Exam 2 Part 10 Flashcards
Cycle-to-cycle variability in a signal (typically measured from sustained vowel productions or “extracted” vowels from connected speech).
Perturbation measures
Cycle-to-cycle variability in frequency
Jitter
Cycle-to-cycle variability in amplitude
Shimmer
Normal voice or mild impairment, might not include obvious deviations or distortions, acceptable for perturbation analysis
Type 1 voice
Disordered or desired productions, 2 different robust peaks, aperiodicity or variability results in multiple or variable fundamental frequency, Unreliable acoustic perturbation analysis; may depend on spectral analysis or other displays
Type 2 voice
Severely impaired voice, Aperiodicity or variability results in no identification of fundamental frequency, Not suitable for acoustic analysis, but may rely on auditory-perceptual judgments.
Type 3 voice
Ratio of periodic (or harmonic) signal energy to the aperiodic or noise energy in the voice waveform.
Harmonic (signal) to noise ratio (HNR)
Do normal voices have a high or low HNR?
High
Do dysphonia voices have a high or low HNR?
Low
Why do normal voices have a high HNR?
Mostly periodic and high signal/harmonic energy
What is the average NHR?
20 dB
Why do dysphonia voices have a low HNR?
Increased aperiodic or noisy components (e.g. roughness, breathiness, turbulent noise)
Assesses the interaction between the glottic source and the supraglottic (vocal tract) influences.
Spectral analysis
What are the 2 types of spectral analysis?
Spectrogram, line spectrum
Plots fo and Io in the time domain
Spectrogram
Plots all harmonic energies at a single point on the horizontal axis, with amplitude on the vertical axis
Line spectrum
A Fast Fourier Transform (FFT) analysis of the spectrum; an FFT of an FFT
Cepstral analysis
The dominant harmonic on the Cepstrum
Cepstral Peak Prominence (CPP)
The sharper the CPP, the stronger the ______ energy in the voice signal.
Periodic
Conversely, very “noisy” (e.g., breathy, rough) voices will have a _____ CPP.
Flat
