Boothalingam Sriram, Allan Chris, Allen Prudence, Purcell David
National Center for Audiology, Western University, London, ON, Canada.
National Center for Audiology, Western University, London, ON, Canada; School of Communication Sciences and Disorders, Western University, London, ON, Canada.
PLoS One. 2015 Aug 28;10(8):e0136906. doi: 10.1371/journal.pone.0136906. eCollection 2015.
Behavioral manifestations of processing deficits associated with auditory processing disorder (APD) have been well documented. However, little is known about their anatomical underpinnings, especially cochlear processing. Cochlear delays, a proxy for cochlear tuning, measured using stimulus frequency otoacoustic emission (SFOAE) group delay, and the influence of the medial olivocochlear (MOC) system activation at the auditory periphery was studied in 23 children suspected with APD (sAPD) and 22 typically developing (TD) children. Results suggest that children suspected with APD have longer SFOAE group delays (possibly due to sharper cochlear tuning) and reduced MOC function compared to TD children. Other differences between the groups include correlation between MOC function and SFOAE delay in quiet in the TD group, and lack thereof in the sAPD group. MOC-mediated changes in SFOAE delay were in opposite directions between groups: increase in delay in TD vs. reduction in delay in the sAPD group. Longer SFOAE group delays in the sAPD group may lead to longer cochlear filter ringing, and potential increase in forward masking. These results indicate differences in cochlear and MOC function between sAPD and TD groups. Further studies are warranted to explore the possibility of cochlea as a potential site for processing deficits in APD.
与听觉处理障碍（APD）相关的处理缺陷的行为表现已有充分记录。然而，对于其解剖学基础，尤其是耳蜗处理，人们了解甚少。本研究在23名疑似患有APD（sAPD）的儿童和22名发育正常（TD）的儿童中，使用刺激频率耳声发射（SFOAE）群延迟测量耳蜗延迟（作为耳蜗调谐的指标），并研究听觉外周内侧橄榄耳蜗（MOC）系统激活的影响。结果表明，与TD儿童相比，疑似患有APD的儿童SFOAE群延迟更长（可能是由于耳蜗调谐更尖锐）且MOC功能降低。两组之间的其他差异包括TD组安静状态下MOC功能与SFOAE延迟之间存在相关性，而sAPD组则不存在。MOC介导的SFOAE延迟变化在两组之间方向相反：TD组延迟增加，而sAPD组延迟减少。sAPD组中较长的SFOAE群延迟可能导致耳蜗滤波器振荡时间延长，并可能增加前掩蔽。这些结果表明sAPD组和TD组在耳蜗和MOC功能方面存在差异。有必要进行进一步研究，以探索耳蜗作为APD处理缺陷潜在部位的可能性。
