Nouvelles interessantes de Science

Tres interessant! on dirait que le cerveau ne s'arrete jamais de se developper...

Brain changes at puberty 'help to develop intellectual machinery'
By Steve Connor, Science Editor
Published: 08 September 2006

The brain undergoes dramatic changes during adolescence which continue into a person's twenties, according to studies.

"It's not true that the brain stops developing at the age of five, which was a very established myth until about six years ago," said Sarah Blakemore, a neuroscientist at University College London. "The brain continues to undergo a massive wave of development at the onset of puberty and continues right through adolescence and into the early twenties and even thirties in some brain areas."

Two studies of teenagers have shown that their brains undergo significant reorganisation which helps them to develop the intellectual machinery for understanding their own emotions and the feelings of others.

"One of the brain regions that undergoes this dramatic development during adolescence is the pre-frontal cortex, the part of the front of the brain that makes us human," said Dr Blakemore. "It's involved in all sorts of high-level cognitive functions like making decisions and also understanding other people and social awareness."

Brain scans of teenagers and adults show that as, people get older, they begin to use the pre-frontal cortex at the expense of the superior temporal sulcus, at the back of the brain. "It's as if the pattern of brain activity shifts from the back of the brain to the front of the brain during adolescence to do this kind of empathy task," said Dr Blakemore.

A second study found that the brains of teenagers changed as they grow older in a way that makes them more efficient at seeing things from other people's perspectives. "The studies suggest that it's not just hormones that are causing teenagers to be their typical selves, it could also be the fact that their brains are developing as well," said Dr Blakemore. "Nobody knows whether it's genetically pre-programmed or whether it is influenced by the environment. Possibly there's a bit of both."

The brain undergoes dramatic changes during adolescence which continue into a person's twenties, according to studies.

"It's not true that the brain stops developing at the age of five, which was a very established myth until about six years ago," said Sarah Blakemore, a neuroscientist at University College London. "The brain continues to undergo a massive wave of development at the onset of puberty and continues right through adolescence and into the early twenties and even thirties in some brain areas."

Two studies of teenagers have shown that their brains undergo significant reorganisation which helps them to develop the intellectual machinery for understanding their own emotions and the feelings of others.

"One of the brain regions that undergoes this dramatic development during adolescence is the pre-frontal cortex, the part of the front of the brain that makes us human," said Dr Blakemore. "It's involved in all sorts of high-level cognitive functions like making decisions and also understanding other people and social awareness."

Brain scans of teenagers and adults show that as, people get older, they begin to use the pre-frontal cortex at the expense of the superior temporal sulcus, at the back of the brain. "It's as if the pattern of brain activity shifts from the back of the brain to the front of the brain during adolescence to do this kind of empathy task," said Dr Blakemore.

A second study found that the brains of teenagers changed as they grow older in a way that makes them more efficient at seeing things from other people's perspectives. "The studies suggest that it's not just hormones that are causing teenagers to be their typical selves, it could also be the fact that their brains are developing as well," said Dr Blakemore. "Nobody knows whether it's genetically pre-programmed or whether it is influenced by the environment. Possibly there's a bit of both."
http://news.independent.co.uk/world/science_technology/article1372019.ece

he he, I still think mine is improving...

nomad a écrit:

he he, I still think mine is improving...

oui oui.. moi aussi j'ai lu ca et je me suis remplie d'espoir

c'est nous les bizarres alors, pas les Neanterthaliens...


Scientist: Humans Strange, Neanderthals Normal
By Charles Q. Choi
Special to LiveScience
posted: 08 September 2006
12:05 pm ET


Neanderthals are often thought of as the stray branch in the human family tree, but research now suggests the modern human is likely the odd man out.

"What people tend to do is draw a line from our ancestors straight to ourselves, and any group that doesn't seem to fit on that line is divergent, distinct, unusual, strange," researcher Erik Trinkaus, an anthropologist at Washington University in St. Louis, told LiveScience today. "But in terms of evolution of our family tree, the genus Homo, we're the outliers and the Neanderthals are more toward the core."

Humans are not at the inevitable end of a sequence, Trinkaus said. "It just happens that we happen to be alive today and Neanderthals are not."

Trinkaus spent decades examining fossil skeletons and over time realized that maybe researchers looked at Neanderthals the wrong way. Over the last two years, he systematically combed through fossils, comparing Neanderthal and modern human skull, jaw, tooth, arm, leg traits with those of the earliest members of the genus Homo in terms of their shape.

"I wanted to see to what extent Neanderthals are derived, that is distinct, from the ancestral form. I also wanted to see the extent to which modern humans are derived relative to the ancestral form," Trinkaus said.

