Fig. 2.

Cluster analysis-based physiological classification of pyramidal neurons in monkey DLPFC. A: the dendrogram obtained through Ward's hierarchical clustering algorithm revealed 4 clusters, demonstrating the presence of distinct physiological groups of pyramidal neurons. RS_LRi, RS cells with low input resistance; RS_HRi, RS cells with high input resistance. B: the number of neurons of each subjectively characterized electrophysiological type in the 4 clusters obtained with Ward's clustering method. Clusters 1 and 2 included mostly RS cells, cluster 3 included IM and RS cells, and cluster 4 consisted of LTS cells.