POWRE: Experimental Investigation of a Biological Ultrasonic Sensory System

最近，渔业生物学家在用超声波计算撞击发电厂进水口的鱼的数量时，偶然发现有几种鱼对频率在80到140千赫之间的脉冲声信号有反应。这种探测的机制尚不清楚，然而，这种鱼的内耳中的听泡，一种特殊的充满空气的结构，被认为起着主要作用。了解这种独特生物系统的机制有两个目的。首先，超声波信号检测的力学知识可以为开发新的和改进的生物医学应用换能器提供关键。其次，由于高功率的超声波信号被用来寻找和引导它们离开发电厂的进水口和水坝，这项研究的结果将提供关于什么声音更容易被clupeids检测到的信息，以及在不伤害它们内耳的情况下足以改变它们行为的声压级。本研究的目的是检查一种已知对超声波信号有行为反应的鱼的内耳力学，美洲鲥鱼（Alosa sapidissima）。该物种将通过测量膀胱、大泡膜和耳石对脉冲和连续波超声波的频率响应进行实验评估，使用非侵入性、非接触式振动测量系统，该系统已成功用于测量金鱼（carassiis auratus）和奥斯卡（Astronotus ocellatus）周围听觉器官的频率响应。本研究的结果将被用来建立一个数学模型，以动态响应的听觉系统的超声信号。这种模型是复制这种独特生物系统的特征用于生物医学工程应用的第一步。＊＊＊

9753091 Hastings Recently, fisheries biologists, using ultrasound to count the number of fish impinging on power plant intakes, serendipitously discovered that several species of clupeid fish respond to pulsed acoustic signals at frequencies from 80 to 140 kHz. The mechanism for such detection is not known, however, the auditory bullae, special air-filled structures in the inner ear of this family of fish are believed to play a major role. Understanding the mechanics of this unique biological system would serve two purposes. First, knowledge of the mechanics for detection of ultrasonic signals could provide the key to the development of new and improved transducers for biomedical applications. Second, since rather high power ultrasonic signals are being used both to find clupeids and to divert them from power plant intakes and dams, results of this research will provide information on what sounds would be more readily detected by clupeids and sound pressure levels that would be adequate to modify behavior without harming their inner ear. The objective of this study is to examine the mechanics of the inner ear of a clupeid fish known to respond behaviorally to ultrasonic signals, the American shad (Alosa sapidissima). This species will be experimentally evaluated by measuring the frequency response of the swimbladder, bullae membrane, and utricular otolith to both pulsed and continuous wave ultrasound using a noninvasive, noncontact vibration measurement system that has been used successfully to measure frequency responses of the peripheral auditory organs in the goldfish (Carassiiis auratus) and oscar (Astronotus ocellatus). Results of this study will be used to develop a mathematical model for the dynamic response of the clupeid auditory system to ultrasonic signals. Such a model is the first step in duplicating characteristics of this unique biological system for biomedical engineering applications. ***