Attentional modulation of medial olivocochlear inhibition: evidence for immaturity in children.

Efferent feedback shapes afferent auditory processing. Auditory attention has been shown to modulate medial olivocochlear (MOC) efferent activity in human adults. Since auditory attention continues to develop throughout childhood, the present study explored whether attentional control of medial-efferent inhibition in 5-10 year-old children is adult-like. MOC inhibition was measured in adults (n = 14) and children (n = 12) during no-task (contralateral broadband noise), passive (contralateral noise with tone-pips) and active listening conditions (attended tone-pips embedded in contralateral broadband noise). A stronger MOC inhibition was observed when measured during the active listening condition for adults which is consistent with past work. However, the effect of auditory attention on MOC inhibition in children was not robust and was significantly lower compared to that observed for adults. These findings suggest the potential immaturity of the attentional mediation of MOC inhibition in tested children.