We report our investigations of a case of refractory anemia. FAS developed
a non-fluent aphasia with relative sparing of his single-word production an
d comprehension abilities. Neuropsychological and SPECT investigations were
consistent with a focal dysfunction of the left frontal regions. Although
FAS was able to retrieve many single words, he was very variable. Blocks of
repeated naming trials were administered in which sets of six targets were
named three times in a random order. FAS performed more successfully on bl
ocks of semantically unrelated items than on blocks of semantic co-ordinate
s. Items at the start of a trial block were more likely to be retrieved suc
cessfully. A rest interval of 10 s between the production of a response and
initiation of the following trial led to significantly improved performanc
e. FAS was able to read these same words under speeded conditions without a
ny impairment. These findings are discussed in the light of evidence for re
fractoriness within semantic access procedures and in the context of curren
t models of language production. It is argued that FAS has a prolongation o
f the normal inhibitory processes that are implicated at post-semantic and
pre-phonological levels of speech production.