Sunday, February 17, 2008
Whose voice is that? Scientists discover 'voice' area in the brain of nonhuman primate
For vocal animals, recognising species-specific vocalizations is important for survival and social interactions. In humans, a ‘voice' region has been identified that is sensitive to human voices and vocalizations. As this region also strongly responds to speech, it is unclear whether it is tightly associated with linguistic processing and thus unique to humans.
Using functional magnetic-resonance imaging (fMRI) of macaque monkeys (Old World primates) researcher at the Max-Planck Institute for Biological Cybernetics discovered a high-level auditory region that prefers species-specific vocalizations over other vocalizations and sounds. This region not only showed sensitivity to the ‘voice’ of the species, but also to the vocal identify of individuals belonging to the same species.
These results establish functional relationships with the human-voice region and support the notion that for different primate species certain areas of the brain are adapted for recognizing communication signals from member of the same species.
The research group in the laboratory of Nikos Logothetis used a non-invasive imaging technique, which has become a standard tool for understanding human brain function, to image macaque monkeys, one of our distant primate relatives. In their study the authors describe the discovery of a monkey "voice" area, a part of the brain that appears to be important for an individual in recognising verbal communications from other members of their species.
The study shows that the voice area wasn’t active to just any sound. Instead, this brain area preferred vocalizations from animals belonging to the listener’s species, preferring to process the vocal sounds that hold special meaning for "conspecific" individuals (i.e. belonging to the same species). Hence, this brain region plays a central role in the communication between members of a species, supporting their social interactions and contributing to the survival of the species.
In addition, the scientists also found that this voice area is sensitive to the identity of the individual that was vocalizing. Consequently, the scientists conclude that this area can support multiple verbal recognition abilities, such as helping the listener to recognize the acoustical signature or the 'voice of the species', as well as the voices of different individuals.
The discovery of a voice area in the monkey brain also opens a window into human verbal communication and brain function. Many people doubt that there is much to be learned from other animals about human verbal communication and language. Contrasting this, these findings provide direct parallels between how the brains of humans and non-human animals process communication signals. This study strongly argues that voice areas were evolutionarily conserved in primates, challenging the notion that higher-level verbal communication can only be achieved by the human brain.
"This discovery in monkeys and the link to the human work is exciting because the animals are now helping us to understand how this brain area recognizes voices in a way that we cannot in humans," says Dr. Petkov, who led the research study. The researchers believe that their discovery will provide pathways for understanding clinical conditions such as phonagnosia, where patients show deficits in voice recognition and verbal communication prohibiting them from recognizing the voice of someone that they know.
Posted by SANJIDA AFROJ at 4:29 PM
A farmer works in his field in Mexico City. The US National Academy of Engineering has announced the grand challenges for engineering in the 21st century that, if met, would improve people's lives. The list of 14 tasks was unveiled Friday by a diverse committee of experts from around the world, convened at the request of the US National Science Foundation.
The US National Academy of Engineering has announced the grand challenges for engineering in the 21st century that, if met, would improve people's lives.
"Tremendous advances in quality of life have come from improved technology in areas such as farming and manufacturing," said committee member and Google co-founder Larry Page. "If we focus our effort on the important grand challenges of our age, we can hugely improve the future."
The panel, some of the most accomplished engineers and scientists of their generation, was established in 2006 and met several times to discuss and develop the list of challenges.
Through an interactive Web site, the effort received worldwide input from prominent engineers and scientists, as well as from the general public, over a one-year period.
The panel's conclusions were reviewed by more than 50 subject-matter experts.
The final choices fall into four themes that are essential for humanity to flourish: sustainability, health, reducing vulnerability, and joy of living.
The committee did not attempt to include every important challenge, members said, nor did it endorse particular approaches to meeting those selected. Rather than focusing on predictions or gadgets, the goal was to identify what needs to be done to help people and the planet thrive.
"We chose engineering challenges that we feel can, through creativity and commitment, be realistically met, most of them early in this century," said committee chair and former US secretary of defense William Perry.
"Some can be, and should be, achieved as soon as possible," he added.
