A single, specific memory has been wiped from the brains of rats, leaving other recollections intact.
The study adds to our understanding of how memories are made and altered in the brain, and could help to relieve sufferers of post-traumatic stress disorder (PTSD) of the fearful memories that disrupt their lives.
March 14, 2007
March 5, 2007
This composite-picture traces the way the sun’s position in the sky changes, even though each picture was taken at the same time each day:
Here’s the full explanation.
February 22, 2007
Fisherman in New Zealand have hauled in the largest giant squid ever captured. It’s over 32 feet long and weighs close to 1000 pounds:
A special feature in Nature revisits the successful cloning of Dolly the sheep, which sparked a media frenzy ten years ago. The article explains how the science of cloning has shifted into stem cells and other research, instead of wholesale cloning.
Back in early 1997, none of Wilmut and his colleagues, the referees who reviewed their paper, or the Nature editors who oversaw it, anticipated the huge public reaction to the cloning of Dolly. Scientists in the field saw her birth as an incremental advance — in large part because one year earlier, Nature had published a paper from Wilmut’s group reporting the cloning of two lambs, Morag and Megan, using nuclei from embryonic cells.
“I always maintained that Dolly was expected and Morag and Megan were truly surprising,” says Davor Solter, director of the Max Planck Institute for Immunobiology in Freiburg, Germany. Solter wrote a News & Views article in Nature about the paper on Morag and Megan, suggesting that it was time to start thinking about the implications and uses of cloning mammals from adult cells.
The feature also has a sweet Cloning Timeline.
February 15, 2007
This CNET photo article highlights the impressive leaps made by the synthetic diamond industry. Technology has advanced to the point where diamond makers can create perfect “cultured” diamonds in a factory — much like pearls that are grown on a pearl farm.
Hopefully the stigma associated with “fake” diamonds will disappear with enough time, and buying diamonds will no longer be quite so stupid.
(You too, Kanye. Awesome song!)
February 9, 2007
In an extraordinary archeological find, two embracing skeletons were unearthed recently in Italy. “The pair, almost certainly a man and a woman, are thought to have died young as their teeth were mostly intact, said chief archaeologist Elena Menotti.” Judging by the age of the couple, perhaps it’s Adam and Eve? Seems unlikely they would have made it all the way to Italy, but who knows?
“It’s an extraordinary case,” said Ms Menotti. “There has not been a double burial found in the Neolithic period, much less two people hugging – and they really are hugging,” she told Reuters news agency.
January 29, 2007
January 9, 2007
Via Cognitive Daily, an interesting report on the possibility that testosterone and the desire to “defend the home turf” give home teams an advantage. The study was conducted in England, so they tested players in the Premiership. The results are impressive:
Neave and Wolfson tested 17 members of an English club team before home and away games. Each player provided saliva samples and filled out a simple emotion questionnaire. Among the 10 players who took the field during both games, testosterone levels in the saliva were significantly higher before the home game (9.93 ng/dl) than the away game (5.79 ng/dl). There were no significant differences in any of the self-reported emotions, ranging from calmness to enthusiasm.
Also, there’s a nice graph:
I don’t think anyone will forward the interpretation that this is the only factor at play in home field advantage, but the results are fascinating.
December 20, 2006
A brief piece in The Economist summarizes current trends in neuroscience and it affects the way we think about ourselves an our decisions:
For millennia the question of free will was the province of philosophers and theologians, but it actually turns on how the brain works. Only in the past decade and a half, however, has it been possible to watch the living human brain in action in a way that begins to show in detail what happens while it is happening (see survey). This ability is doing more than merely adding to science’s knowledge of the brain’s mechanism. It is also emphasising to a wider public that the brain really is a just mechanism, rather than a magician’s box that is somehow outside the normal laws of cause and effect.
Science is not yet threatening free will’s existence: for the moment there seems little prospect of anybody being able to answer definitively the question of whether it really exists or not. But science will shrink the space in which free will can operate by slowly exposing the mechanism of decision making.
The link within the text points to another piece in the same issue, which deals with the question of identity in light of the findings of neuroscience:
On September 13th 1848 a navvy called Phineas Gage was helping to build a railway in Vermont. As gang foreman, he had the job of setting explosive charges to blast a path through the hills near a town called Cavendish. While he was tamping down one of the charges with an iron bar, it went off prematurely, driving the bar clean through his head.
Accidents on construction projects happen all the time. The reason that people remember Gage’s is that he survived it. Or, rather, his body survived it. For the Gage that returned to work was not the Gage who had stuck the tamping rod into that explosive-filled hole. Before, he had been a sober, industrious individual, well respected and destined for success. Afterwards, he was a foul-mouthed drunkard, a drifter and a failure. His identity had been changed in a specific way by specific damage to a specific part of his brain.
December 12, 2006
Jamie directed me to this fascinating article from Sunday’s Times: DNA Gatherers Hit Snag: Tribes Don’t Trust Them. It concerns the efforts of the National Geographic Society, which is attempting to gather DNA from hundreds of the earth’s indigenous tribes with the hope of tracing their genetic history and the paths of migration that led them to their current home. Unfortunately, the scientists are running into trouble, mainly with tribes who do not want to have their historical identity exposed, fearing that it will spoil their claims to legitimacy and special standing.
Comparing the DNA of large numbers of American Indians might reveal whether their ancestors were from a single founding population, and when they reached the Americas. And knowing the routes and timing of migrations within the Americas would provide a foundation for studying how people came to be so different so quickly.
But almost every federally recognized tribe in North America has declined or ignored Dr. Schurr’s invitation to take part. “What the scientists are trying to prove is that we’re the same as the Pilgrims except we came over several thousand years before,” said Maurice Foxx, chairman of the Massachusetts Commission on Indian Affairs and a member of the Mashpee Wampanoag. “Why should we give them that openly?”
Some American Indians trace their suspicions to the experience of the Havasupai Tribe, whose members gave DNA for a diabetes study that University of Arizona researchers later used to link the tribe’s ancestors to Asia. To tribe members raised to believe the Grand Canyon is humanity’s birthplace, the suggestion that their own DNA says otherwise was deeply disturbing.