Then Show Me

 

“With my hands folded, bowing my head I pray to them as I sing about the marriage of Sita and Rama as I understand it.” (Janaki Mangala, Mangalacharana, 2)

hātha jori kari binaya sabahi sira nāvauṃ |
siya raghubīra bibāhu jathāmati gāvauṃ ||

For those following Vedic teachings, the importance of the spiritual master

 

 cannot be overemphasized. There is no over-glorification of the guru, who gives us the key to the mint that is the endless delight of bhakti-yoga, or devotional service

 

. The importance of the spiritual master is stressed repeatedly to break the living being’s tendency towards searching after the Absolute Truth through their own effort, for no human being is capable of experiencing everything or even knowing how to fully process the information that they do accumulate. For the spiritualist who learns how to describe the glories of the Supreme Lord, telling the stories of God’s pastimes and activities in their own way actually enhances the glory of their guru even further. Showing that what his guru had taught him was worthwhile and put to good use, Goswami Tulsidas

 

 embarked on singing of the marriage of Sita and Rama.

It should be noted that the story of the marriage of the beloved couple had already been told, several times in fact. First, there was the initial incident itself, which took place in the kingdom of Janakpur many thousands of years ago. We refer to this incident as being in the past, for that is how it is positioned with respect to the timeline of our current birth and the creation of the earth. However, just as the cycle of birth and death continues for the spirit soul, who travels from one body type to another, the creation itself goes through cycles of manifestation and annihilation. Not only this creation, but countless other universes follow the same pattern, which is instigated by the exhaling and inhaling of Maha-Vishnu, the Supreme Lord managing the creation. That same Vishnu ensures that the marriage of Sita and Rama takes place many times in many different creations. The marriage can be referred to as a future event as well, and also one which follows slightly different scripts. Moreover, sometimes the onlookers have their own incidents they remember, certain features they see and choose to focus on.

In this creation, the first accounts of the glorious marriage are given in the Ramayana, which was composed by Maharishi Valmiki

 

 in the Treta Yuga, the second time period of creation. In addition to touching on the event when telling the story of Rama’s life chronologically, there is another incident, after the fact, in the Ramayana where Sita Devi

 

, Rama’s wife, describes how the marriage took place. During a fourteen year stint in the forest, Sita and Rama visited many hermitages, where great sages had taken up refuge to perform their austerities and live the simple life devoted to God. They wouldn’t have to wait until the afterlife to see God, though. Their penances weren’t just for some future benefit that was unknown. Rather, they would get the fruit of their existence by having God Himself in the form of a warrior prince visit them.

Bringing His wife and younger brother with Him, Rama once came upon the hermitage of Atri Rishi and his wife Anasuya. Even during that time, Sita and Rama’s marriage was quite famous, especially since many suitors had wanted to have Janaka’s daughter’s hand in marriage. Wanting to hear the story from the coveted princess in question, Anasuya asked Sita to explain the events of that day. In this way Sita herself became a kind of spiritual master, one who described the glories of Lord Rama

 

 and His closest associates. She was at the wedding, so she could give firsthand accounts.

“I have heard, O Sita, that your hand in marriage was won by the renowned Raghava on the occasion of the self-choice ceremony [svayamvara]. O Maithili, I wish to hear that story in detail. Therefore please narrate to me the entire sequence of events as you experienced them.” (Anasuya speaking to Sita, Valmiki Ramayana

 

, Ayodhya Kand, 118.24-25)

The spiritual masters of the Vedic tradition describe the same events and the qualities of the participants in their own way, though they initially received the knowledgebase through a chain of disciplic succession. It is not that the genuine keepers of the faith make up any details or put things into their stories that aren’t true. Rather, they highlight what is important to them, incorporating different aspects of their own experiences to properly describe the glory and beauty of the Supreme Lord and His lila.

When Goswami Tulsidas embarked on writing his short song called the Janaki Mangala, there were many sources of information he could have used as reference tools. Many Puranas describe Rama’s life in varying levels of detail, and there are also the two major Ramayana compositions as well, the original by Valmiki and the version by Vyasadeva

 

 called the Adhyatma Ramayana. The latter was the one Tulsidas heard from his guru during his youth, so he was especially fond of it. In this version, Lord Shiva

 

 is the narrator, for he got to watch Rama’s activities from above in the heavenly realm. Lord Shiva is a worshipable figure himself, but he takes the most pleasure from chanting the name of Rama and describing His activities to others, including his beloved wife Mother Parvati.

