Causal impact of gamma phase on neural activity at other locations.

<p>(A) Principle of the calculation of TE quantifying the influence of phase at a “sending” recording site on the spiking activity at another “receiving” site. TE quantifies the information carried by the past values of the gamma phase at the sending site (the putative causal variable) about the current spiking activity at the receiving site (green arrow), while conditioning on the value of the past spiking activity at the receiving site (purple arrow). (B) TE values (Z-score units) averaged across all pairs of electrodes and sessions, during spontaneous activity and movie stimulation. Error bars indicate standard error (SE). Stars indicate significant increases during movie stimulation with respect to spontaneous activity (<i>t</i> test). (C) Spatial asymmetry ratio of TE values averaged across all couples of electrodes and sessions, during spontaneous activity and movie stimulation. Error bars indicate SE. (D) Histogram of TE values across all pairs of electrodes in all sessions, cropped to the 95th percentile. The electrode pairs were divided into four equipopulated ranges of interelectrode distances. (E) TE values (averaged across all pairs of electrodes in all sessions) quantifying the causal impact of phases of several frequency bands (whose frequency range is indicated in figure legend) during spontaneous activity and movie stimulation. Error bars indicate SE. Data available at <a href="http://dx.doi.org/10.6084/m9.figshare.1460872" target="_blank">http://dx.doi.org/10.6084/m9.figshare.1460872</a>.