The thresholding to generate all-or-none action potentials gets way too much consideration. The real action is the flux of ionic currents across membranes. Action potential are easy to measure but important to remember that they are ONLY an intRAcellular form of communication. IntERcellular communication is via quantal and graded release and reuptake of transmitters that evoke graded ionic fluxes (with some exceptions). Brain is best viewed as massive analog computer with some facets of digital computing.
Retinal processing—the focus of this demonstration—is almost entirely computation by graded potentials, although some amacrine cells do spike.
Retinal processing—the focus of this demonstration—is almost entirely computation by graded potentials, although some amacrine cells do spike.