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Friday, December 23, 2011

Myths and Truths of Obesity and Pregnancy



 by  

Ironically, despite excessive caloric intake, many obese women are deficient in vitamins vital to a healthy pregnancy. This and other startling statistics abound when obesity and pregnancy collide. Together, they present a unique set of challenges that women and their doctors must tackle in order to achieve the best possible outcome for mom and baby.
In the December issue of the journal Seminars in Perinatology, maternal fetal medicine expert Loralei L. Thornburg, M.D., reviews many of the pregnancy-related changes and obstacles obese women may face before giving birth. The following myths and truths highlight some expected and some surprising issues to take into account before, during and after pregnancy.
“I treat obese patients all the time, and while everything may not go exactly as they’d planned, they can have healthy pregnancies,” said Thornburg, who specializes in the care of high-risk pregnancies and conducts research on obesity and pregnancy. “While you can have a successful pregnancy at any size, women need to understand the challenges that their weight will create and be a partner in their own care; they need to talk with their doctors about the best way to optimize their health and the health of their baby.”

Myth or Truth?
Many obese women are vitamin deficient.
True
Forty percent are deficient in iron, 24 percent in folic acid and 4 percent in B12. This is a concern because certain vitamins, like folic acid, are very important before conception, lowering the risk of cardiac problems and spinal defects in newborns. Other vitamins, such as calcium and iron, are needed throughout pregnancy to help babies grow.
Thornburg says vitamin deficiency has to do with the quality of the diet, not the quantity. Obese women tend to stray away from fortified cereals, fruits and vegetables, and eat more processed foods that are high in calories but low in nutritional value.
“Just like everybody else, women considering pregnancy or currently pregnant should get a healthy mix of fruits and vegetables, lean proteins and good quality carbohydrates. Unfortunately, these are not the foods people lean towards when they overeat,” noted Thornburg. “Women also need to be sure they are taking vitamins containing folic acid before and during pregnancy.”
Obese patients need to gain at least 15 pounds during pregnancy.
Myth
In 2009, the Institute of Medicine revised its recommendations for gestational weight gain for obese women from “at least 15 pounds” to “11-20 pounds.” According to past research, obese women with excessive weight gain during pregnancy have a very high risk of complications, including indicated preterm birth, cesarean delivery, failed labor induction, large-for-gestational-age infants and infants with low blood sugar.
If a woman starts her pregnancy overweight or obese, not gaining a lot of weight can actually improve the likelihood of a healthy pregnancy, Thornburg points out. Talking with your doctor about appropriate weight gain for your pregnancy is key, she says.
The risk of spontaneous preterm birth is higher in obese than non-obese women.
Myth
Obese women have a greater likelihood of indicated preterm birth – early delivery for a medical reason, such as maternal diabetes or high blood pressure. But, paradoxically, the risk of spontaneous preterm birth – when a woman goes into labor for an unknown reason – is actually 20 percent lower in obese than non-obese women. There is no established explanation for why this is the case, but Thornburg says current thinking suggests that this is probably related to hormone changes in obese women that may decrease the risk of spontaneous preterm birth.
Respiratory disease in obesity – including asthma and obstructive sleep apnea – increases the risk for non-pulmonary pregnancy complications, such as cesarean delivery and preeclampsia (high blood pressure).
True
Obese women have increased rates of respiratory complications, and up to 30 percent experience an exacerbation of their asthma during pregnancy, a risk almost one-and-a-half times more than non-obese women. According to Thornburg, respiratory complications represent just one piece of the puzzle that adds to poor health in obesity, which increases the likelihood of problems in pregnancy. She stresses the importance of getting asthma and any other respiratory conditions under control before getting pregnant.
Breastfeeding rates are high among obese women.
Myth
Breastfeeding rates are poor among obese women, with only 80 percent initiating and less than 50 percent continuing beyond six months, even though it is associated with less postpartum weight retention and should be encouraged as it benefits the health of mom and baby.
Thornburg acknowledges that it can be challenging for obese women to breast feed. It often takes longer for their milk to come in and they can have lower production (breast size has nothing to do with the amount of milk produced). Indicated preterm birth can result in prolonged separations of mom and baby as infants are admitted to the neonatal intensive care unit or NICU. This, coupled with the higher rate of maternal complications and cesarean delivery – up to 50 percent in some studies – in obese women, can make it harder to successfully breast feed.
“Because of these challenges, mothers need to be educated, motivated and work with their doctors, nurses and lactation professionals to give breast feeding their best shot. Even if you can only do partial breastfeeding, that is still better than no breastfeeding at all,” said Thornburg.
______________
Courtesy  University of Rochester Medical Center

