Fig. 8: Non-synaptic fibers.
From: Tracing nerve fibers with volume electron microscopy to quantitatively analyze brain connectivity
Fibers traversing the stacks of serial sections without establishing any synapses (purple) are represented in the stratum radiatum of the hippocampus (SR) and layers 1 and 3 of the somatosensory cortex (L1 and L3, respectively). The frontal faces of the stacks are oriented towards the observer; mesial is to the left, and lateral to the right. The top-down orientation of each stack is represented by the corresponding arrows (SLM stratum lacunosum-moleculare, SP stratum pyramidale). The fibers were traced from stacks of 305 (SR and L1) and 263 serial sections (L3). The samples show different densities of fibers (see also Table 1 and Fig. 9b). Fibers in the SR and L3 run in all directions, while the course of fibers in L3 seems to be mostly vertical.
