Electrical Spinal Imaging: A noninvasive, high-resolution approach that enables electrophysiological mapping of the human spinal cord
Fig 4
Latency distributions of the sP9 and sN13 waves.
Group-level data. Left column: sP9 (top) and sN13 (bottom) waves recorded from the top dorsal electrodes. Insets show the response over a larger time window; the box indicates the intervals around sP9 and sN13. Dots indicate the peak latency recorded from each electrode. The black dot and the horizontal black bar indicate the mean latency and latency range, respectively. Right column: Maps of the latency delays, with color-coding of time relative to the electrode with the shortest latency (highlighted in white, used as time 0). Note how, for the sP9 wave, the electrodes with shortest (whiter regions of spinal electrode topography, broadly corresponding to the C6-C7 segment) and longest latencies (redder regions) show a clear spatial gradient, indicating that the sP9 wave travels in the lateral-medial and caudal-rostral directions. Compare with the lack of any clear spatial gradient in the sN13. See also S3 Video. The data underlying this figure can be found at https://doi.org/10.17605/OSF.IO/KHJCG.