Jab Teri Aarti Gatey Shirdi Sai Baba New Song 2011

                         Jab Teri Aarti Gatey a biggest Devotional hit from Sai Special Album - Aana Sai Dham Singer of This Spiritual Track - Sinu Nigam & Music By - Rahul Srivastav. Penned by (Lyricist) - Arsh Amritsari. Aana Sai Dham has been rated as one of the biggest and rare devotional hits in thebhaktisagar. The track Jab Teri Aarti Gatey has broken all records across platforms & has helped in giving hindi religious music greater heightes. It is being sung by the one of the famous singers Sinu Nigam. Subscribe Here For More Updates & See Latest Videos

Thursday, December 22, 2011

Are you care about the Environment??


HARD DISK drive with 5 MB of storage...!! 1956



This Picture was Taken in 1956.

That's a HARD DISK drive with 5 MB of storage...!!

In September 
1956 , IBM launched the 305 RAMAC, the first 'SUPER' computer with a hard disk drive (HDD). The HDD weighed over a ton and stored 5 MB of data.

The Right Use of Energy


 


Krishna's lotus feet“The expert electrician can utilize the electrical energy for both heating and cooling by adjustment only. Similarly, the external energy, which now bewilders the living being into continuation of birth and death, is turned into internal potency by the will of the Lord to lead the living being to eternal life.” (Shrila Prabhupada, Shrimad Bhagavatam, 1.3.34 Purport)
Energy is in full force throughout the environment. More than just the electrical socket capable of powering appliances and electronic gadgets, the powerful energy pervading every inch of space can be put to use to further many specific ends. The individual objects of this energy include the very bodily coverings of the jivas, the spirit souls wandering through a cycle of birth and death that perpetually spins. Those who know how to make proper use of the energy receive the full benefits that an existence has to offer. Through proper utilization, the same energy that was previously inhibiting becomes enlightening by the grace of the person from whom it came.
Birth and death really take place at every second? Think of your hair and nails growing and then getting cut off. Think of the dead skin cells that the body sheds every single day. Think of how your body is different now from the way it was just the day before. Through preoccupation with other tasks, these subtle changes go unnoticed, but to someone who doesn’t see you every day, the shifts are noticeable the next time they take a look at you. On a larger scale, the daytime gradually shifts into nighttime, but this change isn’t noticed as easily if we are staring at the sky the entire day. As the expression goes, “like watching paint dry”, the gross material elements take a while to morph and form new shapes, but through the effects of time and the operation of the superior energy, these shifts take place nonetheless.
“Besides this inferior nature, O mighty-armed Arjuna, there is a superior energy of Mine, which are all living entities who are struggling with material nature and are sustaining the universe.” (Lord Krishna
 
Bhagavad-gita
 
, 7.5)
Krishna's lotus feetSpirit is the superior energy. Matter is incapable of autonomous movement. Without a vital force within the body, the previously utilized hands, legs and feet start to rot and decay. Just any old collection of matter doesn’t grow into a viable living entity. There must first be a spiritual injection. Even the larger collections of matter, such as the mountains, rivers and clouds, are beholden to the wind and the nature that controls it. There is spirit inside each of these bodies instigating their movements; therefore the spiritual energy is considered superior.
Just how to make proper use of the external energy is what bewilders the innumerable sparks belonging to the superior energy. If an energetic force is superior then how can it be bewildered? The susceptibility to bewilderment explains the marginal position of the jiva with respect to the different energies coming from the Supreme Lord, who is known as Shri Krishna in the Vedic tradition. Not that Krishna is a mythological character or a folk hero of the Hindus; He is the very same Supreme Lord for all of humanity but with His features more clearly defined. The Vedas are so nice that they don’t just espouse a sectarian belief, with others compelled to convert to their way based on dogmatic insistence. The Vedas are the supreme science, as in the mundane scientific world there is politics and even consensus, as has been recently introduced with specific theories that others are reluctant to subscribe to.
 