The committee decided not to rank the challenges. But their list includes making solar energy affordable, providing energy from fusion, managing the nitrogen cycle, providing access to clean water around the world, reverse-engineering the human brain, preventing nuclear terror and securing cyberspace among others.
NAE is offering the public an opportunity to vote on which one they think is most important and to provide comments at the project Web site: http://www.engineeringchallenges.org .
"Meeting these challenges would be 'game changing,'" said NAE president Charles Vest. "Success with any one of them could dramatically improve life for everyone."
Posted by SANJIDA AFROJ at 4:22 PM
Salty water may have snuffed out life on Mars: scientistsLife on Mars may have been snuffed out early on because the water there was too salty, a biologist involved in exploring the red planet said here Saturday.
"Mars has been a very dry place for a very long time," said Andrew Knoll, an expert member of a team operating two US robots that are currently exploring Mars. "The best place to look for life is in the earliest history," he added.
"It was really salty and difficult for micro-organisms to survive in this water," he told reporters, citing discoveries by the robots which back up earlier theories that strong concentrations of minerals killed off life.
He was speaking on the sidelines of the annual meeting of the American Association for the Advancement of Science (AAAS) that opened here Thursday.
The discoveries by the robots roving the planet, dubbed Spirit and Opportunity, cannot confirm whether life ever existed on Mars, however.
"If there is a habitable niche, it's underground" on the planet, said the head scientist for the mission, astronomist Steven Squyres of Cornell University in New York state. Life anywhere else would leave atmospheric traces of gas produced by organisms.
According to another theory cited by Knoll, "a large meteorite may have sterilized life on Mars."
In December the US space agency NASA said the Sprint robot had discovered nearly pure silicon on Mars.
Squyres said this silicon forms near natural hot water sources or volcanic outlets, which give off natural gas. On Earth, living microbes are always found in such situations.
The roving robots are still going despite having passed their expected performance life by three months. They have been operating for four years.
Posted by SANJIDA AFROJ at 4:04 PM
Strapped into the back seat of an F-16 fighter jet as it tore through the sky at more than 700 miles an hour, I listened intently to Col. Bill "Thunder" Thornton, who sat up front, his hands on the controls.
"We are three miles from release," his voice crackled in my helmet. Then he asked me how I was holding up.
"Doing good here," I told him, speaking into the microphone in my oxygen mask as my hands reached for something stable to hold on to.
"You should be watching the bottom of his aircraft, and the weapon should be coming off shortly," the colonel advised.
Despite a murmur of nausea, my eyes focused intently on the belly of the F-15E Strike Eagle that was flying just a few feet from our wing tip. A single bomb hung from the "Thunder One, clear to release," I heard in my headset, recognizing the voice of Maj. Verun "Stinger" Puri, the commander of this mission and the pilot of the F-15E.
"Pickle," he said, using the familiar code word for release, "weapon away." As he said it, the 4-foot-long bomb fell free from the fighter jet, and for a moment it seemed to float in the air. I strained to follow its path as it flipped itself over and released a set of wings before plunging out of sight.
"Weapon is initiating glide," said Puri in that calm pilot drone immortalized in the movie "The Right Stuff."
"It's started to nose over now," added Thornton from the front seat.
Fifteen thousand feet below, in the Command Control Center of Eglin Air Force Base, the eyes of the Bomb Development Team were glued to a series of tracking screens. They were watching a solitary truck sitting somewhere on the base's 900-square-mile firing range. On the roof of the truck sat an orange highway cone: the target.
Smaller Is Better
From my front-row seat in the sky I am witnessing the test of the latest weapon in the arsenal of the U.S. Air Force. They call it the Small Diameter Bomb, or SDB. As its name suggests, it is a very small bomb, carrying less than 40 pounds of explosives. By comparison, the JDAM (short for Joint Direct Attack Munition), the workhorse of the current wars in Iraq and Afghanistan, comes in a variety of sizes, the smallest of which carries 200 pounds of explosives.
