Backward masking in speech perception by children and adults

Abstract

The current investigation measured discrimination and identification of tone-noise and [b]-[a] stimuli by adults, children with normally developing language, and children with language impairment. The children were aged 4–6 years. These tasks were chosen instead of the more traditional two alternative forced choice (2AFC) technique because it was believed possible that task difficulty influenced previous results (e.g., Wright et al., 1997). The stimuli in the current set of experiments had longer tones (40 ms) than prior studies but used higher masker levels (52 dB spectrum level). However, results showed that all the participants discriminated the stimuli containing the tone or [b] signal significantly above chance, contrary to previous findings. More difficulty was found in the identification task, similar to prior backward masking results. [Supported by an Individual Development Award, NYS/UUP.]