Figure 3. Representative electron micrographs of subtypes of layer V motor cortical axodendritic synapses.
Synapses with perforated or segmented post-synaptic densities were identified as perforated (Perf) synapses. Boutons forming synaptic contacts with more than one distinct dendritic element (spine or shaft) were identified as multisynaptic boutons (MSBs). These synapse subtypes were chosen for analysis because they have been linked to increased synaptic efficacy.