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Having low levels of vitamin B12 in the blood can be an indicator of risk to suffer brain atrophy. This suggests a new study by U.S. researchers, who presented showing that these deficiencies were lower on cognitive tests and were found to have less total brain volume.
(Those with deficiencies of vitamin B12 in the blood were found to have less brain volume. Photo: Tom Haex.)
“Vitamin B12 deficiency is a potential risk factor for brain atrophy and may contribute to cognitive impairment,” said Christine C. Tangney, author of the study conducted by researchers at Rush University Medical Center in Chicago (USA) and published in the journal Neurology .
The analysis of results obtained from older people, who had concluded that deficiencies of vitamin B12 in their blood scored lower on cognitive tests and were found to have less total brain volume. “A British team has done another study using vitamin B which has obtained data that support these results” confirms Tangney.
The study involved 121 people over the south side of Chicago who, for 4 ½ years, underwent several blood tests to identify changes in their levels of vitamin B12. They were also tested to measure their memory and cognitive ability. At the end of the process, MRIs were performed on patients to assess the state of his brain and brain volume.
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The anxiety would arise in microscopic connections linking two tiny areas of the brain.
According to a study by the Institute for Public Health conducted among 36,000 people from 1999 to 2003, 17 percent of men and 25 percent of women suffer from anxiety disorders, either generalized anxiety, agoraphobia, social phobia, panic disorder and posttraumatic stress disorder.
But whence comes the anxiety? Somehow it pops out of nowhere, since it is defined as a state of apprehension or fear domestic unrelated to a real danger. A recent study from Stanford University in California, connections between two tiny brain centers regulate the level of anxiety. These two control centers belong to a cerebral structure considered as a pivot of emotions: the amygdala brain. One, the basolateral amygdala, sends projections or axons, which activates its partner, the amygdala centrolaterale.
These connections have been examined by a method optogenetics: these cables are introduced into neural photosensitive protein, which triggers electrical currents in the axons when exposed to light. An optical fiber enters the brain of the animal and illuminates the tip of axons, where neurons in the basolateral amygdala are in contact with those of the amygdala centrolaterale.
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This hormone produced in quantity by the mother at birth increase the resistance of newborn pain.
The child suffers there at birth? Just after her birth, the newborn is less sensitive to pain if born vaginally if it is born by caesarean section showed a Swedish team in 2008. A group of neurobiologists French, Finnish, Russian and Italian team led by R. Khazipov and Y. Ben-Ari, Institute of Neurobiology of the Mediterranean (Inserm / Université de la Méditerranée) in Marseille, just highlight the mechanism that protects the child from the pain at birth and for a few hours later.
Birth is stressful for the child, or even pain when the fetus is compressed or lack of oxygen, or when the use of forceps. In 2008, the Swedish team had observed that children who were born by natural means less responsive to painful stimuli than those born by Caesarean section, suggesting that a mechanism had been activated pain during childbirth and remained effective for several hours.
During childbirth, the production of oxytocin in the mother increases significantly: this hormone promotes the contraction of the uterus, breast feeding and attachment to the newborn, and adult, she has a particular analgesic effect. In previous work, the Marseille team had shown that oxytocin inhibits neurons in the cortex of fetal rats by changing the concentration of chloride ions they contain.
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Can we never be afraid? A woman is living proof.
Unique in the annals of neurology, a woman aged 44, designated by the initials SM, suffers from a teenager to a destruction of an area of the brain (the amygdala) due to a rare genetic disorder, called Urbach-Wiethe. She is currently the only person who does this brain structure essential to a sense of fear. Its behavior is shown.
Neuropsychologists Antonio Damasio, Justin Feinstein, Daniel Tranel and colleagues from the Univer-sity of Iowa, showed that this woman is never afraid of anything. They were taken to a animal that has been approaching the most dangerous snakes: she played with the tip of their tongue or scrape the scales. When she tried to catch a tarantula, it was necessary to retain power because she was unconscious of danger. Waverly Hills Sanatorium to conduct a dreary building where approximately 60 000 TB patients died in the early twentieth century, considered the most sinister place of America and now converted into a park feel, she was the only person in the group of visitors Do not yell at the turning lanes, and wish to discuss with monsters …
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Research shows that it is possible to grow neurites of nerve cells in thin nanotubes in semiconductor material based on silicon and germanium
Create an embryonic neural circuit-e by growing the extensions of nerve cells in thin nanotubes in semiconductor material based on silicon and germanium: the company has succeeded to a group of researchers from the University of Wisconsin at Madison conducted by Minrui Yu, illustrates that the an article (“Semiconductor Nanomembrane Tubes: Three-Dimensional Confinement for Controlled neuritis outgrowth”) published in the journal ACS Nano.
The hope of this kind of research is the ability to be able to put a chip in connection with specific groups of cells to re-establish connections that were interrupted. So far, attempts at integration between artificial neurons and circuits was experienced with the use microrlettrodi places in connection with the membranes of cells, a procedure but in the long run may result in damage to the nerve cell.
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Specific brain regions are activated in the masters of Japanese chess when they play, making the choice of next move almost automatically.
Shogi, or Japanese chess, is a board game popular in Japan. Like chess professionals, masters of shogi play three to four hours per day. Unlike the amateur or casual gamers, they claim to feel the best move to play intuitively. X. Wan, Institute of RIKEN Brain Science in Wako, Japan, and colleagues have shown that the ability of experts of shogi is due to activation of specific brain regions when they play.
We know that the great masters of shogi or chess recognize immediately, in less than a second, clusters of a few familiar pieces corresponding to configurations known, probable and logical, with a particular meaning in their knowledge of the game These groupings, appointed chunksParticipate in the organization of long-term memory. In chess, a player must store in memory between 50 000 and 300 000 chunks to reach the expert level. These groupings will not only memorized the player to produce configurations quickly, but also to find the best move to play automatically.