 in the Vedas is presented as the science of self-realization, something that operates on every living entity, not just the human being. One person may identify themselves as Christian, another as Jewish, and another as Hindu
 
, but one who actually studies self-realization identifies as spirit soul, aham brahmasmi. The spirit soul is superior to matter, and it is trapped in a cycle of reincarnation
 
for a reason. There is a superior spirit soul, a singular entity from whom the different sparks emanated. Think of a giant fire that gives off sparks but at the same time doesn’t lose any of its intensity. The only thing we know that bears this property is the sun, which continuously beams off heat and light and yet doesn’t require an external fuel source. As part of the material creation, the sun had an inception date and thus will also have a date of destruction. Krishna is the supreme spiritual sun, so He is never bereft of His qualities. He transcends the bounds of time and space, a feature incomprehensible to the human being limited by their material brainpower.
Krishna's fluteIf Krishna is beyond our thinking, why the need for self-realization? Why even discuss the different energies? Why not just live? The path of least resistance is taken by default, but the living entity still has something driving their behavior. In addition to the presence of instigation, there are multiple avenues taken; the activities aren’t always the same. As the search for ananda, or bliss, is the common catalyst, the discipline of self-realization is provided to allow for everyone to find that ananda. If we are more familiar with our properties and our position in the grand scheme of things, we will be better able to attain real bliss, without wasting time in fruitless ventures.
The pursuits of the spirit souls wandering through the material world without any guidance in spiritual matters can be compared to the animal rummaging the forest looking for food. One animal looks in one direction, while another takes their own route. Some eat more than others, while some decide to kill other animals for food. Irrespective of the avenue taken, the search for food will continue, as the enjoyment from eating is short-lived. The self-realized soul is one who finds their enjoyment both internally and externally, an art form they learned from following a bona fide discipline of spirituality, one which addresses the different energies, its source, and how to connect with it. The fountainhead of bliss and knowledge gives the proper information to those who wish to connect with Him in a mood of love.
What is at the core of this discipline? For starters, when the proper identification as spirit soul is there, the world can be viewed correctly instead of incorrectly. Immediately, sectarian, racial, national, gender, and even species boundaries are eliminated. The humble soul learning self-realization understands that there is no difference between a cat, dog, monkey, human being, ant, man, and woman. Every form of life is equal at the constitutional level, though we may show different outward treatment. Not everyone will be self-realized. A tiger doesn’t even know that it’s a tiger, so how can we expect it to treat us peacefully or under rational thought?
“The humble sage, by virtue of true knowledge, sees with equal vision a learned and gentle brahmana, a cow, an elephant, a dog and a dog-eater [outcaste] .” (Lord Krishna, Bg. 5.18)
Krishna with cow and birdsThe equal vision of the spiritualist is there initially for their own benefit. Knowing that we are spirit helps us understand that the matter around us is not meant for our association. Does this mean that we should give up all sensual pursuits, disengage from the senses? If I know that my car is not part of my identity, do I just abandon it? Do I sell the car immediately and never drive it again? This path of self-realization seems tempting, and it does have the benefit of bringing less entanglement in daily affairs, but there are some flaws.
The material energy is there for a reason. It is harmful when it is used for identification purposes, but it can prove beneficial for one who finds the proper engagement in life. Glorification of the Supreme Lord under the yoga discipline of bhakti is the constitutional occupation of the spirit soul, who is similar in quality to Krishna but vastly inferior in quantitative possession of divine attributes. Krishna is meant to be served and the spirit souls are meant to do the serving. Whether we like this fact or not is irrelevant; it is the natural order of things. The brilliance of the natural order is that anyone who follows it finds supreme pleasure, so much so that Krishna Himself is unable to stop their outpouring of emotion. In no other endeavor is this kind of love established, as the material world checks everyone’s service through the influence of time and space.
 
