From stimulus encoding to feature extraction in weakly electric fish
From stimulus encoding to feature extraction in weakly electric fish
复制标题
DOI：
10.1038/384564a0
复制
发表时间：
1996-12-12
期刊：
影响因子：
64.8
通讯作者：
Koch, C
中科院分区：
文献类型：
--
作者：
Gabbiani, F;Metzner, W;Koch, C
动物获取关于它们周围感觉刺激的信息，并使用模拟或基于脉冲的代码进行编码。需要从该表示中提取与行为相关的特征以进行进一步处理。在弱电鱼类的电感觉系统中，单个P型电感受器传入准确地编码了电场幅度随机调制的时间过程(1)。我们将一种刺激估计方法(2)和一种信号检测方法应用于P-受体传入及其靶点，即电感觉侧线叶中的锥体细胞。我们发现，尽管锥体细胞不能准确地传达有关刺激时间进程的详细信息，但它们可靠地编码电场幅度中随机调制的上下行程。这种时间特征的存在最好的信号是短时间的尖峰脉冲，这可能是由树突处理引起的，而不是由孤立的尖峰脉冲引起的。此外，锥体细胞在发出刺激波形中存在时间特征的信号方面优于P受体传入细胞。我们的结论是，感觉神经元专门用于准确地获取信息，只需很少的处理，而下一阶段提取与行为相关的特征，从而执行非线性模式识别任务。
ANIMALS acquire information about sensory stimuli around them and encode it using an analogue or a pulse-based code. Behaviourally relevant features need to be extracted from this representation for further processing. In the electrosensory system of weakly electric fish, single P-type electroreceptor afferents accurately encode the time course of random modulations in electric-field amplitude(1). We applied a stimulus estimation method(2) and a signal-detection method to both P-receptor afferents and their targets, the pyramidal cells in the electrosensory lateral-line lobe. We found that although pyramidal cells do not accurately convey detailed information about the time course of the stimulus, they reliably encode up- and downstrokes of random modulations in electric-field amplitude. The presence of such temporal features is best signalled by short bursts of spikes, probably caused by dendritic processing, rather than by isolated spikes. Furthermore, pyramidal cells outperform P-receptor afferents in signalling the presence of temporal features in the stimulus waveform. We conclude that the sensory neurons are specialized to acquire information accurately with little processing, whereas the following stage extracts behaviourally relevant features, thus performing a nonlinear pattern-recognition task.