A dedicated neural mechanism for vowel selection: a case of relative vowel deficit sparing the number lexicon.
We report the case of an Italian speaker (GBC), with classical Wernicke's aphasia following a vascular lesion in the posterior middle temporal region. GBC exhibited a selective deficit in spoken language production affecting vowels more than consonants. In reading from a newspaper, GBC substituted vowels for other vowels from the Italian inventory at a rate of 7/1 compared to consonants. No effects of frequency or grammatical class were found. Vowel errors could also not be accounted for by morphological or known phonological processes. Production of number words, in contrast, was free from phonological errors. While GBC has intact representations of Italian vowels and consonants, his data argue for a separate selection mechanism for vowels that is dissociable from that used for consonants. This case provides neuropsychological evidence for models of word production that distinguish between the abstract phonological properties of a word (e.g., sequencing of phonemic slots, or "CV skeleton") and a separate representation for the specific sounds (melody).
Semenza
Carlo
C
University of Trieste, Italy.
Bencini
Giulia M L
GM
Bertella
Laura
L
Mori
Ileana
I
Pignatti
Riccardo
R
Ceriani
Francesca
F
Cherrick
Danielle
D
Caldognetto
Emanuela Magno
EM
D001041:Aphasia, Wernicke / Q000473:pathology / Q000523:psychology*; D003657:Decision Making / Q000502:physiology; D004192:Discrimination, Psychological; D006801:Humans; D002546:Ischemic Attack, Transient / Q000473:pathology / Q000523:psychology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011578:Psycholinguistics; D011597:Psychomotor Performance / Q000502:physiology; D011932:Reading; D013060:Speech; D013702:Temporal Lobe / Q000473:pathology