Action Enhances Acoustic Cues for 3-D Target Localization by Echolocating Bats

Under natural conditions, animals encounter a barrage of sensory information from which they must select and interpret biologically relevant signals. Active sensing can facilitate this process by engaging motor systems in the sampling of sensory information. The echolocating bat serves as an excellent model to investigate the coupling between action and sensing because it adaptively controls both the acoustic signals used to probe the environment and movements to receive echoes at the auditory periphery. We report here that the echolocating bat controls the features of its sonar vocalizations in tandem with the positioning of the outer ears to maximize acoustic cues for target detection and localization. The bat’s adaptive control of sonar vocalizations and ear positioning occurs on a millisecond timescale to capture spatial information from arriving echoes, as well as on a longer timescale to track target movement. Our results demonstrate that purposeful control over sonar sound production and reception can serve to improve acoustic cues for localization tasks. This finding also highlights the general importance of movement to sensory processing across animal species. Finally, our discoveries point to important parallels between spatial perception by echolocation and vision.

在自然环境中，动物会接收到海量感官信息，必须从中筛选并解读具备生物学意义的信号。主动感知（active sensing）可通过调动运动系统参与感官信息采样，推进这一信息处理流程。回声定位蝙蝠（echolocating bat）是研究动作与感知耦合机制的绝佳模型：这类动物可自适应调控用于探测环境的声学信号，以及接收听觉外周回声的肢体运动。本研究发现，回声定位蝙蝠会协同调控其声呐发声特征与外耳位置，以最大化用于目标探测与定位的声学线索。蝙蝠对声呐发声与外耳位置的自适应调控，既会以毫秒级时间尺度捕捉抵达回声中的空间信息，也会在更长时间尺度上追踪目标的运动状态。本研究结果证实，对声呐发声与接收的有意识调控，可优化定位任务所需的声学线索。该发现同时凸显了运动对跨物种感官处理过程的普遍重要性。最后，本研究的发现还揭示了回声定位空间感知与视觉空间感知之间存在的重要相似性。