FIGURE 4. Schematic diagram illustrating the organization of cortical connections proposed in this study.
From the following article:
Excitatory cortical neurons form fine-scale functional networks
Yumiko Yoshimura, Jami L. M. Dantzker and Edward M. Callaway
Nature 433, 868-873(24 February 2005)
doi:10.1038/nature03252
Excitatory connections from layer 4 to layer 2/3 and within layer 2/3 define groups of selectively interconnected neurons (red or blue). The organization of excitation from layer 5 (grey triangles) and inhibition from layers 2/3 and 4 interneurons (IN, grey ovals) does not respect the fine-scale interconnected cell groups defined by excitatory connections from layer 4 and within layer 2/3.