Phase-difference-to-rate mapping.

<p>A) Joint probability density function of instantaneous phases of left and right primary motor cortex (M1). B) Same data as A, after change of variables to isolate the phase difference between left and right M1. Inter-hemispheric phase differences are statistically independent from local M1 phase. C) Example neuron sensitive to beta phase difference between left and right M1. During BC, lowest rate occurs near the most probable phase difference (peak of distribution in D), but the neuron increases spiking when the inter-hemispheric phase difference shifts to less probable values. Dots indicate measured rate, red line is best-fit von Mises type function (see <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002809#s2" target="_blank">Materials and Methods</a>). D) Distribution of inter-hemispheric phase differences (left M1 phase minus right M1 phase) during BC; empirical histogram estimate (black) and best-fit von Mises distribution (red). E) Same neuron as C, during MC. Despite only a small shift in the phase-difference distribution, the phase-difference-to-rate mapping has flipped for this cell. F) As in D, for MC.