A pilot study on the acoustic effects of a pseudo-palatal plate on speech: Implications for articulatory rehabilitation devices
Fig 6
Comparison results of the quadrilateral vowel space area (qVSA) before and after wearing the palatal plate.
The qVSA was calculated using the F1–F2 coordinates of the corner vowels/i/,/e/,/a/, and/u/. Blue and red shaded regions indicate the vowel space under normal (without plate) and wearing (with plate) conditions, respectively.