Ki. Mcanally et al., EFFECT OF TIME AND FREQUENCY MANIPULATION ON SYLLABLE PERCEPTION IN DEVELOPMENTAL DYSLEXICS, Journal of speech language and hearing research, 40(4), 1997, pp. 912-924
Many people with developmental dyslexia have difficulty perceiving sto
p consonant contrasts as effectively as other people and it has been s
uggested that this may be due to perceptual limitations of a temporal
nature. Accordingly, we predicted that perception of such stimuli by l
isteners with dyslexia might be improved by stretching hem in time-equ
ivalent to speaking slowly. Conversely, their perception of he some st
imuli ought to be made even worse by compressing them in time-equivale
nt to speaking quickly. We tested 15 children with dyslexia on their a
bility to identify correctly consonant-vowel-consonant (CVC) stimuli t
hat had been stretched or compressed in the time domain. We also teste
d their perception of he same CVC stimuli after the formant transition
s had been stretched or compressed in the frequency domain. Contrary t
o our predictions, we failed to Find any systematic improvement in hei
r performance with either manipulation. We conclude that simple manipu
lations in the time and frequency domains ore unlikely to benefit the
ability of people with dyslexia to discriminate between CVCs containin
g stop consonants.