Abstract:

Aspects of auditory processing related to temporal and spectral resolution were investigated in 50 adult subjects (aged 18-58) with varying reading abilities. The tests administered included tone detection, tone frequency discrimination, tone sequencing, interval discrimination, and gap detection. Tones were either long (250 ms) or short (20 ms) and ranged in frequency between 600 and 1400 Hz. Detection and frequency discrimination tasks were given in the clean and in a masking context, in which tones were followed by 300-ms bandpass noise. Thresholds were determined using an adaptive procedure. Backward masking interferences for short tones, as well as interval and frequency discrimination limens were substantially elevated for most poor readers, and were correlated with one another. Three-tone sequencing and short-tone frequency discrimination in a masking context were especially strongly correlated with single-word reading ability. Gap detection thresholds did not correlate with other tasks or with reading ability. In sum, spectral-temporal auditory processing resolution appears to be related to reading ability, possibly via an acoustically based deficit in phonetic development. These findings raise the question of whether nonspeech acoustic training can be used to improve adults' reading ability. [Work supported by Scientific Learning Corporation.]