Table 4.
Distribution across the 11 coded distortion types and expressed as a proportion of all distortion errors in each participant group (282 for the nonfluent variant of primary progressive aphasia [nfvPPA], 139 for the logopenic variant of primary progressive aphasia [lvPPA]).
| Type of distortion errors coded | nfvPPA (%) | lvPPA (%) |
|---|---|---|
| Voicing ambiguity | 34.4 | 27.3 |
| Nasal ambiguity | 6.7 | 6.5 |
| Rhotic ambiguity | 2.5 | 1.4 |
| Frictionalized or weakened | 6.4 | 9.4 |
| Lengthened | 12.1 | 20.1 |
| Shortened | 1.8 | 3.6 |
| Centralized tongue body | 8.2 | 3.6 |
| Retracted tongue body | 6.7 | 5.8 |
| Advanced tongue body | 4.6 | 7.2 |
| Raised tongue body | 12.4 | 13.7 |
| Lowered tongue body | 4.3 | 1.4 |
Note. The distribution of distortions is presented within each speaker group and across all three speech samples.