Novelty Detection in Electric Fish

对于一种新的刺激，一般有三种行为反应：惊吓、唤醒和定向。惊吓反应是由短暂的刺激(通常是视觉或听觉刺激)引起的一组短潜伏期的肌肉收缩。惊吓阈值远远大于动物的检测阈值，这是其特点。唤醒行为的特征是一系列生理反应。虽然比惊吓行为更微妙，但有效的刺激和反应对于唤醒来说都是相当普遍的，这使得对参与新奇检测的单个神经元素的研究变得困难。虽然鱼类的定向反应尚未得到很好的定义，但脉冲型弱电鱼类的新奇反应最适合哺乳动物的这一类。这种新奇的反应是起搏器的瞬时加速，它驱动着鱼的电子器官。它是由检测阈值附近的微小刺激变化引起的，是一种微妙但可靠的行为，不具爆炸性，不应期短，涉及单一效应通路。脉冲式弱电鱼类的新奇反应非常适合神经生理学分析，并允许同时测量行为和神经反应。兰迪·泽里克博士将继续他在电鱼新颖性检测方面的工作。这项工作意义重大，因为它将使我们更好地理解神经系统区分小说和背景感官输入的方式。//

There are three general classes of behavioral responses to a novel stimulus: startle, arousal and orientation. The startle response is a short latency set of muscular contractions induced by a brief stimulus, typically visual or acoustic. It is characteristic for the startle threshold to be much greater than the animal's detection threshold. Arousal behavior is characterized by a suite of physical responses. Although more subtle than startle behavior, both the effective stimuli and the responses are quite general with arousal, making investigation of the individual neural elements involved in novelty detection problematic. Although orienting responses have not been well defined in fish, the novelty response of pulse-type weakly electric fish fits best into this category as defined for mammals. The novelty response is a transient acceleration of the pacemaker which drives the fish's electric organ. Elicited by small stimulus changes near detection threshold, it is a subtle but reliable behavior which is not explosive, has a short refractory period, and involves a single effector pathway. The novelty response of pulse-type weakly electric fish is well suited to neurophysiological analysis and permits simultaneous measurement of behavioral and neural responses. Dr. Randy Zelick will continue his work on novelty detection in electric fish. This work is significant since it will give us a better understanding of the means by which the nervous system distinguishes novel from background sensory input. //