Figure 3.

Set of 3 representative FESEM images of 70 nm sections from series of 25 on carbon coated glass coverslip. Arrows (a, b) and asterisks (c) mark two different synaptic contacts onto a dually innervated spine. Panel d shows a 3D reconstruction of the dual innervations and accompanying synaptic vesicles in red and blue. Scale bar, 200 nm. Animal use in this experiment was conducted in strict accordance to our institutional animal care and use committee guidelines.