The olivocochlear reflex may unmask speech from noise via dynamic-range restoration

Evidence

A more widely accepted role is that the MOCR possibly facilitates understanding speech in noisy environments. This idea is based on the fact that MOC efferent activation restores the dynamic range of auditory nerve fibre responses in noisy backgrounds to values observed in quiet (Fig. 5 in Guinan 2006 ), something that probably improves the neural coding of speech embedded in noise (Brown et al. 2010 ; Chintanpalli et al. 2012 ; Clark et al. 2012 ). The evidence in support for this unmasking role of the MOCR during natural listening is, however, still indirect (Kim et al. 2006 ). A direct demonstration would require being able to selectively deactivate the MOCR while keeping afferent auditory nerve fibres functional. — Dijk, Pim van, Physiology, Psychoacoustics and…, 1940

Categorization

• QUESTION: The unmasking role remains only indirectly evidenced — worth tracking whether later work confirms it directly.