Fig 1.
Relationship between fundamental frequency (fo) and subglottic pressure (psub) for phonation of different pitches.
Table 1.
Description of hypothesis A-D.
Table 2.
Subject number, age, gender, voice classification, classification according to the Bunch and Chapman [30] taxonomy, vital capacity (= VC), forced expiratory volume in one second (= FEV1), body height and weight.
Fig 2.
Musical notes and fundamental frequency (fo) for task 1 and 2 for each voice classification group.
Fig 3.
Measured distances in the sagittal (A) and coronal (B) plane and their definition according to anatomical landmarks. See also Table 2. DPHant = diaphragm anterior, DPHmed = highest point/ medial part of diaphragm, DPHpost = diaphragm posterior, ApDThorax = anterior-posterior diameter of the lung, ApDDPH = anterior-posterior diameter from DPH cupola to the back, DPHright = diaphragm right, DPHleft = diaphragm left.
Table 3.
Anatomical definition of distances in the sagittal and coronal planes.
Fig 4.
Definition of jump-time-point and–window.
The jump-time-point (tjump) was defined as 50% of fo differences between two different pitches. The jump-time-window was created by including 4 frames before and after tjump (t—4 to t4). Then mean values of distance parameters were evaluated and the mean gradient during 8 timesteps (m1-8) was derived for statistical analysis.
Fig 5.
Pitch correlates with Open Quotient (OQ), subglottic pressure (psub), Sound Pressure Level (SPL) and quotient of psub/SPL.
OQ, psub, SPL and psub/SPL taken from segments of sustained phonation of each pitch are displayed for each subject and task. Solid line, left side = task 1, dashed line, right side = task 2. Gender is marked with colour (red = female, blue = male). Green lines represent mean values. Please note that individual data points are presented connected for better tracing of individual points but the data points were extracted from parts of sustained phonation and not during the jump.
Fig 6.
Representative example curve of distance values (subject 2) with sudden inversions of curve gradient coincident with pitch jumps downwards.
Distance values are displayed in cm for all measured parameters of a sagittal image slice while singing task 1 (left) and 2 (right). Below, the corresponding spectrograph is displayed, and pitch is marked. Individual data of all subjects is displayed in S1 and S2 Figs.
Fig 7.
Less negative mean curve gradient during downwards jumps.
Gradient of movement curves during jump-time-window are displayed for upward jumps (red) and downward jumps (blue) including standard error.
Fig 8.
Differences in movement patterns for pitch jumps between different parts of the breathing apparatus.
Mean distance curves of all subjects are displayed for jump-time-windows at all measured locations. Numbers in the upper left corner mark the order of the jumps. Additionally, mean differences in Open Quotient (ΔOQ), subglottic pressure (Δpsub), sound pressure level (ΔSPL) between the two fundamental frequencies are displayed in the right section, including standard error.
Fig 9.
Maximum gradient (mmax) is higher for posterior diaphragm (DPHpost) and anterior movement of the diaphragm cupola (apDDPH) compared to all other parts of the respiratory system.
mmax is displayed for downwards jumps with standard errors. Significant differences are marked (* < .05), for all p-values see S1 Table.
Fig 10.
Lower mean gradient during upwards jumps for thorax diameter (apDThorax).
Mean gradient during the jump window for upwards jumps at different locations with standard deviation is displayed. Significant differences are marked (* < .05), for all p-values see S1 Table.
Fig 11.
Gradient change at high-medium jumps was pronounces compared to medium-low jumps, while no difference occurred between early and late jumps.
Mean gradient curves (all subjects and all distance parameters) for different jump events are displayed. High-medium and medium-low jumps are displayed left (A), early and late jumps are displayed right (B).