraint not a determining factor Models: provide information about the constraint Evaluation with experimental data requires models of motor control Comparison with data validates, contradicts hypotheses about motor control strategies Biomechanical models can suggest hypotheses about motor control 4

5 Biomechanics? Muscles anatomy: Which muscles? Which direction? On which part of body? Muscles mechanics Which maximum level of force? Central and feedback contribution to muscle activation Articulatory Dynamics (=Force representation) Which inertia (mass)? Which elasticity (Stiffness, Young and Shear Modulus)? Which damping? 5 Which interaction with external structures?

6 Specificity of oro-facial biomechanics: articulators are mainly soft bodies Force do not only generate displacement but also (and mainly) deformation (strain) Strain occurs in three directions and not only in the direction of the force 6 Nazari, M.A. (2011). PhD Grenoble University

7 Specificity of oro-facial biomechanics: articulators are mainly soft bodies Force Stress Displacement Strain Non-linear stress strain relation : Non constant stiffness : d(stress)/d(strain) (Young Modulus) 7 Nazari, M.A. (2011). PhD Grenoble University

8 Tongue anatomy Anatomical data 8 Netter, 2004 Takemoto, J. Speech Lang. Hear. Res., 2001,

9 2D Tongue Model Payan & Perrier, Speech Comm 1997 Perrier et al., JASA 2003 Posterior genioglossus Anterior Genioglossus Hyoglossus Styloglossus 9 Verticalis Inferior Longitudinalis,

10 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Posterior Genioglossus 10,

11 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Medium Genioglossus 11,

12 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Anterior genioglossus 12,

13 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Styloglossus 13,

14 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Hyoglossus 14,

15 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Verticalis 15,

16 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Transversalis 16,

17 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Geniohyoid 17,

18 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA 2009 Mylohyoid 18,

19 3D Tongue Model Gerard et al, 2006; Buchaillard et al., JASA

20 Face anatomy 20

21 3D Face model Nazari et al., CMBBE 2010 Implementation of macrofibers in reference to the skull 21,

22 3D Face model Nazari et al., CMBBE ,

23 Lip protrusion/rounding: Shaping by stiffening Nazari et al., Motor Control, 2011 Results 23,

24 Lip protrusion/rounding: Shaping by stiffening Nazari et al., Motor Control, 2011 Lip Parameters for Studying Speech Production 24 Abry & Boë, 1986

25 Lip protrusion/rounding: Shaping by stiffening Nazari et al., Motor Control, 2011 No stress-stiffening With stress-stiffening 25

26 Impact of tissue stiffening (Pathology) Normal stiffness 26

27 Impact of tissue stiffening (Pathology) Normal stiffness x 3 27

28 Impact of tissue stiffening (Pathology) Normal stiffness x 6 28

29 Impact of tissue stiffening (Pathology) Normal stiffness x 10 29

30 Variability in muscle orientation - YPM 30

31 Variability in muscle orientation - AV 31

32 Variability in muscle orientation - CS 32

33 Variability in muscle orientation [i] YPM Aire en cm** Muscle activations GGP GGA HYO STY Distance à la glotte en cm Ratio GGP/STY = 0.75

34 Variability in muscle orientation [i] AV Aire en cm** Muscle activations GGP GGA HYO STY Distance à la glotte en cm Ratio GGP/STY = 0.75

35 Variability in muscle orientation [i] CS Aire en cm** Muscle activations GGP GGA HYO STY Distance à la glotte en cm Ratio GGP/STY = 1.9

36 Variability in muscle orientation [i] YPM 100 Subject: ypm - F1-F2 plan (poles) 3600 Subject: ypm - F2-F3 plan (poles) F1 (Hz) 250 F3 (Hz) F2 (Hz) F2 (Hz)

37 Variability in muscle orientation [i] AV Subject: av - F1-F2 plan (poles) Subject: av - F2-F3 plan (poles) F1 (Hz) F3 (Hz) F2 (Hz) F2 (Hz)

38 Variability in muscle orientation [i] CS Subject: cs - F1-F2 plan (poles) Subject: cs - F2-F3 plan (poles) F1 (Hz) F3 (Hz) F2 (Hz) F2 (Hz)

39 Variability in muscle orientation [i] Main direction of formant variability for: YPM AV CS F1 F3 39 F2 Summary : AV has - the largest ration VarF2/VarF1 - the smallest VarF1 - the largest VarF3 F2 AV s tongue remains very close to the palate while moving backward

40 Variability in muscle orientation [i] YPM Constriction becomes more open but remains at the same location Subject:ypm Area (cm**2) Distance from glottis (cm) 40

41 Variability in muscle orientation [i] AV Constriction opens slightly and moves backward Subject:av Area (cm**2) Distance from glottis (cm) 41

