The lens in turn focuses the light rays onto the retina, lining the back of the eye. The retina converts the image formed by the light rays into nerve impulses. The optic nerve, composed of the axons of the retina's ganglion cells, then transmits these impulses from the eye to the first visual relay in the brain.

Obviously, optic nerve takes visual information
gathered from your eye and transmits it using a series of electrical impulses to the parts of your brain that act as vision centers, allowing you to make sense of what you are seeing...

Electric nerve impulses from the retina to the brain are conveyed by the optic nerves.

The optic nerves play a crucial role in transmitting visual information from the retina to the brain. These nerves are responsible for carrying electrical signals, known as nerve impulses, which contain information about the visual stimulus received by the eye. Let's break down the process of how these impulses are conveyed:

1. Structure of the Optic Nerves:
- The optic nerves are a pair of cranial nerves that originate from the back of each eye.
- They are composed of millions of individual nerve fibers bundled together.
- These fibers arise from specialized cells called ganglion cells in the retina, the light-sensitive layer at the back of the eye.

2. Pathway of the Impulses:
- When light enters the eye, it is focused by the lens onto the retina.
- The retina contains specialized cells called photoreceptors (rods and cones) that convert light into electrical signals.
- These electrical signals are then transmitted to the ganglion cells in the retina.
- The ganglion cells generate nerve impulses in response to the visual stimulus.
- The nerve impulses travel along the axons of the ganglion cells, which gather together to form the optic nerves.

3. Optic Chiasm:
- The optic nerves from each eye meet at a point called the optic chiasm, located at the base of the brain.
- At the optic chiasm, some of the nerve fibers from each optic nerve cross over to the opposite side of the brain.
- This crossing over is known as decussation and allows the brain to receive information from both eyes.

4. Transmission to the Brain:
- After the optic chiasm, the nerve fibers continue as the optic tracts.
- The optic tracts carry the nerve impulses towards the brain.
- They project to different regions of the brain, including the thalamus and the visual cortex.
- The thalamus acts as a relay station, processing and filtering the visual information before it reaches the visual cortex.
- Finally, the visual cortex, located in the occipital lobe, interprets the nerve impulses and allows us to perceive and make sense of the visual stimuli.

In summary, the optic nerves serve as the conduit for electric nerve impulses from the retina to the brain. They transmit visual information, encoded as electrical signals, which is essential for our perception and understanding of the visual world.