Perceptual learning of acoustic noise by individuals with dyslexia
Agus, T., Carrion Castillo, A., Pressnitzer, D., & Ramus, F.
Perceptual learning of acoustic noise by individuals with dyslexia. Journal of Speech, Language, and Hearing Research., 57
, 1069-1077. doi:10.1044/1092-4388(2013/13-0020).
Purpose: A phonological deficit is thought to affect most
individuals with developmental dyslexia. The present study
addresses whether the phonological deficit is caused by
difficulties with perceptual learning of fine acoustic details.
Method: A demanding test of nonverbal auditory memory,
“noise learning,” was administered to both adults with
dyslexia and control adult participants. On each trial, listeners
had to decide whether a stimulus was a 1-s noise token or
2 abutting presentations of the same 0.5-s noise token
(repeated noise). Without the listener’s knowledge, the exact
same noise tokens were presented over many trials. An
improved ability to perform the task for such “reference”
noises reflects learning of their acoustic details.
Results: Listeners with dyslexia did not differ from controls in
any aspect of the task, qualitatively or quantitatively. They
required the same amount of training to achieve discrimination
of repeated from nonrepeated noises, and they learned the
reference noises as often and as rapidly as the control group.
However, they did show all the hallmarks of dyslexia, including
a well-characterized phonological deficit.
Conclusion: The data did not support the hypothesis that
deficits in basic auditory processing or nonverbal learning and
memory are the cause of the phonological deficit in dyslexia