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Using this ordered spreadsheet select the middle viable protrusion of the dendrite. If there are an even number of protrusions there will be 2. From the middle protrusion(s) count UP and DOWN the dendrite to include 7 more viable protrusions in each direction for a total of 15-16 initial sample synapses.
NOTE: For the purposes of this analysis a ‘viable’ protrusion is defined as a protrusion leading to a fully formed spine that includes an excitatory synapse. Therefore the protrusion stamps for shaft synapses, inhibitory spines, non-synaptic spines, and incomplete spines should be skipped. Multisynaptic and branched spines share protrusions, though all synapses will be included in the analysis so each synapse should be individually counted.
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