 in its highest form continues unmotivated and uninterrupted, life after life, in whatever body type the living entity may find. Reincarnation is already there with our present birth; we just have a little difficulty accepting the fact that it will continue into the afterlife. The transmigration of the soul shouldn’t be so difficult to understand, as there was spiritual action that caused our present birth. We also know that spiritual action continues after someone dies, so why should we deny that there is both a past and future life?
“Whatever state of being one remembers when he quits his body, that state he will attain without fail.” (Lord Krishna, Bg. 8.6)
Krishna's fluteReincarnation flows in the direction of the consciousness of the living entity. The jiva is in the marginal position, so he can choose in favor of Krishna’s association or surrender to maya, the material energy. Association with maya brings temporary ups and downs that fluctuate like the stock market. At the time of death, one body type is renounced in favor of another, with the cycle of birth to death then repeated. This continues for as long as the material nature is used improperly. As soon as there is a proper identification of the different energies and its original source, bhakti-yoga can be adopted with the utmost sincerity.
Under bhakti, the same material energy that was previously inhibiting becomes the source of enlightenment, pleasure, anticipation, and unending opportunities for service. The example often cited by His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
 
, the greatest champion and exponent of devotional service in modern times, was to the electricity that is available in a house. The same electricity can be used for both heating and cooling, which means that the electricity is not partial. In the same way, the material energy doesn’t have to be inhibiting. It doesn’t have to be the cause of perpetual bondage in a land divorced of God’s personal presence.
If someone were to hand us a laptop computer, the person identifying with matter and its objects may become ecstatic and use the machine for their own sense gratification. Surf the internet, listen to music, chat with their friends, basically do anything that is considered “fun”. The person who has renounced material interaction will be disappointed in receiving the same gift. To them the laptop is a brick that is heavy and causes an unnecessary burden to the person carrying it around. The owner also needs to learn how to use it, make sure that it is maintained, and pay for the electricity that goes into its operation.
The bhakta, however, neither identifies with the laptop nor despises it. Rather, every aspect of the material energy is used for connecting with Krishna. Even if something is renounced, that object becomes purified because at least it was used in an evaluation that eventually conjured up the image of Shyamasundara
 
 within the mind. Any time the consciousness can evoke Krishna’s image - where He is holding His flute, wearing a peacock feather in His hair, smiling so sweetly, enticing the spirit soul to come back to His spiritual home of Goloka Vrindavana
 
 - there is progress made towards finding lasting ananda.
Krishna photo galleryIf the devotee can, they will use the laptop to store pictures of Krishna and His many expansions. They will get the many books authored by the Vaishnava saints and place them on the device to read. They will use the keyboard and word processing programs to daily glorify their beloved Krishna and explain the flawless science of self-realization to others. In this way, both the materialist and dry renouncer missed out on a wonderful opportunity with the gift of the laptop.
The gross collection of material elements affords every single one of us the same opportunities. A sparse place lacking an influx of people and modern amenities can be enjoyed by those looking for peace and simultaneously despised by those looking for many activities involving material interaction. But if the same area has temples dedicated to the Lord, where His glories are constantly sung, such as through the sacred sound vibration of the maha-mantra, “Hare Krishna Hare Krishna, Krishna Krishna, Hare Hare, Hare Rama Hare Rama, Rama Rama, Hare Hare
 
”, then saintly people will congregate there. With the presence of the saints the place turns into a pilgrimage site, an area where self-realization flourishes through both the existence of spiritual houses of worship and the association of devoted men.
The aim in this life is to use everything around us for kirtana, or glorification of the Supreme Lord, the person who provides happiness to anyone who connects with Him in a mood of love and devotion. The search for ananda will continue despite one’s awareness of the self, but only in the discipline of bhakti can the sweetest tasting fruit to our existence be found. The quality of the benefit is what determines the worthiness of the activity. As Krishna’s association is the unmatched jewel of a reward, the ancient art of bhakti, or divine love, becomes the only worthy engagement in life.
In Closing:
Electricity runs through the house,
Gives heat for both children and spouse.
Same force that is responsible for heating,
In summer operates machines for cooling.
Material nature also in neutrality,
Provides items to maintain being’s vitality.
Use nature the wrong way and you’ll be bound,
To cycle of birth and death, no bliss found.
But if you use matter to connect with Krishna,
You’ll taste sweet fruit of life, endless ananda.

