New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Optic nerve

The optic nerve is the nerve that transmits visual information from the retina to the brain. The optic nerve is composed of retinal ganglion cell axons and support cells. It leaves the orbit (eye) via the optic canal, running postero-medially towards the optic chiasm where there is a partial decussation (crossing) of fibers from the temporal visual fields of both eyes. Most of the axons of the optic nerve terminate in the lateral geniculate nucleus from where information is relayed to the visual cortex. The optic nerve contains 1.2 million nerve fibers. This number is low compared to the roughly 130 million receptors in the retina, and implies that substantial pre-processing takes place in the retina before the signals are sent to the brain through the optic nerve.

Related Stories
 


Health & Medicine News

August 7, 2026

Linus Pauling was widely mocked for claiming that vitamin C could fight cancer, especially after trials using vitamin C pills showed no benefit. Researchers now know that intravenous vitamin C reaches vastly higher concentrations and can behave more ...
Blocking the glycine transporter SLC6A20 restored important brain signaling and improved social, communication, and repetitive behaviors in autism-related mouse models. The treatment also worked in human brain organoids and showed lasting effects in ...
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people. Frequent contact was linked to greater ...
A new wearable patch may help people reach REM sleep faster and remain there longer without medication or surgery. In a study of 28 participants, the device shortened the time to REM by 43 minutes and extended it by about 16 minutes. Researchers ...
Beginning around age 50, the brain’s memory center appears to lose many of its longtime immune cells and replace them with more inflammatory ones. This surprising shift may help explain how normal aging sets the stage for Alzheimer’s disease and ...
A long-term brain study found that common risks such as smoking, high blood pressure, heart disease, and high blood lipids were strongly linked to damage associated with vascular dementia. The findings suggest that healthier lifestyle choices could ...
Genetic changes may set off a chain reaction that causes the spine’s natural shock absorbers to harden and deteriorate. Zebrafish with a faulty collagen-related gene developed mineral buildup and spinal fusion similar to human disc disease. ...
Tiny pollution particles from smoke, soot, and dust may worsen rheumatoid arthritis and raise the risk of painful flares, particularly after prolonged exposure. The findings suggest that avoiding poor air quality could become an important part of ...
A prescription form of THC helped many people with PTSD escape recurring trauma-related nightmares, with more than one-third reporting that the nightmares disappeared completely after ten weeks. The ...
A simple change in posture may subtly affect how people feel and make decisions. Participants who sat upright reported greater feelings of pride and took more successful risks in a virtual balloon game than those who hunched over. Most did not ...
Stanford researchers discovered immune cells in flatworms that explode within minutes, killing nearby bacteria and foreign cells before vanishing completely. Their unusually fast and localized attack ...
A specially engineered chewing gum reduced HPV by up to 93% and nearly eliminated two bacteria linked to head and neck cancer. The treatment preserved beneficial mouth bacteria, raising hopes for a safer and more affordable ...

Latest Headlines

updated 12:56 pm ET