Interlaminar conduction. (A) SNR heatmaps at 1-ms intervals showing the spread of PV interneuron responses to stimulation in L2/3. (B) Latency versus distance within the stimulated column in the slice shown in A (R = 0.91, P = 0.005) yielded a conduction velocity of 360 μm/ms. (C) SNR heatmaps at 1-ms intervals showing PV interneuron responses to stimulation in L4. (D) Latency versus distance within the stimulated column in the slice shown in C (R = 0.78, P = 0.036) yielded a conduction velocity of 161 μm/ms. (E) SNR heatmaps at 0.5-ms intervals showing PV interneurons responses to stimulation in L5. (F) Latency versus distance within the stimulated column in the slice shown in E (R = 0.84, P = 8 × 10−6) yielded a conduction velocity of 412 μm/ms. In all SNR heatmaps, white stars mark stimulation site and solid white arrows show propagation trajectories used for velocity determination; dashed lines show layer boundaries, and dotted lines show column boundaries. Time after stimulation is shown in the upper right corner of each heatmap on yellow background.
