Purpose The aims of the study were (a) to evaluate the effects of systematically varied factors of stimulus duration, interaural-level difference (ILD), and direction on perceptual and electrophysiological metrics of lateralization for fixed versus moving targets and (b) to evaluate the hemispheric activity underlying perception of fixed versus moving auditory targets. Method Twelve normal-hearing, young adult listeners were evaluated using perceptual and P300 tests of lateralization. Both perceptual and P300 tests utilized stimuli that varied for type (fixed and moving), direction (right and left), duration (100 and 500 ms), and magnitude of ILD (9 and 18 dB). Listeners provided laterality judgments and stimulus-type discrimination (fixed vs. moving) judgments for all combinations of acoustic factors. During P300 recordings, listeners discriminated between left- versus right-directed targets, as the other acoustic parameters were varied. Results ILD magnitude and stimulus type had statistically significant effects on laterality ratings, with larger magnitude ILDs and fixed type resulting in greater lateralization. Discriminability between fixed versus moving targets was dependent on stimulus duration and ILD magnitude. ILD magnitude was a significant predictor of P300 amplitude. There was a statistically significant inverse relationship between the perceived velocity of targets and P300 latency. Lateralized targets evoked contralateral hemispheric P300 activity. Moreover, a right-hemisphere enhancement was observed for fixed-type lateralized deviant stimuli. Conclusions Perceptual and P300 findings indicate that lateralization of auditory movement is highly dependent on temporal integration. Both the behavioral and physiological findings of this study suggest that moving auditory targets with ecologically valid velocities are processed by the central auditory nervous system within a window of temporal integration that is greater than that for fixed auditory targets. Furthermore, these findings lend support for a left hemispatial perceptual bias and right hemispheric dominance for spatial listening.

中文翻译：

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固定与移动声源偏侧化的感知和电生理相关性

目的该研究的目的是（a）评估刺激持续时间、耳间水平差异（ILD）和方向等系统不同因素对固定目标与移动目标侧化的知觉和电生理学指标的影响，以及（b）评估半球活动是固定与移动听觉目标感知的基础。 方法使用感知和 P300 偏侧化测试对 12 名听力正常的年轻成年听众进行了评估。知觉测试和 P300 测试均使用不同类型（固定和移动）、方向（左右）、持续时间（100 和 500 毫秒）以及 ILD 幅度（9 和 18 dB）的刺激。听众对所有声学因素的组合提供偏侧性判断和刺激类型辨别（固定与移动）判断。在 P300 录音期间，听众可以区分左向目标和右向目标，因为其他声学参数各不相同。 结果ILD 幅度和刺激类型对偏侧性评级具有统计显着影响，较大的 ILD 幅度和固定类型会导致更大的偏侧性。固定目标与移动目标之间的区分度取决于刺激持续时间和 ILD 强度。ILD 幅度是 P300 幅度的重要预测因子。目标感知速度与 P300 潜伏期之间存在统计学上显着的反比关系。偏侧目标诱发对侧半球 P300 活动。此外，对于固定类型的偏侧异常刺激，观察到右半球增强。 结论知觉和 P300 结果表明听觉运动的偏侧化高度依赖于时间整合。这项研究的行为和生理发现都表明，以生态上有效的速度移动的听觉目标是由中枢听觉神经系统在时间整合窗口内处理的，该时间整合窗口大于固定听觉目标的时间整合窗口。此外，这些发现支持左半球空间感知偏差和右半球在空间聆听方面的优势。