Why blinking doesn't dim the lights

"We perceive coherence and not transient blindness because the brain connects the dots for us," said researcher David Whitney.
By Brooks Hays   |   Jan. 20, 2017 at 4:47 PM

Jan. 20 (UPI) -- Most people blink every few seconds, and yet our vision remains mostly constant. Our visual experience isn't characterized by a constant back-and-forth between light and darkness.

What accounts for our seamless visuals?

New research suggests the brain works overtime to stabilize our vision. More than simply adjust for changing light levels, the brain also reorients the eyes each time they roll to the back of the socket and forward again as we blink.

"Our eye muscles are quite sluggish and imprecise, so the brain needs to constantly adapt its motor signals to make sure our eyes are pointing where they're supposed to," Gerrit Maus, an assistant professor of psychology at Nanyang Technological University in Singapore, said in a news release. "Our findings suggest that the brain gauges the difference in what we see before and after a blink, and commands the eye muscles to make the needed corrections."

To better understand how human eyes handle the interruption of a blink, researchers had participants stare at a single dot on a screen as infrared cameras tracked the movement of their eyes.

During each blink, the dot moved -- imperceptibly -- one centimeter to the right. As the cameras revealed, the eyes of each participant instantly adjusted to the dot's new position. After 30 blinks, participants' eyes adjusted one centimeter to the right even when the dot failed to move. The eyes had become trained, and predicted an unnecessary adjustment before recalibrating.

"Even though participants did not consciously register that the dot had moved, their brains did, and adjusted with the corrective eye movement," Maus said. "These findings add to our understanding of how the brain constantly adapts to changes, commanding our muscles to correct for errors in our bodies' own hardware."

The findings, published in the journal Current Biology, suggest it is our brain's ability to constantly correct the failure of our eye muscles that explains the stability of human vision.

"We perceive coherence and not transient blindness because the brain connects the dots for us," said study co-author David Whitney, a psychology professor at the University of California, Berkeley.

© 2017 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.

Astronomer looks for alien life in Wolf 1061 system

The latest findings suggest Wolf 1061c is more like Venus than Earth.
By Brooks Hays   |   Jan. 20, 2017 at 4:04 PM

Jan. 20 (UPI) -- San Francisco State University astronomer Stephen Kane, one of Earth's best "planet hunters," recently turned his attention to the Wolf 1061 system, a collection of planets surrounding an M-class red dwarf star.

Kane and his colleagues at San Francisco State are mostly interested in Wolf 1061c, which lies entirely within the system's habitable zone. The habitable zone, in which water could be found in liquid form, varies depending on the size and strength of the parent star -- too close and water vapor and atmosphere is burned away, too far and water remains locked up in ice form.

Kane's research team recently published their analysis of Wolf 1061c in the Astrophysical Journal.

"The Wolf 1061 system is important because it is so close and that gives other opportunities to do follow-up studies to see if it does indeed have life," Kane said in a news release.

The Wolf 1061 system lies 14 light-years from Earth.

The latest findings suggest Wolf 1061c is more like Venus than Earth. If it has life, it's not a very pleasant existence. That's because the exoplanet is positioned on the inner edge of the system's habitable zone. Water can only last so long on a planet so close to its sun.

"It's close enough to the star where it's looking suspiciously like a runaway greenhouse," Kane said.

The runaway greenhouse effect describes the process of overheating, as solar energy becomes trapped beneath a planet's atmosphere. Venus once hosted oceans, but all its water has since boiled away as a result of the greenhouse effect.

Scientists say the chance of life existing on Wolf 1061c can't yet be discounted. Like Earth, the exoplanet's orbit is shifty, triggering periodic changes in its atmosphere -- only Wolf 1061c's shifts happen on a more more rapid time scale. Periods of cooling may be sufficient to cool and stabilize the exoplanet's atmosphere.

Per usual, more research is needed.

© 2017 United Press International, Inc. All Rights Reserved. Any reproduction, republication, redistribution and/or modification of any UPI content is expressly prohibited without UPI's prior written consent.
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