Distortion type	Definition
1. Voicing ambiguity	Voiced consonants are partially devoiced, or voiceless consonants are partially voiced.
2. Nasal ambiguity	Nasal sounds are partially denasalized, nonnasal sounds are nasalized, or there is audible nasal emission.
3. Rhotic ambiguity	Partially rhotacized (r-colored) nonrhotic sounds or partially derhotacized rhotic sounds.
4. Frictionalized/weakened	Stops produced as a fricative-like sound or weakened constriction of any consonant.
5. Lengthened	Unequivocal and considerable lengthening given current speaking rate.
6. Shortened	Unequivocal and considerable shortening given current speaking rate.
7. Centralized tongue body	The tongue has shifted toward the center of the oral cavity.
8. Retracted tongue body	The tongue has shifted backward in the oral cavity.
9. Advanced tongue body	The tongue has shifted forward in the oral cavity.
10. Raised tongue body	The tongue has shifted higher in the oral cavity.
11. Lowered tongue body	The tongue has shifted lower in the oral cavity.