Fig. 7: Examples of excitatory and inhibitory axons.
From: Tracing nerve fibers with volume electron microscopy to quantitatively analyze brain connectivity
a Tracings of axons (orange) from the stratum radiatum of the hippocampus (SR), and layers 1 and 3 of the somatosensory cortex (L1 and L3). Axons establish either excitatory synapses (green) or inhibitory synapses (red). Each axonal tracing is identified by the region (SR, L1 or L3), an identification number, and the linear density of synapses expressed as the number of synapses per micron. b Histograms of the distribution of the linear densities of synapses established by excitatory axons for each of the three regions.
