Asymmetry of Occupational Noise Induced Hearing Loss: An Electrophysiological Approach.

 The question as to whether occupational noise exposure causes symmetrical or asymmetrical hearing loss is still controversial and incompletely understood.  Two electrophysiological methods (cortical evoked response audiometry: CERA and auditory steady state responses: ASSR) were used to address this issue.  156 subjects with a well-documented history of noise exposure, a wide range of noise induced hearing loss (NIHL) and without middle ear pathology underwent both a CERA and an ASSR examination in the context of an exhaustive medicolegal expert assessment intended for possible compensation.

Vocal Fold Collision Speed in vivo: The Effect of Loudness.

Mechanical impact stress on the vocal fold surface, particularly when excessive, has been postulated to cause the so-called phonotraumatic tissue lesions, such as nodules and polyps. The collision stress between the vocal folds depends on the vocal fold velocity at the time of impact. Hence this vocal fold collision speed is a relevant parameter when considering biomechanical economy of phonation, especially in voice professionals needing a louder voice than normal.

Dynamics of the Driving Force During the Normal Vocal Fold Vibration Cycle.

Intraglottal pressure is the driving force of vocal fold vibration. Theoretically, simultaneous quantification of glottal area and transglottal airflow allows the calculation of the intraglottal pressure waveform during a single vibration cycle. In this study, we show that, by combining photoglottography (transglottal light transmission) and airflow (Rothenberg mask) measurements during sustained vocal emissions in vivo, the intraglottal pressure wave can be approximated in a way similar to what has been done in models.

Nonorganic habitual dysphonia and autonomic dysfunction.

The present study was designed to test the hypothesis that there is a relation between nonorganic habitual dysphonia and subjective experience of dysfunction of the autonomic nervous system (neurovegetative lability). Eighty-three patients (65 women and 18 men) with a nonorganic voice disorder and a matched control group answered a questionnaire of 46 questions. One question replicated in different terms and six nonrelevant questions point out that the inquiry forms were answered in a consistent way.