PHONETOTOPIC ORGANIZATION OF PHONATION EVIDENCE FROM ELECTROPHYSIOLOGY, AERODYNAMICS, ACOUSTICS AND KINESTETICS Krzysztof Izdebski Pacific Voice and Speech Foundation San Francisco, CA, USA

1: Presentation of a neurophysiologic model of phonation organization 2: Propose voice pitch pattern predictability 3: Provide evidence for understanding of phonation training and disordered phonation processes.

Method: Data from electromyographic, aerodynamic, kinesthetic and acoustic signals acquired simultaneously during the production of phonatory ranges, intensities and reaction times.

Hooked-wire bipolar electrodes were inserted bilaterally to TA, IA, LCA, CT, ST, TH muscles with simultaneous recordings of Ps, Af, Pio and voice

Tasks included full glissando and varied intensity ranges, speech containing selected segments comprising loaded, voiceless and random segments Phonation was initiated at various lung volumes (MCE, Full and Residual LV)

Tasks included phonatory RTs arranged in the matter of complexity to reflect cortial organization and peripheral components i.e. vowel, syllables, words with progressive complexity, (v, vic, vicar, vicerage…)

RTs were elicited in 1: subject own condition 2: on air flow 3: on breath holding Auditory, Visual and Somesthetic Stimuli were used at randomized pre-stimulus intervals between 200 and 3000 msec

Experimental cohort varied from 1 to 15 subjects depending on tasks complexity and medical conditions

Vertical Larynx Position motion were tracked with lateral filming and profile motion was digitized for up and down deviations from rest as a function of Fo and dB Both untrained and trained subjects participated

Results

From these data a model of phonatory organization was constructed, termed “Phonetotopic model of phonation.”

Results: It was found that human voice pitch production follows a predictable pattern. This pattern follows phonetotopic organization of all intrinsic and extrinsic laryngeal muscle activity corresponding to given pitch, intensity and quality targets.

Vertical Larynx Position (VLP)

RT = 130 msec 60 msec cortical time 30 msec efferent time msec muscle contration time

XVI PVC PVSF/UCLA

Tremor vs ADDSD

Conclusions: Based on this phonetotopic organization, voice pattern deviations are predictable and consequently indicative of voice conditions present in the various vocal pathologies and/or during artistic training.

Therefore, when examining voice production by referring observations to phonetotopic patterns, an unequivocal description of any phonation is possible. Accordingly, pitfalls or deficits of phonation production will correspond in an organized fashion to the specific conditions observed.

Depending upon these conditions, phonation patterns will differ with organic (mucosal), neurologic (motility), traumatic (motility and mobility) and/or functional dysphonias including malingering, or when the subject is undergoing vocal training.

References: Izdebski, K. Clinical Voice Assessment: The Role & Value of the Phonatory Function Studies. Chapter 29, In Lalwani, A. K. (ed.) Current Diagnosis & Treatment in OTOLARYNGOLOGY-HEAD & NECK SURGERY, Lange Medical Books/McGraw- Hill, New York, 3rd Edition, 2011

This research was conducted with Dr. Thomas Shipp and this Model is dedicated to him

The End