Dorman Michael F, Sharma Anu, Gilley Phillip, Martin Kathryn, Roland Peter
Department of Speech and Hearing Science, Arizona State University, AZ, USA.
J Commun Disord. 2007 Jul-Aug;40(4):284-94. doi: 10.1016/j.jcomdis.2007.03.007. Epub 2007 Mar 14.
In normal-hearing children the latency of the P1 component of the cortical evoked response to sound varies as a function of age and, thus, can be used as a biomarker for maturation of central auditory pathways. We assessed P1 latency in 245 congenitally deaf children fit with cochlear implants following various periods of auditory deprivation. If children experience less than 3.5 years of auditory deprivation before implantation, P1 latencies fall into the range of normal following 3-6 months of electrical stimulation. Children who experience greater than 7 years of deprivation, however, generally do not develop normal P1 latencies even after years of stimulation. Moreover, the waveforms for these patients can be markedly abnormal. Cortical reorganization stimulated by deprivation is likely to be a significant factor in both variation in the latency and morphology of the cortical evoked response to sound for children fit with a cochlear implant and variation in the development of oral speech and language function.
The reader will be introduced to research using cortical evoked responses (CAEPs), positron emission tomography (PET) scans and in-depth recording from the auditory cortex of congenitally deaf cats that converges on the existence of a sensitive period for the development of central auditory pathways in children. The reader will also be provided with two case studies that illustrate the use of the P1 response as biomarker for development of central auditory pathways. Finally, suggestions for future research will be provided.
在听力正常的儿童中，皮层听觉诱发电位P1成分的潜伏期随年龄而变化，因此可作为中枢听觉通路成熟的生物标志物。我们评估了245名先天性耳聋儿童在接受不同时期听觉剥夺后植入人工耳蜗后的P1潜伏期。如果儿童在植入前经历的听觉剥夺少于3.5年，在电刺激3 - 6个月后，P1潜伏期会落入正常范围。然而，经历超过7年听觉剥夺的儿童，即使经过多年刺激，通常也不会形成正常的P1潜伏期。此外，这些患者的波形可能明显异常。剥夺所引发的皮层重组可能是影响人工耳蜗植入儿童对声音的皮层诱发电位潜伏期和形态变化以及口语和语言功能发展变化的一个重要因素。
读者将了解到利用皮层听觉诱发电位（CAEP）、正电子发射断层扫描（PET）以及对先天性耳聋猫听觉皮层进行深入记录的研究，这些研究都指向儿童中枢听觉通路发育存在一个敏感期。读者还将看到两个案例研究，展示了如何将P1反应用作中枢听觉通路发育的生物标志物。最后，将提供未来研究的建议。
