What are on center and off-center cells?

What are on center and off-center cells?

The major functional subdivision of ganglion cells in the mammalian retina is into ON- and OFF-center ganglion cells. ON-center cells are depolarized by illumination of their receptive field center (RFC), while OFF-center cells are depolarized by decreased illumination of their RFC.

What activates an on center ganglion cell?

When a receptor cell is activated by light, the bipolar cell directly in line with it is also activated. The bipolar cell in turn activates its corresponding ganglion cell.

What is an off-center on surround cell?

An OFF-center/ON-surround ganglion cell has the opposite arrangement. It gets inhibition from a small spot of light in the center, and excitation from an annulus in the surround.

What is an on center cell?

They are called ON-centre cells and OFF-centre cells. If a light stimulus applied to the centre of a bipolar cells’s receptive field has an excitatory effect on that cell, causing it to become depolarized, it is an ON-centre cell.

What are off-center and on-center bipolar cells of eye and what are their functions?

There are two types of bipolar cells, both of which receive the glutamate neurotransmitter, but the ON-center bipolar cells will depolarize, whereas the OFF-center bipolar cells will hyperpolarize. This arrangement helps provide a spatial processing of the visual input derived from the photoreceptor cells.

What are on and off pathways?

Visual processing is largely organized into ON and OFF pathways that signal stimulus increments and decrements, respectively. These pathways exhibit natural pairings based on morphological and physiological similarities, such as ON and OFF α-ganglion cells in the mammalian retina.

What do ganglion cells do in the eye?

Retinal ganglion cells process visual information that begins as light entering the eye and transmit it to the brain via their axons, which are long fibers that make up the optic nerve. There are over a million retinal ganglion cells in the human retina, and they allow you to see as they send the image to your brain.

WHAT ARE ON and OFF bipolar cells?

ON-center bipolar cells are depolarized by small spot stimuli positioned in the receptive field center. OFF-center bipolar cells are hyperpolarized by the same stimuli. Both types are repolarized by light stimulation of the peripheral receptive field outside the center (Fig. 1).