Sproule Michael K J, Chacron Maurice J
Department of Physiology, McGill University, Montreal, Québec, Canada.
PLoS One. 2017 Apr 6;12(4):e0175322. doi: 10.1371/journal.pone.0175322. eCollection 2017.
Neural heterogeneities are seen ubiquitously within the brain and greatly complicate classification efforts. Here we tested whether the responses of an anatomically well-characterized sensory neuron population to natural stimuli could be used for functional classification. To do so, we recorded from pyramidal cells within the electrosensory lateral line lobe (ELL) of the weakly electric fish Apteronotus leptorhynchus in response to natural electro-communication stimuli as these cells can be anatomically classified into six different types. We then used two independent methodologies to functionally classify responses: one relies of reducing the dimensionality of a feature space while the other directly compares the responses themselves. Both methodologies gave rise to qualitatively similar results: while ON and OFF-type cells could easily be distinguished from one another, ELL pyramidal neuron responses are actually distributed along a continuum rather than forming distinct clusters due to heterogeneities. We discuss the implications of our results for neural coding and highlight some potential advantages.
神经异质性在大脑中普遍存在，这使得分类工作变得极为复杂。在这里，我们测试了一个解剖学特征明确的感觉神经元群体对自然刺激的反应是否可用于功能分类。为此，我们记录了弱电鱼细吻无背电鳗的电感觉侧线叶（ELL）内锥体细胞对自然电通讯刺激的反应，因为这些细胞在解剖学上可分为六种不同类型。然后，我们使用两种独立的方法对反应进行功能分类：一种方法依赖于降低特征空间的维度，而另一种方法则直接比较反应本身。两种方法都产生了定性相似的结果：虽然ON型和OFF型细胞很容易相互区分，但由于异质性，ELL锥体细胞的反应实际上是沿着一个连续体分布的，而不是形成明显的簇。我们讨论了我们的结果对神经编码的影响，并强调了一些潜在的优势。
