Navigational strategies underlying phototaxis in larval zebrafish.
Navigational strategies underlying phototaxis in larval zebrafish.
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DOI：
10.3389/fnsys.2014.00039
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发表时间：
2014
影响因子：
3
通讯作者：
Engert F
中科院分区：
文献类型：
--
作者：
Chen X;Engert F
了解大脑如何将感官输入转化为复杂的行为是系统神经科学中的一个基本问题。利用斑马鱼幼体，我们研究了趋光性的时间分量，它被定义为基于连续时刻光强度比较的方向决策。我们开发了一种新颖的“虚拟圆”测定，其中当鱼游出虚拟限定的圆形边界时，全场照明突然关闭，并且当它返回到圆中时再次打开。动物没有接收到直接的空间线索，只经历全场的时间光变化。值得注意的是，鱼大部分时间都在无形的虚拟边界内度过。行为分析的游泳回合的光转换被用来开发四个离散的时间算法，将二进制的视觉输入（均匀的光/均匀的黑暗）到观察到的空间行为。在这些算法中，转向角度取决于紧接在各个转向事件之前的行为历史。计算机模拟表明，该算法重新获得了真实的鱼的大部分游泳统计信息。我们发现，在幼斑马鱼的转动性能明显调制的时间阶跃函数在光强度结合特定的运动历史之前，这些转折。行为的几个方面表明记忆使用多达10次游泳（约10秒）。因此，我们表明，一个复杂的行为，如空间导航，可以出现从少数相对简单的行为算法。
Understanding how the brain transforms sensory input into complex behavior is a fundamental question in systems neuroscience. Using larval zebrafish, we study the temporal component of phototaxis, which is defined as orientation decisions based on comparisons of light intensity at successive moments in time. We developed a novel “Virtual Circle” assay where whole-field illumination is abruptly turned off when the fish swims out of a virtually defined circular border, and turned on again when it returns into the circle. The animal receives no direct spatial cues and experiences only whole-field temporal light changes. Remarkably, the fish spends most of its time within the invisible virtual border. Behavioral analyses of swim bouts in relation to light transitions were used to develop four discrete temporal algorithms that transform the binary visual input (uniform light/uniform darkness) into the observed spatial behavior. In these algorithms, the turning angle is dependent on the behavioral history immediately preceding individual turning events. Computer simulations show that the algorithms recapture most of the swim statistics of real fish. We discovered that turning properties in larval zebrafish are distinctly modulated by temporal step functions in light intensity in combination with the specific motor history preceding these turns. Several aspects of the behavior suggest memory usage of up to 10 swim bouts (~10 sec). Thus, we show that a complex behavior like spatial navigation can emerge from a small number of relatively simple behavioral algorithms.