Trinkaus focused on skeletal features that seemed most strongly linked to genetics, as opposed to any traits that might get influenced by lifestyle, environment or wear and tear.

When compared with our common ancestors, Trinkaus discovered modern humans have roughly twice as many uniquely distinct traits as Neanderthals. In other words, Neanderthals are more like the other members of our family tree than modern humans are.

"In the broader sweep of human evolution, the more unusual group is not Neanderthals, whom we tend to look at as strange, weird and unusual, but it's us, modern humans," Trinkaus said.

Modern humans, for example, are the only members of our family tree who lack brow ridges, Trinkaus said. "We are the only ones who have seriously shortened faces. We are the only ones with very reduced internal nasal cavities. We also have a number of detailed features of the limb skeleton that are unique."

Trinkaus published his findings in the August 2006 issue of the journal Current Anthropology.
http://www.livescience.com/othernews/060908_humans_odd.html

Les chinois ont deja reussi les premiers tests de fusion?????????????

China claims fusion reactor test a success
http://www.msnbc.msn.com/id/15043462/

good !

bon, ça veut dire à terme, que Framatome France ne va bientôt plus leur vendre la technologie du nucléaire à la française, ils l'ont déjà bien assimilée et améliorée !

et peut-être que les seigneurs de guerre islamistes se feront doux comme des agneaux si nous pouvons nous passer de leur pétrole !

nomad a écrit:

good !

bon, ça veut dire à terme, que Framatome France ne va bientôt plus leur vendre la technologie du nucléaire à la française, ils l'ont déjà bien assimilée et améliorée !

oui mais.. nous devions etre les premiers.. tu te rappelle du concours que la France avait gagne pourqu'on construise le grand labo de fusion machin je ne sais pas ou ?? On s'etait battu contre le Japon pour le faire ici .. On etait contents d'avoir gagne et on pensait qu'on allait faire plein de fric! et alors maintenant cela veut dire qu'on est bien en retard Je ne sais pas s'ils ont meme pose la premiere pierre pour construire le batiment en France.. et les chinois sont deja dans des tests?

Citation :

et peut-être que les seigneurs de guerre islamistes se feront doux comme des agneaux si nous pouvons nous passer de leur pétrole !

Ah ben... le probleme c'est que l'on ne peut pas encore
Je veux dire.. question voitures pas probleme... on a deja la technologie.. il suffit d'investir des millions pour tout remplacer... on peut avoir de l'electrique, des hybrides... de l'air comprese.. etc..
mais le probleme c'est les avions... comment on remplace? et les industries....

On a trouve de tissu preservé dans un os de Tyranosaurus Rex!!

http://www.calacademy.org/science_now/headline_science/T-rex_soft_tissue.html

Ole a écrit:

nomad a écrit:

good !

bon, ça veut dire à terme, que Framatome France ne va bientôt plus leur vendre la technologie du nucléaire à la française, ils l'ont déjà bien assimilée et améliorée !

oui mais.. nous devions etre les premiers.. tu te rappelle du concours que la France avait gagne pourqu'on construise le grand labo de fusion machin je ne sais pas ou ?? On s'etait battu contre le Japon pour le faire ici .. On etait contents d'avoir gagne et on pensait qu'on allait faire plein de fric! et alors maintenant cela veut dire qu'on est bien en retard Je ne sais pas s'ils ont meme pose la premiere pierre pour construire le batiment en France.. et les chinois sont deja dans des tests?

Citation :

et peut-être que les seigneurs de guerre islamistes se feront doux comme des agneaux si nous pouvons nous passer de leur pétrole !

Ah ben... le probleme c'est que l'on ne peut pas encore
Je veux dire.. question voitures pas probleme... on a deja la technologie.. il suffit d'investir des millions pour tout remplacer... on peut avoir de l'electrique, des hybrides... de l'air comprese.. etc..
mais le probleme c'est les avions... comment on remplace? et les industries....

je croyais que nous l'avions également testé en laboratoire !

ben oui, pour les avions, ou ça va devenir un luxe de voyager en avion, ou faudra faire autrement qu'avec le kerozène, et l'hydrogène, c'était pas dans les fusées de "tintin" ?

nomad a écrit:

je croyais que nous l'avions également testé en laboratoire !

euh... maintenant que tu le dis comme ca... je me dis qu'avant la creation de la plante a fusion peut etre qu'on a teste non? car ce qu'on va construire c'est deja la plante et pas juste un labo.. n'est ce pas? (je suis un peu perdue avec tout ca...)

Citation :

ben oui, pour les avions, ou ça va devenir un luxe de voyager en avion, ou faudra faire autrement qu'avec le kerozène, et l'hydrogène, c'était pas dans les fusées de "tintin" ?

En star trek ils marchent avec des trucs de plasma...