FULFILL YOUR POTENTIAL AND ACCOMPLISH YOUR 2012 GOALS




How to set a Goal, and How to Reach it

This time of year, goal-setting becomes a bit of a cliche. That’s because we’re doing it wrong. How our goals can help us learn who we are, and what we’re capable of.

By René Shimada Siegel 
Gifts wrapped? Check. Waistband? A little too tight. Harmony at home? Well… Business running like clockwork? No? Time for New Year’s resolutions!
Why bother? Why reinforce the cliché — make a resolution and then go ahead and break it? I do it because I know setting goals is the secret to progress.
Resolutions aren’t destinations. They’re starting points. We may never reach our destination or goal, and even if we do, we may discover it isn’t where we really want to be. Goals help us figure out what we think we want, but more importantly, goals help us figure out who we are and what we’re capable of achieving.
There is no right or wrong way to do this, but here are four things I always keep in mind when making my New Year’s resolutions:
Stretch, but not too far. My yoga teacher always tells the new students, “Take it easy. If you wake up sore tomorrow morning, you’ll blame me and not come back and we’ll both be disappointed.” On the other hand, meeting too-easy goals is unfulfilling. Set stretch goals, just don’t reach so far that you won’t take them seriously.
Consider the power of three. One coach I work with suggests resolutions that consist of three words. I like this a lot. It’s more loosely defined than one ominous goal. Select three concepts that will bring positive change in varying degrees throughout the year. Fun. Power. Attitude. Fit. Courage. Listen. Give. Post your three words everywhere as reminders to make decisions that reinforce your positive concepts—not in terms of pounds lost, dollars made or quantum shifts achieved.
Be an exhibitionist. In addition to reminder Post-It Notes on my mirror and computer, setting goals and working on them in public has two benefits. It makes me more accountable and can be a source of strength. A friend recently created a Facebook group called “Just Stick With It” to support her effort to become physically fit. It’s become a great motivator and confessional for 21 busy women. Suddenly we’re accountable to someone else, with our goals and integrity at stake. If we all hadn’t shared our fitness and weight loss goals, we wouldn’t be receiving this support. So live your life out loud.
Continue reading this article at INC.com

How do we split our attention?



