Research Note: Vocal Attack Time-Extended Analysis.

Normative data for vocal attack time (VAT) have previously been presented, but descriptive statistics and assessments of statistical significance of differences have previously been based on a data corpus that included both negative- and positive-valued VATs. Negative VAT values denote a glottal vocal attack, but, at the present time, the signification of the magnitude of a negative VAT value is unknown. The magnitude of a positive VAT value, on the other hand, conveys useful information about glottal behavior at the time of voice onset and is much more likely to be of use, especially in the clinical domain.

Effect of Voice Onset Type on Vocal Attack Time.

Vocal attack time (VAT) is the time lag between the growth of sound pressure (SP) and electroglottographic (EGG) signals at vocal initiation. The characteristics of voice initiation are associated with issues of vocal hygiene, efficiency, and quality. Vocal onsets have commonly been qualitatively characterized into three types: hard, simultaneous, and breathy.

Effect of fundamental frequency at voice onset on vocal attack time.

Objective: To examine vocal attack time (VAT) values associated with the production of low, mid, and high rates of vocal fold vibration in normal speakers.

Study Design: Sound pressure (SP) and electroglottographic (EGG) recordings were obtained for eight female and five male subjects while producing multiple tokens of the sustained vowels /ɑ/, /i/, and /u/ at comfortable loudness and at mid, low (-3 semitones), and high (+6 semitones) rates of vocal fold vibration.

Methods: Generalized sinusoidal models of the SP and EGG signals were computed to compare rates of amplitude change.

Vocal release time: a quantification of vocal offset.

Objective: To determine the vocal release time (VRT) for linguistically unconstrained voice offsets in a healthy young adult population.

Study Design: Sound pressure (SP) and electroglottographic (EGG) recordings were obtained for 57 female and 55 male subjects while producing multiple tokens of three tasks (sustained /ɑ:/, "always," and "hallways") at comfortable pitch and loudness.

Methods: SP and EGG signals were digitally time reversed and generalized sinusoidal models of the SP and EGG signals were obtained to compare rates of amplitude change.

Measures of vocal attack time for healthy young adults.

Objective: To determine the vocal attack time (VAT) in a healthy young adult population.

Study Design: Sound pressure (SP) and electroglottographic (EGG) recordings were obtained for 57 female and 55 male subjects while performing multiple tokens of three tasks (sustained /a/, "always," and "hallways") at comfortable pitch and loudness.

Methods: Generalized sinusoidal models were obtained for SP and EGG signals to compare rates of amplitude change.

A figure of merit for vocal attack time measurement.

Objectives: To develop and evaluate a figure of merit (FOM) for the measurement of vocal attack time (VAT) for sustained /a/. The FOM assesses a critical assumption of vocal startup on which the VAT measure is based and therefore represents integrity of the derived measure.

Methods: Pearson's correlation coefficient (0 ≤ |r| ≤ 1) was determined from amplitude features of sound pressure (SP) and electroglottographic (EGG) signals (n=1,033 tokens) to serve as a candidate FOM for the study.

Validation of a glottographic measure of vocal attack.

The speed with which the vocal folds adduct to the midline is considered an important variable in the etiology of some voice disorders and may also be a meaningful indicator of central or peripheral neural dysfunction. It is proposed that the time lag between the rise of the sound pressure (SP) and electroglottographic (EGG) signals, measured at the onset of phonation, provides a useful index of vocal attack time. This report describes the experimental validation of this measure, whereby the SP and EGG signals were recorded synchronously with high-speed videoendoscopy, from which a digital kymogram was generated.