42 Variability in muscle orientation [i] CS Constriction becomes more open but remains at the same location Subject:cs Area (cm**2) Distance from glottis (cm) 42

43 Variability in muscle orientation YPM GGP STY GGA HYO 43

44 Variability in muscle orientation AV GGP STY GGA HYO 44

45 Variability in muscle orientation CS GGP STY GGA HYO 45

46 YPM EFFECT of STYLOGLOSSUS Initial constriction region Same final constriction region 46 [i] at target Main direction of displacement associated with STY activation

47 AV EFFECT of STYLOGLOSSUS Initial constriction region New constriction region 47 [i] at target Main direction of displacement associated with STY activation

48 CS EFFECT of STYLOGLOSSUS Initial constriction region Same final constriction region 48 [i] at target Main direction of displacement associated with STY activation

49 First conclusion Muscle orientation influences the relation between motor commands and spectral patterns Does it influence the acoustic speaker-specific variability. Does it nfluence motor control strategy/accuracy? 49

50 A related issue : palate shape and articulatory variability Brunner, Fuchs and Perrier, JASA 2009 Basic idea : For a flat palate of local variation of the tongue position will induce more change in the cross-sectional area More change in the acoustical domain. Flat palate Domeshaped palate 50

51 Palate shape and articulatory variability Brunner, Fuchs and Perrier, JASA 2009 Measure of palate curvature in the coronal plane : α a high -value corresponds to a flat palate and a low value to a domeshaped palate. 51 Measure of articulatory Variability with EPG: COG & Number of contacts.

52 Palate shape and articulatory variability Brunner, Fuchs and Perrier, JASA 2009 Articulatory variability (32 speakers) 52

53 Palate shape and articulatory variability Brunner, Fuchs and Perrier, JASA 2009 Acoustical variability (32 speakers) 53

54 Conclusion Speakers tend to adapt their articulatory variability to the coronal shape of the palate in order to preserve the acoustic correlates of a good perception of the phoneme. 54

55 Variability in muscle orientation and palate shape Consequences for speech production and speech perception Obviously: inter-speaker differences in the required accuracy in motor control Probably: inter-speaker differences in co-articulation patterns and in the influence of speaking rate variation Possibly: inter-speaker differences in perceptual sensitivity to local acoustical variations (Shiller et al., JASA, 2009) 55

56 Shiller, Sato, Gracco, Baum (2009) Perceptual recalibration of speech sounds following speech motor learning. Perturbation of the auditory feedback /s/ versus // Group 1 /s/ Group 2 /s/ Group 3 /s/ Decrease of the centroid 56

57 Shiller, Sato, Gracco, Baum (2009) Shift of the perceptual /s/-// boundary Group 1 Group 2 Group 3 Perceptuomotor adapation 57 Selective adaptation No effect

58 Variability in muscle orientation and palate shape Consequences for speech production and speech perception Obviously: inter-speaker differences in the required accuracy in motor control Probably: inter-speaker differences in co-articulation patterns and in the influence of speaking rate variation Possibly: inter-speaker differences in perceptual sensitivity to local acoustical variations (Shiller et al., JASA, 2009) 58 A high sensitivity of speech spectral patterns to motor variability increases the intolerance to motor vatiability and in turn could increase the acuity of speech perception in this region.

59 Variation in orbicularis oris implementation and lip protrusion Stavness, Nazari, Perrier, Demolin, Payan, JSLHR, 2013 Karitiana speaker: vowel [o] [koβot], sweet. (Courtesy of Didier Demolin) 59 French: vowel [u] (Courtesy of Pierre Badin)

60 Variation in orbicularis oris implementation and lip protrusion Stavness, Nazari, Perrier, Demolin, Payan, JSLHR, 2013 Modeling variation in OO Implementation 1,2,3,4: marginal to peripheral S,M,D: Superficial to depth 60

61 Variation in orbicularis oris implementation and lip protrusion Stavness, Nazari, Perrier, Demolin, Payan, JSLHR, 2013 Example of OO Implementation M3 61

62 Variation in orbicularis oris implementation and lip protrusion Middle and peripheral implementation generates protrusion and rounding 62

63 Variation in orbicularis oris implementation and lip protrusion Stavness, Nazari, Perrier, Demolin, Payan, JSLHR, 2013 Differences in peripheralness between upper And lower lips 63

64 Conclusion Variations across populations in the world on the Orbicularis Oris implementation could contribute to explain some aspects of the phoneme distributions in the world languages as well as the variation of the phonemic characteristics across languages and their diachronic evolution. Inter-individual variations with a population in the OOS and OOI implementation could determine variation in the protrusion and rounding gestures Coarticulation 64

65 To know more 65

66 To know more 66

67 Thank you 67,