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Local anesthesia alters the perception of the body by the patient: for example it has the impression that the member has doubled in volume asleep or he is not in his place.
“Did it hurt when I? “That’s the question you probably ask the doctor when anesthetizing a region of your body if you answer yes, this means that anesthesia is not effective (the nerves in this region are still sending information to the brain), otherwise, is that this part of the body is asleep and you do not “feel” more. But the bodily sensation under anesthesia is more complicated than it seems: Stein Silva, Inserm Unit 825 “Brain imaging and neurological disability” at the University Paul Sabatier in Toulouse, and colleagues have shown that local anesthesia disrupts not only the tactile sensations that the patient’s body, but also his visual perception.
Pain and more generally all bodily sensations are mental events in which the brain is the physical medium. Representations of the body by the brain are necessary for self-awareness to control his movements, to recognize others, etc.. But the sense of self seems altered at a regional anesthesia that numbs a “territory” of the body connected to one or more nerves. Indeed, when such interventions, patients often report they feel that the region of sleeping their bodies swell, change size or is not in the position where it actually is.
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Neurobiologists have identified the neural circuits involved in fear learning and behavioral expression.
The frightened man begins to freeze like a statue, motionless and breathless, or crouches as instinctively to escape the gaze of others. The heart beats violently, and throbs or beats against the shore … The hairs on the skin stand, and the superficial muscles shiver. Because of the change in heart rate, respiration is accelerated … The mouth becomes dry and is often opened and closed.
Charles Darwin, The Expression of Emotions in Man and Animals.
One senses the fear in the presence or the prospect of danger. The physiological manifestations that accompany it, such as increased heart rate, the staring eyes, or the creepy, are due to release a hormone, adrenaline. These physiological changes can react quickly: the subject in danger prepares to flee or fight, thus ensuring his survival. However, some people suffer from exaggerated manifestations of fear such subjects quote drops till phobia, a posttraumatic stress disorder or anxiety disorders. They have abnormalities of certain neural circuits involved in fear, which causes anxiety reactions inadequate. But what are these channels?
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A search of the University Concordia Montreal the link between hormones, attention and learning.
Lack of energy and trouble concentrating? The fault could be hormone based on the results of new research from Concordia University published in the journal Brain and Cognition. This study shows that high levels of estrogen are associated with attention deficit disorder and learning. This is the first article to explain how these disorders can be attributed to the direct effect of hormones on brain structures mature.
“Even if we know that estrogen plays an important role in learning and memory, this is far from consensus,” said Wayne Brake, assistant professor in the Center for Studies in Behavioral Neurobiology at Concordia University and lead author of the study. Thanks to a well-established model of learning called latent inhibition, our results show unequivocally that high levels of estrogen inhibit cognition in female rodents. ”
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The identification of NOX4 as an enzyme has a key role in neuronal death following a stroke, opens the door to a promising therapy for this disease
The inhibition of NOX4 , which has a central role in the cellular production of hydrogen peroxide , can be the key to greatly reduce the damage caused by a stroke. And ‘ this is the result of research conducted at the University of Maastricht and Würzburg – which is reported in an article published in PLoS Biology - which has been administered a substance that inhibits that enzyme and found that the brain damage resulting from a stroke were significantly reduced even when it was administered at a distance of hours after the event .
Hydrogen peroxide – a common hydrogen peroxide – is one of substances the most active produced during inflammatory reactions mainly by macrophages to ” sterilize ” the site where occurs an injury and to eliminate pathogens and damaged cells. Much of the damage resulting from stroke are not , of course, due to the event itself but the excessive reaction of the body.
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(Those with deficiencies of vitamin B12 in the blood were found to have less brain volume. Photo: Tom Haex.)
According to a study by the Institute for Public Health conducted among 36,000 people from 1999 to 2003, 17 percent of men and 25 percent of women suffer from anxiety disorders, either generalized anxiety, agoraphobia, social phobia, panic disorder and posttraumatic stress disorder.
The child suffers there at birth? Just after her birth, the newborn is less sensitive to pain if born vaginally if it is born by caesarean section showed a Swedish team in 2008. A group of neurobiologists French, Finnish, Russian and Italian team led by R. Khazipov and Y. Ben-Ari, Institute of Neurobiology of the Mediterranean (Inserm / Université de la Méditerranée) in Marseille, just highlight the mechanism that protects the child from the pain at birth and for a few hours later.
Shogi, or Japanese chess, is a board game popular in Japan. Like chess professionals, masters of shogi play three to four hours per day. Unlike the amateur or casual gamers, they claim to feel the best move to play intuitively. X. Wan, Institute of RIKEN Brain Science in Wako, Japan, and colleagues have shown that the ability of experts of shogi is due to activation of specific brain regions when they play.
“Did it hurt when I? “That’s the question you probably ask the doctor when anesthetizing a region of your body if you answer yes, this means that anesthesia is not effective (the nerves in this region are still sending information to the brain), otherwise, is that this part of the body is asleep and you do not “feel” more. But the bodily sensation under anesthesia is more complicated than it seems: Stein Silva, Inserm Unit 825 “Brain imaging and neurological disability” at the University Paul Sabatier in Toulouse, and colleagues have shown that local anesthesia disrupts not only the tactile sensations that the patient’s body, but also his visual perception.
The frightened man begins to freeze like a statue, motionless and breathless, or crouches as instinctively to escape the gaze of others. The heart beats violently, and throbs or beats against the shore … The hairs on the skin stand, and the superficial muscles shiver. Because of the change in heart rate, respiration is accelerated … The mouth becomes dry and is often opened and closed.