Cochlear measures of selective auditory attention. Free

The possibility that selective auditory attention can affect the responses of the cochlea via the medial olivocochlear (MOC) pathway was investigated in human listeners using a nonlinear version of the stimulus‐frequency otoacoustic emission (SFOAE), called the nSFOAE [Walsh et al. (2010)]. During nSFOAE recording, listeners attended to one of two competing speech streams, each composed of seven randomly‐selected spoken digits that were interleaved with the nSFOAE stimuli. The talker was female in one ear and male in the other (randomized across trials). The task of the listener was to match a subset of the digits spoken by the female talker to one of two choices presented visually on a computer screen. The nSFOAE stimulus was a tone (4.0 kHz, 200 ms) presented simultaneously to the two ears, either in quiet (tone‐alone) or in noise (tone‐plus‐noise). When nSFOAEs were measured during periods of selective attention, the tone‐plus‐noise responses exhibited larger maximum magnitudes, and larger changes from the tone‐alone magnitudes, compared to the responses measured during a no‐attention condition, in which the competing speech streams were presented, but with no digit‐matching required. The differences in magnitudes across conditions were as much as 4–5 dB. [Work supported by the NIDCD.]