Figure 4B to 4F show the t-sne results arising from the same dataset with some electrodes removed. From B to F the number of electrodes used were 64, 32, 22, 16, and 8 respectively (denoted as blue in the figure). The color coding in these subplots is the same as in Figure 4a and denotes the unit each spike belongs to as defined by the above procedure. Even at 64 channels there is an obvious deterioration of the t-sne clustering quality that progresses all the way to the 8 channel data set. This deterioration can be seen as a reduction of the number of easy to delineate spike groups, an increase of the number of spikes that form part of the larger amorphous clouds, and by the mixing of the labeled spikes amongst the unit clusters and between the clusters and the undifferentiated cloud structures.