Preparation for today's mission began long before sunrise when a single SDB was rolled out and mounted on the F-15. A few early versions of these new small bombs have been in the field in Iraq and Afghanistan since last November, although only about 14 have been dropped. This test flight is to check out a new guidance system for this very new weapon, one that is cheaper and they hope better.
As the Air Force now sees it, in today's warfare smaller is better. With these new Small Diameter Bombs, it hopes to accomplish three things at once: get more weapons on each aircraft; fire those weapons from much further away than JDAMs allow; and, critically, with much less explosive inside, aim to strike with surgical precision.
What that last point means is that when the new SDB strikes a target, its blast range is about 50 feet. Compare that to the impact radius of the smallest JDAM: 100 feet and the 2,000-pound JDAM: 175 feet.
To understand why that matters you simply have look at some of the Air Force's "successful" airstrikes that have had catastrophic consequences. In one Afghanistan bombing earlier this year, two 2,000-pound bombs not only killed their targets, they also killed nine innocent civilians in a neighboring house, including four women and four children. In warfare they call that collateral damage, and it is uncomfortably common. If numbers are a guide, it is also getting worse: In 2007 airstrikes by U.S. and NATO forces in Afghanistan killed nearly 300 civilians, compared to 116 in 2006.
'Responsible to the Civilian Population
The day before the test flight, I met with Col. Dick Justice, the man in charge of developing Small Diameter Bombs. As he showed me a model of the very small bomb, he candidly told me that the Air Force cannot afford to ignore the consequences of collateral damage.
"Part of warfare is you have to be responsible to the civilian population," said Justice. "We are not at war with a population. We are not at war with the Iraqi people or the people of Afghanistan. We are at war with people who are hiding within their communities. So you have to be very sensitive to the damages that you cause that are not against the intended target."
In short, the U.S. military has learned that the anger incited when bombs kill innocent civilians plays right into the hands of the insurgents who are always eager to welcome new recruits.
"We are looking to minimize those effects that we don't intend," said the colonel.
Even critics of this war say the new SDB is a welcome addition to the Air Force arsenal. One of them is former Pentagon intelligence analyst Marc Garlasco, now senior military analyst for Human Rights Watch.
"It is not the role of Human Rights Watch to advocate for a weapon or to say 'You know, this is a better way to bomb.' But clearly it shows that the Air Force is taking the right steps as far as improving civilian
protections," said Garlasco. "They are recognizing that you don't want to kill civilians in conflict, that it's counterproductive for their work and what they need to do. So absolutely it's a step in the right direction." 'Direct Hit!'
Back on the ground in the Control Center the bomb suddenly came into view on the giant screens.
"5, 4, 3, 2, 1," said a voice over the room's loudspeaker.
"Impact!" At that very moment cameras recorded a bright flash and a huge boom.
The bomb hit the orange cone right in the center. Even though this was a test bomb with just a fuse and no explosives, the cab of the truck was destroyed.
"Direct hit!" said the voice on the loudspeakers. "Very nice. Beautiful. Rock 'n' roll!"
This is exactly what they mean when they talk about a "smart bomb."
Technology has brought warfare a very long way from those carpet bombs that were dropped randomly from the skies in Vietnam. From 15,000 feet in the sky and 20 miles away, the computer guidance system steered the SDB to within an inch or two of its target.
"The bomb will go where it is told to go," said Justice.
But even with staggering advances in technology, a bomb is only as smart as the intelligence the military feeds it. That means the military has to know precisely where the bad guys are. And in the guerilla warfare of Iraq and Afghanistan, that is still the hardest part.
of Human Rights Watch says that is why the Air Force cannot afford to get too confident about its new technology.
"Well, historically it's been problematic," said Garlasco. "When you look at what's gone on in recent conflicts, we've seen a lot of the high collateral damage when they thought they knew a bad guy was in a place, and either he wasn't, or they knew where he was but they didn't really know where the civilians were."
For all of the investment in technology, Garlasco says the Air Force has to continue to put just as much emphasis on developing better intelligence by working closely with U.S. troops on the ground.
Less than two hours after the jets left, they returned to the airfield at Eglin. Their part of the mission: accomplished without incident. While today's test seemed to go flawlessly, it will take weeks analyze the data.
