Victor J D, Purpura K P
Department of Neurology and Neuroscience, Cornell University Medical College, New York, New York 10021, USA.
Ann N Y Acad Sci. 1997 Dec 19;835:330-52. doi: 10.1111/j.1749-6632.1997.tb48640.x.
We described a novel approach to the study of how spike trains encode sensory information. This approach emphasizes the idea that spike trains are sequences of discrete events, rather than approximations to continuous signals. Aided by some simple heuristics, such as a caricature of neurons as coincidence detectors, we constructed candidate notions of "distances" between spike trains, considered as points in an abstract space. Each candidate distance was evaluated for relevance to biological encoding by determining whether it led to systematic, stimulus-dependent, clustering of the neural responses. We showed here that these distance can also be used to construct a "response space" for the neuron. The response space, which is typically not Euclidean, can represent two or three stimulus attributes. We also introduced the notion of a "consensus spike train," defined as the spike train with minimum average distance from a set of observed responses. For the distances we considered, the consensus spike train (for a particular stimulus) contained only those spikes that were present at consistent times across the observed responses to that stimulus, and thus contained fewer spikes than the typical observed responses. Nevertheless, these consensus spike trains provided an equivalent (or even superior) representation of the stimulus array.
我们描述了一种研究尖峰序列如何编码感官信息的新方法。这种方法强调尖峰序列是离散事件的序列，而不是连续信号的近似值。借助一些简单的启发式方法，比如将神经元 caricature 为巧合探测器，我们构建了尖峰序列之间“距离”的候选概念，将其视为抽象空间中的点。通过确定每个候选距离是否导致神经反应的系统的、依赖刺激的聚类，来评估其与生物编码的相关性。我们在此表明，这些距离还可用于构建神经元的“反应空间”。反应空间通常不是欧几里得空间，可表示两个或三个刺激属性。我们还引入了“共识尖峰序列”的概念，定义为与一组观察到的反应平均距离最小的尖峰序列。对于我们考虑的距离，（针对特定刺激的）共识尖峰序列仅包含在对该刺激的观察反应中一致时间出现的那些尖峰，因此包含的尖峰比典型的观察反应少。然而，这些共识尖峰序列提供了刺激阵列的等效（甚至更好）表示。
