Dichotomy of Action-Potential Backpropagation in CA1 Pyramidal Neuron Dendrites

1 Department of Neurobiology and Physiology, Institute for Neuroscience and 2 Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, Illinois 60208 Golding, Nace L., William L. Kath, and Nelson Spruston. Dichotomy of Action-Potential Backpropagation in CA1 Pyramidal Neuron Dendrites. J. Neurophysiol. 86: 2998-3010, 2001. In hippocampal CA1 pyramidal neurons, action potentials are typically initiated in the axon and backpropagate into the dendrites, shaping the integration of synaptic activity and influencing the induction of synaptic plasticity. Despite previous reports describing action-potential propagation in the proximal apical dendrites, the extent to which action potentials invade the distal dendrites of CA1 pyramidal neurons remains controversial. Using paired somatic and dendritic whole cell recordings, we find that in the dendrites proximal to 280 µm from the soma, single backpropagating action potentials exhibit