“Conductance” By Christoph Straub, Sabatini Lab, Harvard Medical School. Interstellate Volume 1.
When an excitatory signal is received at the dendrites of a neuron, the membrane of the neuron becomes depolarized, or more positively charged than its surrounding environment. When the neuron become sufficiently depolarized, it fires an action potential, which is a brief electrical impulse that travels away from the cell body, down the axon, and causes neurotransmitter to be released. These hippocampal neurons are labeled with soluble tdTomato.