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Dec. 16th, 2002
Oh yeah, before I forget....
Dec. 16th, 2002 07:06 pmI managed to make it to church yesterday, the church of my adolescence. It was so good to see people I've not seen in a decade.
The strangest thing of the service was that the sermon was delivered with the aid of Powerpoint. In the middle of church, I found myself watching a three- or five-minute clip of A Christmas Story. Very odd.
The strangest thing of the service was that the sermon was delivered with the aid of Powerpoint. In the middle of church, I found myself watching a three- or five-minute clip of A Christmas Story. Very odd.
race is in the eye of the beholder
Dec. 16th, 2002 07:39 pmRace Not Reflected in Genes, Study Finds
The idea of race is not reflected in a person's genes, Brazilian researchers said on Monday, confirming what scientists have long said -- that race has no meaning genetically.
The Brazilian researchers looked at one of the most racially mixed populations in the world for their study, which found there is no way to look at someone's genes and determine his or her race. Brazilians include people of European, African and Indian, or Amerindian, descent.
"There is wide agreement among anthropologists and human geneticists that, from a biological standpoint, human races do not exist," Sergio Pena and colleagues at the Universidade Federal de Minas Gerias in Brazil and the University of Porto in Portugal wrote in their report, published in the Proceedings of the National Academy of Sciences.
"Yet races do exist as social constructs," they said.
They found 10 gene variations that could reliably tell apart, genetically, 20 men from northern Portugal and 20 men from Sao Tome island on the west coast of Africa.
But the genetic differences did not have anything to do with physical characteristics such as skin or hair color, the researchers found.
[...] "In essence our data indicate that, in Brazil as a whole, color is a weak predictor of African ancestry," they concluded.
"Our study makes clear the hazards of equating color or race with geographical ancestry and using interchangeably terms such as white, Caucasian and European on one hand, and black, Negro or African on the other, as is often done in scientific and medical literature."
The idea of race is not reflected in a person's genes, Brazilian researchers said on Monday, confirming what scientists have long said -- that race has no meaning genetically.
The Brazilian researchers looked at one of the most racially mixed populations in the world for their study, which found there is no way to look at someone's genes and determine his or her race. Brazilians include people of European, African and Indian, or Amerindian, descent.
"There is wide agreement among anthropologists and human geneticists that, from a biological standpoint, human races do not exist," Sergio Pena and colleagues at the Universidade Federal de Minas Gerias in Brazil and the University of Porto in Portugal wrote in their report, published in the Proceedings of the National Academy of Sciences.
"Yet races do exist as social constructs," they said.
They found 10 gene variations that could reliably tell apart, genetically, 20 men from northern Portugal and 20 men from Sao Tome island on the west coast of Africa.
But the genetic differences did not have anything to do with physical characteristics such as skin or hair color, the researchers found.
[...] "In essence our data indicate that, in Brazil as a whole, color is a weak predictor of African ancestry," they concluded.
"Our study makes clear the hazards of equating color or race with geographical ancestry and using interchangeably terms such as white, Caucasian and European on one hand, and black, Negro or African on the other, as is often done in scientific and medical literature."
hardwired to zone out
Dec. 16th, 2002 07:46 pmBrain Appears to Have 'Daydreaming' Mode
[my first reaction: Well, duh!]
Much as a car's engine hums along even when it's parked in neutral, the brain seems to contain a "default mode" in which certain regions become more active at rest, US researchers report.
"During rest, these regions appear to be interacting, because they change at similar rates," lead author Dr. Michael D. Greicius of Stanford University in California told Reuters Health.
Intriguingly, the behavior of these brain regions bears a certain resemblance to what one would expect from brain areas that make up human consciousness, Greicius added.
The default mode network supported in the current study generally increases its activity when the brain is at rest, then drops in activity once people are called to a certain task. In a similar way, Greicius said, a person could be daydreaming or following a stream of consciousness, but those activities would be zapped away as soon as the person was called to action, perhaps by a ringing telephone.
In addition, some of the brain regions that may form parts of the so-called default mode network have shown in previous studies to be involved in certain aspects of consciousness, Greicius added. For instance, one of the brain regions looked at in the current study, the posterior cingulate cortex (PCC), has been shown to play a role in the brain processes by which people recall memories. In addition, PCC activity tends to peter out as people lose consciousness when sedated.
[The posterior cingulate cortex is also primarily involved during a DXM trip, if not other dissociative experiences.]
[my first reaction: Well, duh!]
Much as a car's engine hums along even when it's parked in neutral, the brain seems to contain a "default mode" in which certain regions become more active at rest, US researchers report.
"During rest, these regions appear to be interacting, because they change at similar rates," lead author Dr. Michael D. Greicius of Stanford University in California told Reuters Health.
Intriguingly, the behavior of these brain regions bears a certain resemblance to what one would expect from brain areas that make up human consciousness, Greicius added.
The default mode network supported in the current study generally increases its activity when the brain is at rest, then drops in activity once people are called to a certain task. In a similar way, Greicius said, a person could be daydreaming or following a stream of consciousness, but those activities would be zapped away as soon as the person was called to action, perhaps by a ringing telephone.
In addition, some of the brain regions that may form parts of the so-called default mode network have shown in previous studies to be involved in certain aspects of consciousness, Greicius added. For instance, one of the brain regions looked at in the current study, the posterior cingulate cortex (PCC), has been shown to play a role in the brain processes by which people recall memories. In addition, PCC activity tends to peter out as people lose consciousness when sedated.
[The posterior cingulate cortex is also primarily involved during a DXM trip, if not other dissociative experiences.]