Delayed detection of tonal targets in background noise in dyslexia

Brain Lang. 2007 Jul;102(1):80-90. doi: 10.1016/j.bandl.2006.07.001. Epub 2006 Aug 2.

Abstract

Individuals with developmental dyslexia are often impaired in their ability to process certain linguistic and even basic non-linguistic auditory signals. Recent investigations report conflicting findings regarding impaired low-level binaural detection mechanisms associated with dyslexia. Binaural impairment has been hypothesized to stem from a general low-level processing disorder for temporally fine sensory stimuli. Here we use a new behavioral paradigm to address this issue. We compared the response times of dyslexic listeners and their matched controls in a tone-in-noise detection task. The tonal signals were either Huggins Pitch (HP), a stimulus requiring binaural processing to elicit a pitch percept, or a pure tone-perceptually similar but physically very different signals. The results showed no difference between the two groups specific to the processing of HP and thus no evidence for a binaural impairment in dyslexia. However, dyslexic subjects exhibited a general difficulty in extracting tonal objects from background noise, manifested by a globally delayed detection speed.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acoustic Stimulation
  • Adult
  • Auditory Perceptual Disorders / complications
  • Auditory Perceptual Disorders / physiopathology*
  • Dyslexia / complications
  • Dyslexia / physiopathology*
  • Female
  • Humans
  • Male
  • Noise
  • Pitch Discrimination / physiology*