McGill's Cognitive Neurophysiology Lab team finds that we are natural-born multi-taskers.
Imagine you're a hockey goalie, and two opposing players are breaking in alone on you, passing the puck back and forth. You're aware of the linesman skating in on your left, but pay him no mind. Your focus is on the puck and the two approaching players. As the action unfolds, how is your brain processing this intense moment of "multi-tasking"? Are you splitting your focus of attention into multiple "spotlights?" Are you using one "spotlight" and switching between objects very quickly? Or are you "zooming out" the spotlight and taking it all in at once?
These are the questions Julio Martinez-Trujillo, a cognitive neurophysiology specialist from McGill University, and his team set out to answer in a new study on multifocal attention. They found that, for the first time, there's evidence that we can pay attention to more than one thing at a time.
"When we multi-task and attend to multiple objects, our visual attention has been classically described as a "zoom lens" that extend over a region of space or as a spotlight that switches from one object to the other," Martinez-Trujillo, the lead author of the study, explained. "These modes of action of attention are problematic because when zooming out attention over an entire region we include objects of interest but also distracters in between. Thus, we waste processing resources on irrelevant distracting information. And when a single spotlight jumps from one object to another, there is a limit to how fast that could go and how can the brain accommodate such a rapid switch. Importantly, if we accept that attention works as a single spotlight we may also accept that the brain has evolved to pay attention to one thing at the time and therefore multi-tasking is not an ability that naturally fits our brain architecture"
Martinez-Trujillo's approach in getting to the bottom of this long-standing controversy was novel. The team recorded the activity of single neurons in the brains of two monkeys while the animals concentrated on two objects that circumvented a third 'distracter' object. The neural recordings showed that attention can in fact, be split into two "spotlights" corresponding to the relevant objects and excluding the in-between distracter.
"One implication of these findings is that our brain has evolved to attend to more than one object in parallel, and therefore to multi-task," said Martinez-Trujillo. "Though there are limits, our brains have this ability."
The researchers also found that the split of the "spotlight" is much more efficient when the distractors are very different from the objects being attended. Going back to the very apt hockey analogy, Martinez-Trujillo explained that if a Montreal Canadiens forward is paying attention to two Boston Bruins in yellow and black, he'll have a more difficult time ignoring the linesmen, also wearing black, than if he was in a similar situation but facing two Vancouver Canucks with blue and green uniforms, easily distinguishable from the linesmen in black'.
In the next generation of experiments, the researchers will explore the limits of our ability to split attention and multi-task – looking more closely at how the similarity between objects affects multi-tasking limits and how those variables can be integrated into a quantitative model.
This study was published this week in the journal Neuron.
Provided by McGill University
"How do we split our attention?." December 21st, 2011. http://medicalxpress.com/news/2011-12-attention.html
 

Posted by
Robert Karl Stonjek

Listen up: Abnormality in auditory processing underlies dyslexia




People with dyslexia often struggle with the ability to accurately decode and identify what they read. Although disrupted processing of speech sounds has been implicated in the underlying pathology of dyslexia, the basis of this disruption and how it interferes with reading comprehension has not been fully explained. Now, new research published by Cell Press in the December 22 issue of the journal Neuron finds that a specific abnormality in the processing of auditory signals accounts for the main symptoms of dyslexia.
"It is widely agreed that for a majority of dyslexic children, the main cause is related to a deficit in the processing of speech sounds," explains senior study author, Dr. Anne-Lise Giraud and Franck Ramus from the Ecole Normale Supérieure in Paris, France. "It is also well established that there are three main symptoms of this deficit: difficulty paying attention to individual speech sounds, a limited ability to repeat a list of pseudowords or numbers, and a slow performance when asked to name a series of pictures, colors, or numbers as quickly as possible. However, the underlying basis of these symptoms has not been elucidated."
Dr. Giraud and colleagues examined whether an abnormality in the early steps of auditory processing in the brain, called "sampling," is linked with dyslexia by focusing on the idea that an anomaly in the initial processing of phonemes, the smallest units of sound that can be used to make a word, might have a direct impact on the processing of speech.
The researchers found that typical brain processing of auditory rhythms associated with phonemes was disrupted in the left auditory cortex of dyslexics and that this deficit correlated with measures of speech sound processing. Further, dyslexics exhibited an enhanced response to high-frequency rhythms that indirectly interfered with verbal memory. It is possible that this "oversampling" might result in a distortion of the representation of speech sounds.
"Our results suggest that the left auditory cortex of dyslexic people may be less responsive to modulations at very specific frequencies that are optimal for analysis of speech sounds and overly responsive to higher frequencies, which is potentially detrimental to their verbal short-term memory abilities," concludes Dr. Giraud. "Taken together, our data suggest that the auditory cortex of dyslexic individuals is less fine-tuned to the specific needs of speech processing."
Provided by Cell Press
"Listen up: Abnormality in auditory processing underlies dyslexia." December 21st, 2011. http://medicalxpress.com/news/2011-12-abnormality-auditory-underlies-dyslexia.html
 

