In The Electric Synapse,
      . . . Ions move directly from one neuron to another by means of Gap Junctions.   Gap junctions are constructed of 12 copies of a single protein formed into a transmembrane channel that interconnects the cytoplasm of two adjacent neurons, allowing small molecules to pass between them.   The membrane depolarization associated with an Action Potential in the presynaptic cell passes through the gap junctions, leading to a depolarization and consequently the production of an action potential, in the postsynaptic cell.   When such an event occurs between neurons, they are said to be electrically coupled.

      Electric synapses have the advantage of speed; the direct transmission of impulses avoids the delay of about 0.5ms that is characteristic of chemical synapses.   Examples exist of electric coupling between groups of cell bodies and dendrites, ensuring simultaneous depolarization of entire groups of coupled cells.

      The efficiency with which an electric signal is transmitted across an electric synapse is proportional to the number of gap junctions that connect the cells.   The permeability of the gap junction is regulated by the level of cellular H⁺ ions and possibly of the Ca²⁺ ions;  changes in the concentration of these ions might modulate the efficiency of impulse transmissions at electric synapses.