POWRE: Experimental Investigation of a Biological Ultrasonic Sensory System

9753091黑斯廷斯最近，渔业生物学家使用超声波来计算撞击发电厂进水口的鱼的数量，偶然发现几种杆状鱼类对频率从80到140千赫的脉冲声波信号做出反应。这种探测的机制尚不清楚，然而，听觉大泡，即这种鱼类内耳中特殊的充气结构，被认为发挥了主要作用。了解这一独特生物系统的机制有两个目的。首先，超声信号检测机制的知识可以为开发用于生物医学应用的新的和改进的换能器提供关键。其次，由于相当高功率的超声波信号既被用来寻找棍虫，又被用来将它们从发电厂进水口和大坝转移，这项研究的结果将提供关于棍虫更容易检测到什么声音的信息，以及足以在不损害内耳的情况下改变行为的声压级。这项研究的目的是研究一种已知的对超声波信号做出行为反应的团头鱼的内耳的机制。该物种将通过使用非侵入性、非接触式振动测量系统测量游泳、水泡膜和椭圆形耳石对脉冲和连续波超声波的频率响应来进行实验评估，该系统已成功地用于测量金鱼(Carassiiis Auratus)和奥斯卡(Astronotus Ocellatus)周围听觉器官的频率响应。这项研究的结果将被用来建立棒状听觉系统对超声信号的动态响应的数学模型。这样的模型是为生物医学工程应用复制这一独特生物系统的特征的第一步。***

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. ***