Ponton Curtis, Eggermont Jos J, Khosla Deepak, Kwong Betty, Don Manuel
Electrophysiology Laboratory, House Ear Institute, 2100 West Third Street, Los Angeles, CA 90057, USA.
Clin Neurophysiol. 2002 Mar;113(3):407-20. doi: 10.1016/s1388-2457(01)00733-7.
Previous studies have shown that observed patterns of auditory evoked potential (AEP) maturation depend on the scalp location of the recording electrodes. Dipole source modeling incorporates the AEP information recorded at all electrode locations. This should provide a more robust description of auditory system maturation based on age-related changes in AEPs. Thus, the purpose of this study was to evaluate central auditory system maturation based dipole modeling of multi-electrode long-latency AEPs recordings.
AEPs were recorded at 30 scalp-electrode locations from 118 subjects between 5 and 20 years of age. Regional dipole source analysis, using symmetrically located sources, was used to generate a spatio-temporal source model of age-related changes in AEP latency and magnitude.
The regional dipole source model separated the AEPs into distinct groups depending on the orientation of the component dipoles. The sagittally oriented dipole sources contained two AEP peaks, comparable in latency to Pa and Pb of the middle latency response (MLR). Although some magnitude changes were noted, latencies of Pa and Pb showed no evidence of age-related change. The tangentially oriented sources contained activity comparable to P1, N1b, and P2. There were various age-related changes in the latency and magnitude of the AEPs represented in the tangential sources. The radially oriented sources contained activity comparable to the T-complex, including Ta, and Tb, that showed only small latency changes with age. In addition, a long-latency component labeled TP200 was observed.
It is possible to distinguish 3 maturation groups: one group reaching maturity at age 6 and comprising the MLR components Pa and Pb, P2, and the T-complex. A second group that was relatively fast to mature (50%/year) was represented by N2. A third group was characterized by a slower pattern of maturation with a rate of 11-17%/year and included the AEP peaks P1, N1b, and TP200. The observed latency differences combined with the differences in maturation rate indicate that P2 is not identical to TP200. The results also demonstrated the independence of the T-complex components, represented in the radial dipoles, from the P1, N1b, and P2 components, contained in the tangentially oriented dipole sources.
先前的研究表明，观察到的听觉诱发电位（AEP）成熟模式取决于记录电极的头皮位置。偶极子源建模整合了在所有电极位置记录的AEP信息。这应该能基于与年龄相关的AEP变化，对听觉系统成熟提供更可靠的描述。因此，本研究的目的是基于多电极长潜伏期AEP记录的偶极子建模来评估中枢听觉系统的成熟情况。
在118名5至20岁受试者的30个头皮电极位置记录AEP。使用对称定位的源进行区域偶极子源分析，以生成AEP潜伏期和波幅与年龄相关变化的时空源模型。
区域偶极子源模型根据成分偶极子的方向将AEP分为不同组。矢状方向的偶极子源包含两个AEP波峰，其潜伏期与中潜伏期反应（MLR）的Pa和Pb相当。尽管注意到了一些波幅变化，但Pa和Pb的潜伏期没有显示出与年龄相关变化的证据。切向方向的源包含与P1、N1b和P2相当的活动。切向源中所代表的AEP潜伏期和波幅存在各种与年龄相关的变化。径向方向的源包含与T复合波相当的活动，包括Ta和Tb，其随年龄仅显示出很小的潜伏期变化。此外，还观察到一个标记为TP200的长潜伏期成分。
可以区分出3个成熟组：一组在6岁时达到成熟，包括MLR成分Pa和Pb、P2以及T复合波。第二组成熟相对较快（每年50%），以N2为代表。第三组的特征是成熟模式较慢，速率为每年11 - 17%，包括AEP波峰P1、N1b和TP200。观察到的潜伏期差异与成熟速率差异表明P2与TP200不同。结果还证明了径向偶极子中所代表的T复合波成分与切向偶极子源中包含的P1、N1b和P2成分相互独立。
