Coding of spatial and temporal frequency in bat biosonar

蝙蝠生物声纳中空间和时间频率的编码

• 批准号: 254950776
• 负责人: Professor Dr. Lutz Wiegrebe (†)
• 金额: --
• 依托单位: Department Biologie II (aufgelöst)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/254950776?language=en
• 关键词: Coding; spatial; temporal; frequency; bat

The concept of spatial frequency, introduced in the pioneering work by Wiesel and Hubel into visual brain research, was instrumental in understanding how peripheral representations of objects are processed by the brain. Many studies have shown how well biosonar systems can replace or complement visual object perception but, despite a direct ecological relevance of spatial frequencies for echolocating bats, this parameter has not received any scientific attention in biosonar. Building upon psychophysical studies of bats hunting above water surfaces, both in the lab and in the field, we will test the hypothesis that bats can analyse both the spatial and temporal frequency patterns of natural water surfaces to identify disruptions thereof as possible prey. The experimental program starts out with two formal psychophysical detection experiments, quantifying perceptual sensitivity to spatial frequency and temporal frequency. On these foundations, masking along the spatial and temporal frequency axes will be investigated allowing for quantitative estimates of how-small prey-induced disruptions may be to be detectable by bats. These formal experiments are complemented with flight-room experiments where hunting sequences of biosonar specialists, Daubentons bats, are evaluated above a water surface where both spatial and temporal frequency of the water surface can be systematically manipulated. The proposed research will provide first insights into how a biosonar system solves these challenging tasks despite its lack of an explicit spatially arranged sensor array and its discontinuous temporal sampling.

威塞尔和休贝尔在视觉大脑研究的开创性工作中引入了空间频率的概念，它有助于理解大脑如何处理物体的外围表征。许多研究表明生物声纳系统可以很好地替代或补充视觉物体感知，但是尽管空间频率与回声定位蝙蝠具有直接的生态相关性，但该参数在生物声纳中尚未受到任何科学关注。基于实验室和野外对蝙蝠在水面上狩猎的心理物理学研究，我们将检验这样的假设：蝙蝠可以分析自然水面的空间和时间频率模式，以识别可能的猎物。该实验计划从两个正式的心理物理学检测实验开始，量化对空间频率和时间频率的感知敏感性。在此基础上，将研究沿空间和时间频率轴的掩蔽，从而定量估计蝙蝠可检测到的猎物引起的干扰有多小。这些正式实验与飞行室实验相辅相成，在飞行室实验中，生物声纳专家道本顿蝙蝠的狩猎序列在水面上方进行评估，可以系统地操纵水面的空间和时间频率。拟议的研究将首次深入了解生物声纳系统如何解决这些具有挑战性的任务，尽管它缺乏明确的空间排列传感器阵列和不连续的时间采样。