Evidence of a speech evoked electrophysiological release from masking in noise

In this study, a release from masking (RFM) was sought with cortical auditory evoked potentials (CAEPs) elicited by speech (/da/) in competing continuous and interrupted noises. Two paradigms (i.e., fixed speech with varying signal-to-noise ratios and fixed noise with varying speech levels) were employed. Shorter latencies and larger amplitudes were observed in interrupted versus continuous noise at equivalent signal-to-noise ratios. With fixed speech presentation, P1-N1-P2 latencies were prolonged and peak N1 and P2 amplitudes decreased and more so with continuous noise. CAEP thresholds were lower in interrupted noise. This is the first demonstration of RFM with CAEPs to speech.