Department of Ophthalmology, Visual Processing Laboratory, Otto von Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany.
Eur J Neurosci. 2013 Aug;38(4):2557-65. doi: 10.1111/ejn.12264. Epub 2013 Jun 3.
Auditory evoked potentials (AEPs) to motion onset in humans are dominated by a fronto-central complex, with a change-negative deflection 1 (cN1) and a change-positive deflection 2 (cP2) component. Here the contribution of veridical motion detectors to motion-onset AEPs was investigated with the hypothesis that direction-specific adaptation effects would indicate the contribution of such motion detectors. AEPs were recorded from 33 electroencephalographic channels to the test stimulus, i.e. motion onset of horizontal virtual auditory motion (60° per s) from straight ahead to the left. AEPs were compared in two experiments for three conditions, which differed in their history prior to the motion-onset test stimulus: (i) without motion history (Baseline), (ii) with motion history in the same direction as the test stimulus (Adaptation Same), and (iii) a reference condition with auditory history. For Experiment 1, condition (iii) comprised motion in the opposite direction (Adaptation Opposite). For Experiment 2, a noise in the absence of coherent motion (Matched Noise) was used as the reference condition. In Experiment 1, the amplitude difference cP2 - cN1 obtained for Adaptation Same was significantly smaller than for Baseline and Adaptation Opposite. In Experiment 2, it was significantly smaller than for Matched Noise. Adaptation effects were absent for cN1 and cP2 latencies. These findings demonstrate direction-specific adaptation of the motion-onset AEP. This suggests that veridical auditory motion detectors contribute to the motion-onset AEP.
听觉事件相关电位（AEPs）对人类运动起始的反应主要集中在前额和中央区域，表现为一个负向偏转 1（cN1）和一个正向偏转 2（cP2）的复合波。本研究旨在通过假设方向特异性适应效应能够指示这种运动探测器的作用，来探讨真实运动探测器对运动起始 AEPs 的贡献。通过 33 个脑电图通道记录了测试刺激（即水平虚拟听觉运动的起始，每秒 60°）从正前方到左侧的运动起始 AEPs。在两个实验中，比较了三种条件下的 AEPs，它们在运动起始测试刺激之前的历史记录有所不同：（i）无运动历史（基线），（ii）与测试刺激方向相同的运动历史（适应相同），（iii）听觉历史的参考条件。在实验 1 中，条件（iii）包括相反方向的运动（适应相反）。在实验 2 中，使用无相干运动的噪声（匹配噪声）作为参考条件。在实验 1 中，适应相同条件下获得的 cP2-cN1 振幅差明显小于基线和适应相反条件。在实验 2 中，它明显小于匹配噪声条件。cN1 和 cP2 潜伏期没有适应效应。这些发现表明运动起始 AEP 具有方向特异性适应。这表明真实的听觉运动探测器对运动起始 AEP 有贡献。