Posted by
Robert Karl Stonjek

Why bigger is better when it comes to our brain and memory




The hippocampus is an important brain structure for recollection memory, the type of memory we use for detailed reliving of past events. Now, new research published by Cell Press in the December 22 issue of the journal Neuron reveals characteristics of the human hippocampus that allow scientists to use anatomical brain scans to form predictions about an individual's recollection ability. The new research helps to explain why this relationship has been hard to find in the past and provides evidence for a possible underlying mechanism.
The hippocampus, a deep brain structure named for its curving seahorse shape, can be divided into anterior and posterior portions. Although research has generally linked smaller hippocampi with worse recollection in neuropsychological patients and during aging, this relationship has not held up among healthy young adults. "There is some evidence that extensive spatial memory acquisition leads to enlargement of the posterior hippocampus and a decrease in the anterior hippocampus," explains lead study author, Dr. Jordan Poppenk who conducted the study at Baycrest's Rotman Research Institute. "This suggested to us that the crucial predictor of individual differences in recollection ability might not be the overall size of the hippocampus but the separate contributions of the posterior and anterior segments of the hippocampus."
Dr. Poppenk and coauthor Dr. Morris Moscovitch analyzed high-resolution magnetic resonance imaging brain scans of healthy adults who had participated in recollection memory tests. Better recollection was associated with a larger posterior hippocampus and a smaller anterior hippocampus. The overall size of the hippocampus did not predict recollection, as larger posterior hippocampi were offset by smaller anterior hippocampi. The researchers went on to show that the link between the posterior hippocampus and recollection depended on interactions with other parts of the brain between the times that memories were learned and retrieved, particularly regions involved in perception which form the basis of recollected experience.
"Our results show for the first time that the size of the posterior hippocampus, especially when expressed as a ratio to the size of the anterior hippocampus, reliably predicts recollection in healthy adults. This finding explains the longstanding failure to correlate the overall size of the hippocampus with memory," concludes Dr. Poppenk. "We also provide evidence that it is the functional connections, possibly related to memory consolidation, between the posterior hippocampus and other parts of the brain that may underlie enhanced memory recollection."
Provided by Cell Press
"Why bigger is better when it comes to our brain and memory." December 21st, 2011. http://medicalxpress.com/news/2011-12-bigger-brain-memory.html
 

Posted by
Robert Karl Stonjek

How pregnancy changes a woman's brain



(Medical Xpress) -- We know a lot about the links between a pregnant mother’s health, behavior, and moods and her baby’s cognitive and psychological development once it is born. But how does pregnancy change a mother’s brain? “Pregnancy is a critical period for central nervous system development in mothers,” says psychologist Laura M. Glynn of Chapman University. “Yet we know virtually nothing about it.” Glynn and her colleague Curt A. Sandman, of University of the California Irvine, are doing something about that. Their review of the literature in Current Directions in Psychological Science, a journal published by the Association for Psychological Science, discusses the theories and findings that are starting to fill what Glynn calls “a significant gap in our understanding of this critical stage of most women’s lives.”
At no other time in a woman’s life does she experience such massive hormonal fluctuations as during pregnancy. Research suggests that the reproductive hormones may ready a woman’s brain for the demands of motherhood—helping her becomes less rattled by stress and more attuned to her baby’s needs. Although the hypothesis remains untested, Glynn surmises this might be why moms wake up when the baby stirs while dads snore on. Other studies confirm the truth in a common complaint of pregnant women: “Mommy Brain,” or impaired memory before and after birth. “There may be a cost” of these reproduction-related cognitive and emotional changes, says Glynn, “but the benefit is a more sensitive, effective mother.”
The article reviews research that refines earlier findings on the effects of the prenatal environment on the baby. For instance, evidence is accumulating to show that it’s not prenatal adversity on its own—say, maternal malnourishment or depression—that presents risks for a baby. Congruity between life in utero and life on the outside may matter more. A fetus whose mother is malnourished adapts to scarcity and will cope better with a dearth of food once it’s born—but could become obese if it eats normally. Timing is critical too: maternal anxiety early in gestation takes a toll on the baby’s cognitive development; the same high levels of stress hormones late in pregnancy enhance it.
Just as Mom permanently affects her fetus, new science suggests that the fetus does the same for Mom. Fetal movement, even when the mother is unaware of it, raises her heart rate and her skin conductivity, signals of emotion—and perhaps of pre-natal preparation for mother-child bonding. Fetal cells pass through the placenta into the mother’s bloodstream. “It’s exciting to think about whether those cells are attracted to certain regions in the brain” that may be involved in optimizing maternal behavior, says Glynn.
Glynn cautions that most research on the maternal brain has been conducted with rodents, whose pregnancies differ enormously from women’s; more research on human mothers is needed. But she is optimistic that a more comprehensive picture of the persisting brain changes wrought by pregnancy will yield interventions to help at-risk mothers do better by their babies and themselves.
 