Meanwhile, the next generation of Small Diameter Bomb is already in early development. The FLM, or Focused Lethality Munition, will take surgical precision to a new level. It will be made of hardened plastics that disintegrate on explosion, eliminating the deadly metal fragments, or shrapnel, that causes so much unintended damage and destruction. Clearly, the Air Force is determined to refine what it believes will be the surgical strike weapon of choice for 21st century warfare.
Posted by SANJIDA AFROJ at 3:08 PM
Japanese electronics maker Toshiba might withdraw its HD DVD next-generation video format, Kyodo News agency reported Saturday.
The report cited unidentified individuals from the industry as saying Toshiba Corp. is reviewing its operations, with the timing of the withdrawal to be decided later, depending on U.S. demand for its HD DVD products and other factors.
Calls went unanswered at Toshiba Corp.'s Tokyo office, which was closed for the weekend.
HD DVD has been competing against the Blu-ray technology, backed by Sony Corp., other makers and five major Hollywood movie studios.
Recently the Blu-ray disc format has been gaining market share, while Toshiba has been forced to slash prices to sell its HD DVD machines. A Toshiba pullout would signal the almost certain defeat of HD DVD to Blu-ray.
On Friday, Wal-Mart Stores Inc., the largest U.S. retailer, said it will sell only Blu-ray DVDs and hardware and no longer carry HD DVD offerings.
The announcement came five days after Netflix Inc. said it will cease carrying rentals in HD DVD. Several major U.S. retailers have made similar decisions, including Target Corp. and Blockbuster Inc.
Last month, Warner Bros. Entertainment decided to release movie discs only in the Blu-ray format, becoming the latest studio to reject HD DVD.
Warner Bros., owned by Time Warner Inc., had been the only remaining Hollywood studio releasing high-definition DVDs in both formats.
Both formats deliver crisp, clear high-definition pictures and sound, but they are incompatible with each other, and neither plays on older DVD players.
Only one format has been expected to emerge as the winner, much like VHS trumped Sony's Betamax in the video format battle of the 1980s.
An announcement about Toshiba's HD DVD players and recorders is due next week, says Japanese public broadcaster NHK.
Toshiba has halted production of HD DVD players and recorders and is close to making a decision on whether to throw in the towel on the high-definition movie disc format, Japanese public broadcaster NHK reported Saturday evening.
The decision, which NHK said will likely cost the company several tens of billions of dollars, is being made in the face of flagging support by movie studios and major U.S. retailers.
"We are making considerations following the impact on sales of Warner's announcement but we haven't made any decision," said Keisuke Ohmori, a spokesman for Toshiba, when reached on Saturday evening. He was referring to the January decision by Warner Bros to stop issuing movies on HD DVD and go solely with Blu-ray Disc.
Other local media reports on Saturday said an official announcement from Toshiba is likely in the coming week.
HD DVD has been battling Blu-ray Disc for just under two years to become the defacto replacement for DVD for high-definition video. HD DVD is backed by Toshiba and a handful of other companies including Microsoft and Intel but Blu-ray Disc counted a larger number of consumer electronics heavy hitters. The main backer of the format is Sony and other supporters include Panasonic, Sharp, Samsung, LG and Philips.
Both formats delivered a similar audio and video quality and the main difference comes down to the movies available on each format. Most movie studios have taken one side or the other so consumers are left with a difficult decision. As a result many have walked away from stores with neither an HD DVD or Blu-ray Disc player and the market has performed poorly.
The Warner Bros decision in January has been seen by many as the beginning of the end for HD DVD. With Warner pulling out HD DVD only two of the major Hollywood studios, Paramount and Universal, are left backing the format.
In the weeks since the Warner announcement things have gotten worse for HD DVD. In the last week Netflix, an Internet-based movie rental company in the U.S., said it would cease supporting HD DVD and then on Friday Wal-Mart, the largest retailer in the U.S., said it would stop selling HD DVD in favor of Blu-ray Disc.
Posted by SANJIDA AFROJ at 1:29 PM