Dataset for: Interaction of Spatial and Non-Spatial Cues in Auditory Stream Segregation in the European Starling

Integrating sounds from the same source and segregating sounds from different sources in an acoustic scene is an essential function of the auditory system. Naturally, the auditory system simultaneously makes use of multiple cues. Here, we investigate the interaction between spatial cues and frequency cues in stream segregation of European starlings (Sturnus vulgaris) using an objective measure of perception. Neural responses to streaming sounds were recorded while the bird was performing a behavioral task that results in a higher sensitivity during a one-stream than a two-stream percept. Birds were trained to detect an onset time shift of a B tone in an ABA- triplet sequence in which A and B could differ in frequency and/or spatial location. If the frequency difference or spatial separation between the signal sources or both were increased, the behavioral time shift detection performance deteriorated. Spatial separation had a smaller effect on the performance compared to the frequency difference and both cues additively affected the performance. Neural responses in the primary auditory forebrain were affected by the frequency and spatial cues. However, frequency and spatial cue differences being sufficiently large to elicit behavioral effects did not reveal correlated neural response differences. The difference between the neuronal response pattern and behavioral response is discussed with relation to the task given to the bird. Perceptual effects of combining different cues in auditory scene analysis indicate that these cues are analyzed independently and given different weights suggesting that the streaming percept arises consecutively to initial cue analysis.

在声学场景中整合同源声音并分离异源声音，是听觉系统的一项核心功能。听觉系统自然会同时利用多种线索（cue）。本研究通过客观知觉测量方法，探究欧洲椋鸟（Sturnus vulgaris）听觉流分离（stream segregation）任务中空间线索与频率线索的交互作用。研究记录了鸟类执行某项行为任务时，对听觉流声音的神经响应；该任务下，单流知觉（one-stream percept）状态下的敏感性高于双流知觉（two-stream percept）状态。实验训练鸟类检测ABA三联序列中B音的起始时移（onset time shift），该序列中A与B的频率和/或空间位置可存在差异。若信号源间的频率差或空间间距增大，或两者同时增大，则行为层面的时移检测性能会出现下降。相较于频率差，空间间距对任务性能的影响更小，且两类线索会以相加方式共同影响任务表现。初级听觉前脑（primary auditory forebrain）的神经响应会受到频率与空间线索的调控。然而，即便频率与空间线索的差异大到足以引发行为层面的效应，也未观察到与之对应的神经响应差异。研究结合鸟类所执行的任务，探讨了神经元响应模式与行为响应之间的差异。在听觉场景分析中，整合不同线索所产生的知觉效应表明，这些线索会被独立分析并赋予不同权重，这提示流知觉是在初始线索分析之后依次产生的。