Featured Research

from universities, journals, and other organizations

Vision restored with total darkness in kittens with amblyopia

Date:
February 14, 2013
Source:
Cell Press
Summary:
Restoring vision might sometimes be as simple as turning out the lights. That's according to a study in which researchers examined kittens with a visual impairment known as amblyopia before and after they spent 10 days in complete darkness.

Depriving normal visual experience in one eye early in life produces a reduction in visual acuity (amblyopia) for that eye (blue circles) while the acuity of the other eye is normal (red). The visual acuity of the amblyopic eye remains low compared to the fellow eye, but after immersion in complete darkness the amblyopic eye very quickly recovers to match the visual acuity attained by the normal eye.
Credit: Current Biology, Duffy et al.

Restoring vision might sometimes be as simple as turning out the lights. That's according to a study reported on February 14 in Current Biology, a Cell Press publication, in which researchers examined kittens with a visual impairment known as amblyopia before and after they spent 10 days in complete darkness.

Researchers Kevin Duffy and Donald Mitchell of Dalhousie University in Canada believe that exposure to darkness causes some parts of the visual system to revert to an early stage in development, when there is greater flexibility.

"There may be ways to increase brain plasticity and recover from disorders such as amblyopia without drug intervention," Duffy says. "Immersion in total darkness seems to reset the visual brain to enable remarkable recovery."

Amblyopia affects about four percent of the general population and is thought to develop when the two eyes do not see equally well in early life, as the connections from the eyes to visual areas in the brain are still being refined. Left untreated, that imbalance of vision can lead to permanent vision loss.

In the new study, the researchers examined kittens with amblyopia induced by experimentally depriving them of visual input to one eye. After those animals were plunged into darkness, their vision made a profound and rapid recovery. Further examination suggested that the restoration of vision depends on the loss of neurofilaments that hold the visual system in place. With those stabilizing elements gone, the visual system becomes free to correct itself.

Darkness therapy holds promise for the treatment of children with amblyopia, the researchers say, but don't try this at home. They think that the darkness must be absolute to work, with no stray light at any time. It is also important to address the original cause of the amblyopia first, and to ensure that a period of darkness will not harm an individual's good eye.

The researchers are still working out just how much darkness is required, and for how long. Regardless, they say it is unlikely that a drug could ever adequately mimic the effects of darkness that they've seen.

"The advantage of a simple nonpharmacological sensory manipulation, such as a period of darkness, is that it may initiate changes in a constellation of molecules in a beneficial temporal order and in appropriate brain regions," they write.


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kevin R. Duffy, Donald E. Mitchell. Darkness Alters Maturation of Visual Cortex and Promotes Fast Recovery from Monocular Deprivation. Current Biology, 14 February 2013 DOI: 10.1016/j.cub.2013.01.017

Cite This Page:

Cell Press. "Vision restored with total darkness in kittens with amblyopia." ScienceDaily. ScienceDaily, 14 February 2013. <www.sciencedaily.com/releases/2013/02/130214133916.htm>.
Cell Press. (2013, February 14). Vision restored with total darkness in kittens with amblyopia. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2013/02/130214133916.htm
Cell Press. "Vision restored with total darkness in kittens with amblyopia." ScienceDaily. www.sciencedaily.com/releases/2013/02/130214133916.htm (accessed April 25, 2014).

Share This



More Health & Medicine News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins