Abstract: The present study investigated the nature of the inhibitory syllable
frequency effect, recently reported for normal readers, in a German-speaking
dyslexic patient. The reading impairment was characterized as a severe deficit
in naming single letters or words in the presence of spared lexical processing
of visual word forms. Three visual lexical decision experiments were conducted
with the dyslexic patient, an unimpaired control person matched to the patient
and a control group: Experiment 1 manipulated the frequency of words and
word-initial syllables and demonstrated systematic effects of both factors in
normal readers and in the dyslexic patient. The syllable frequency effect was
replicated in a second experiment with a more strictly controlled stimulus set.
Experiment 3 confirmed the patient's deficit in activating phonological forms
from written words by demonstrating that a pseudohomophone effect as observed
in the unimpaired control participants was absent in the dyslexic patient.
Keywords: Acquired dyslexia, word frequency, syllable frequency, pseudohomophone effect, lexical decision, phonological processing of visual word forms
