Cortical neurons make significant numbers of synaptic connections within one or two length constants of an axon
Figure 10. Reconstruction of the axonal projections of cortical neurons reveal that many of them make a large number of synaptic connections within the local network. These synapses may be modified by changes in the membrane potential of the presynaptic neuron. Each white point is the location of a putative synaptic bouton formed by that axon. On the right are a model of the distribution of axonal and synaptic connections for the cells on the left.