Symmetric biphasic patterned stimulation of retinal ganglion cells

Vision is the complex information processing which relies on the neural processing of the retina. Light incident on the tissue layer of retina which is sensible to light, produces a series of electrical and chemical synapses which creates the nerve impulses. The light passing the pupil gets focused by the lens presents an inverted image to the photoreceptors called the rods and cones. Neural signals from the rods and cones are processed in the retinal ganglion cells (RGC) whose axons form the optic nerve. These nervous messages are mostly associated with an electrical change known as the action potential. An all active Fohlmeister – Coleman – Miller (FCM) model with five nonlinear ion channels is modelled for the RGC, with an intracellular resistance (Ra), a membrane mechanism in parallel with a membrane capacitance and also a gap junction conductance (G) in between the compartments. The simulations were done for the above mentioned FCM neuron model and are analysed by stimulating with a constant dc current and also with a patterned biphase current stimulation with Inter Phase Gap (IPG). The action potential of the designed RGCs and the electrotonic current flowing across the boundaries were figured out for different patterned stimulating current and gap junction conductances.