Provided by Association for Psychological Science
"How pregnancy changes a woman's brain." December 21st, 2011. http://medicalxpress.com/news/2011-12-pregnancy-woman-brain.html
 
Posted by
Robert Karl Stonjek

Learning left from right




Learning left from rightImage: Optogenetics meant only the key neurons in the right side of the mouse hippocampus fired. Credit: Olivia Shipton
(Medical Xpress) -- Pop psychology assertions about left-brain/right-brain differences are pretty much tosh. Our personalities are not dominated by a battle between the creative skills residing in one half of the brain competing with the hard reasoning in the other.
But that’s not to say there aren’t any differences between the left and right sides of our brains. There are some anatomical details that differ between the opposite hemispheres of the brain. Language appears to be localised more to networks in the left brain, and differences in the brain can be seen according to whether we are right-handed or left-handed.
Understanding the detail of these left-right differences – how they occur and how they underlie the processing going on in our brains – is tricky, though.
A research group based at Oxford and Cambridge universities led by Professor Ole Paulsen has been using some of the latest, most precise neuroscience techniques to get a handle on this problem.
The scientists studied recently discovered asymmetries among nerve cells involved in learning and memory processes in the mouse brain. Their findings were published in Nature Neuroscience
 
.
These particular nerve cells, or neurons, are found in the mouse hippocampus, part of the brain intimately involved in memory.
Neurons in one part of the hippocampus have different numbers of brain-chemical-responding proteins according to whether they are contacted by the left or right side of another region of the hippocampus.
The question is whether this finding of a molecular left-brain/right-brain difference is important: does it play any role in learning and memory?
Standard lab techniques for probing neurons and working out what’s going on tend to use electric currents to stimulate the nerves to fire. But such approaches would not be fine enough or accurate enough to pinpoint differences according to whether signals came from the left or right side of the hippocampus.
So the researchers used laser light and gene technology to gain extra control and be able to define exactly which neurons were being stimulated to fire. The technique, known as optogenetics, was pioneered by Professor Gero Miesenböck at Oxford.
"It enables us to be far more precise about which cells are being activated. We really gain control over what’s happening in a cell," explains Oxford DPhil student Olivia Shipton.
Olivia and her colleagues used this approach to stimulate only the key neurons on the left side of the hippocampus, or alternatively only the neurons on the right.
They then measured what this did in the neurons receiving these connections. They reasoned that if the left-right asymmetry in the hippocampus is important, there may be differences according to which side of the brain the signals came from.
They found that signals coming from the left hippocampus led to a strengthening of long-term electrical connections between neurons. This strengthening of connections is a widely accepted model of learning and memory in the brain.
"It is thought to be associated with how we lay down new memories," says Olivia.
In contrast, there were no such changes with signals coming from the right hippocampus.
"There was a striking difference. It suggests that the left and right hippocampus in the mouse have distinct functions in learning and memory processes," says Olivia.
She adds that it’s possible to speculate that the right hippocampus may provide a constant signal or context against which new learning could be compared through the left side.
The group now want to explore if this functional difference between the left and right sides of the hippocampus is important in guiding the learning of mice.
They believe it should be possible to use the same techniques to control which sides of the hippocampus fire and whether this affects a mouse’s spatial memory as it learns how to navigate mazes.
Provided by Oxford University
"Learning left from right." December 21st, 2011. http://medicalxpress.com/news/2011-12-left.html
 
Posted by
Robert Karl Stonjek