After walking the Earth for a few hundred thousand years, humans might think they have seen it all. Not according to a team of scientists who claim to have experienced a color no one has seen before.
The bold — and contested — assertion follows an experiment in which researchers in the US had laser pulses fired into their eyes.
By stimulating individual cells in the retina, the laser pushed their perception beyond its natural limits, they said.
Their description of the color is not too arresting — the five people who have seen it call it blue-green — but that does not fully capture the richness of the experience, they said.
“We predicted from the beginning that it would look like an unprecedented color signal, but we didn’t know what the brain would do with it,” University of California, Berkeley electrical engineer Ren Ng said. “It was jaw-dropping. It’s incredibly saturated.”
The researchers shared an image of a turquoise square to give a sense of the color, which they named “olo,” but stressed that the hue could only be experienced through laser manipulation of the retina.
“There is no way to convey that color in an article or on a monitor,” said Austin Roorda, a vision scientist on the team. “The whole point is that this is not the color we see, it’s just not. The color we see is a version of it, but it absolutely pales by comparison with the experience of olo.”
Humans perceive the colors of the world when light falls on color-sensitive cells called cones in the retina.
There are three types of cones that are sensitive to long, medium and short wavelengths of light.
Natural light is a blend of multiple wavelengths that stimulate long, medium and short cones to different extents.
The variations are perceived as different colors. Red light primarily stimulates long cones, while blue light chiefly activates short cones. However, medium cones sit in the middle and there is no natural light that excites those alone.
The Berkeley team set out to overcome the limitation.
They began by mapping a small part of a person’s retina to pinpoint the positions of their medium cones. A laser is then used to scan the retina. When it comes to an medium cone, after adjusting for movement of the eye, it fires a tiny pulse of light to stimulate the cell, before moving on to the next cone.
The result, published in Science Advances, is a patch of color in the field of vision about twice the size of a full moon.
The color is beyond the natural range of the naked eye, because the M cones are stimulated almost exclusively, a state natural light cannot achieve. The name olo comes from the binary 010, indicating that of the long, medium and short cones, only the medium cones are switched on.
The claim left one expert bemused.
“It is not a new color,” City St George’s, University of London vision scientist John Barbur said. “It’s a more saturated green that can only be produced in a subject with normal red-green chromatic mechanism when the only input comes from medium cones.”
The work had “limited value,” he said.
The researchers believe the tool, named Oz vision after the Emerald City in the L. Frank Baum books, would help them probe basic science questions about how the brain creates visual perceptions of the world.
However, it might have other applications. Through bespoke stimulation of cells in the retina, researchers might learn more about color blindness or diseases that affect vision, such as retinitis pigmentosa.
Would the rest of the world get the chance to experience olo for themselves?
“This is basic science,” Ng said. “We’re not going to see olo on any smartphone displays or any TVs any time soon. And this is very, very far beyond VR headset technology.”
Two medieval fortresses face each other across the Narva River separating Estonia from Russia on Europe’s eastern edge. Once a symbol of cooperation, the “Friendship Bridge” connecting the two snow-covered banks has been reinforced with rows of razor wire and “dragon’s teeth” anti-tank obstacles on the Estonian side. “The name is kind of ironic,” regional border chief Eerik Purgel said. Some fear the border town of more than 50,0000 people — a mixture of Estonians, Russians and people left stateless after the fall of the Soviet Union — could be Russian President Vladimir Putin’s next target. On the Estonian side of the bridge,
Jeremiah Kithinji had never touched a computer before he finished high school. A decade later, he is teaching robotics, and even took a team of rural Kenyans to the World Robotics Olympiad in Singapore. In a classroom in Laikipia County — a sparsely populated grasslands region of northern Kenya known for its rhinos and cheetahs — pupils are busy snapping together wheels, motors and sensors to assemble a robot. Guiding them is Kithinji, 27, who runs a string of robotics clubs in the area that have taken some of his pupils far beyond the rural landscapes outside. In November, he took a team
SHOW OF SUPPORT: The move showed that aggression toward Greenland is a question for Europe and Canada, and the consequences are global, not just Danish, experts said Canada and France, which adamantly oppose US President Donald Trump’s wish to control Greenland, were to open consulates in the Danish autonomous territory’s capital yesterday, in a strong show of support for the local government. Since returning to the White House last year, Trump has repeatedly insisted that Washington needs to control the strategic, mineral-rich Arctic island for security reasons. Trump last month backed off his threats to seize Greenland after saying he had struck a “framework” deal with NATO chief Mark Rutte to ensure greater US influence. A US-Denmark-Greenland working group has been established to discuss ways to meet Washington’s security concerns
Civil society leaders and members of a left-wing coalition yesterday filed impeachment complaints against Philippine Vice President Sara Duterte, restarting a process sidelined by the Supreme Court last year. Both cases accuse Duterte of misusing public funds during her term as education secretary, while one revives allegations that she threatened to assassinate former ally Philippine President Ferdinand Marcos Jr. The filings come on the same day that a committee in the House of Representatives was to begin hearings into impeachment complaints against Marcos, accused of corruption tied to a spiraling scandal over bogus flood control projects. Under the constitution, an impeachment by the
RSS