I believe I just found a synapse.
Thanks for the extra information! It’s great to be able to learn about this while actually seeing it when tracing.
@whathecode The illustration that you posted is probably intended for the cerebral cortex. Synapses between cortical pyramidal neurons are usually made onto dendritic spines, which is a classic fact found in most textbooks. I’m not sure how many retinal synapses are made onto spines…we’d have to ask an expert or read some papers to find out. I found this old paper by searching on Google Scholar, and I’m sure there are more. http://www.ncbi.nlm.nih.gov/pubmed/12106402 In any case, you’re right, this is a candidate for a synapse.