Cortical pyramidal neurons form tens of thousands of synaptic connections across their intricately branched dendritic trees. My research integrates neuronal morphology analysis with biophysical modeling to investigate dendritic integration and neuronal coding within neuronal circuits. I utilize 3D nanoscale reconstructions of neurons from serial electron microscopy, with a particular focus on dendritic spine morphologies and their distribution along the dendritic tree. Our findings reveal a correlation between spine neck shape and electrical resistance, demonstrating how these structural properties influence signal amplitude and timing. Deciphering these principles is essential for advancing our understanding of brain function in both health and disease.