Not surprisingly, when it came time to write the auspicious invocation to his song, Tulsidas referenced both Lord Shiva and Mother Parvati, and also the other worshipable personalities who keep the faith of bhakti alive and help those who are sincere in their attempt to glorify God. The first obeisance went to the guru, who planted the seed of bhakti in the young poet. When Tulsidas first heard the story of Rama from his guru, he was still too young to really understand its import or take lessons from it that would change his behavior. Nevertheless, if that hearing had not taken place, there would have been no impetus to continue ahead in learning about divine love, the topmost engagement for the spirit soul. Without first planting the seed, we cannot get the wonderful tree that produces bountiful fruits. It’s easy to get caught up in the gloriousness of the finished product and thereby forget who planted the initial seed that secured the maturation needed for the final outcome.

The saints never forget, for they are eternally indebted to their spiritual master and the devotees who helped them along the way. Since there were so many reference tools available to him, Tulsidas could have easily just done a “copy and paste” from several different scriptures and converted the words into the colloquial language he used for his songs. Following this tact would not have been harmful at all, for if the source information is perfect, then in whatever medium it is passed on through, the value of the original information will remain intact.

In the end of the invocation, which is referenced above, we see that Tulsidas bows down to his guru and the revered personalities of the Vedic tradition, praying that they are pleased with him, as he begins to sing about the marriage of Sita and Rama as he has understood it. This option is more preferable because when the disciple tells a story in his own words, in the way that he has heard the information and processed it, the output can be considered an extension of the original guru’s work. As an example, if I have a company that does building construction and I build many houses and office spaces, I get credit for the work I performed during my time on earth. Once I pass on, however, my work stops. Yet, if I can teach others the art of building and how to go about successfully constructing many such edifices during their lifetimes, whatever they build after my departure from this earth goes to my credit as well. The disciples in this case are essentially extensions of the original teacher.

In bhakti, the influence of the teacher is further expanded when the disciple produces many works. If the work comes out successful, the disciple proves that what his teacher taught him wasn’t just dry words that were meant to be memorized. Bhakti is divine love, which can be outputted in many different ways. There is no one way to love God, though the seed of devotion is first planted through the hearing process and then best cultivated through the chanting of the holy names, such as those found in the maha-mantra, “Hare Krishna Hare Krishna, Krishna Krishna, Hare Hare, Hare Rama Hare Rama, Rama Rama, Hare Hare

 

”. Hearing and chanting are the beginning, as through steady connection in consciousness with God, the individual becomes enveloped in transcendental ecstasy which then guides their behavior. Loving God can then flow through different outlets, such as writing, singing, viewing pictures, talking with others, travelling to distant places of spiritual relevance, and instructing others on the baseline principles of a life devoted to transcendentalism following divine love.

By singing about the glories of Sita and Rama, Tulsidas showed that his mind was immersed in bhakti, that he was looking for more ways to glorify the person he learned about from his guru. Information of the divine passed on to the sincere student is meant to affect behavior. If the guru passed on knowledge that was only absorbed and then not acted upon, what would their efforts really do for anyone? I could just sit and listen to any subject matter then and not gain any benefit. I could even sit there and not pay attention at all, and the effect would be the same. The guru is supremely pleased by seeing that the information he has taught has really sunk in to his students, that they have found happiness through directing their behavior towards the divine path instead of the repetitive and miserable material path. If the student wasn’t looking for a change in behavior, he never would have given aural reception to the guru’s teachings. Therefore the change in behavior is almost compulsory, as it indicates that the bhakti spirit has taken over a person residing in a realm where the materialistic spirit is predominant. The guru proves to be an ocean of mercy that constantly replenishes the soul thirsty for the transcendental nectar that is God’s association.

Religion in the vernacular sense can be taken to be a matter of faith, a rubberstamp system where you go through a few perfunctory rituals and regulations to remain in good standing with the powers that be. In more recent times, just inheriting your faith from your parents is good enough. The regulations are taken as secondary in importance, especially since material amenities are procured through personal effort rather than prayer. If I can get comfortably situated without ever attending church or praying to God, what need do I have for religion?

By writing about the subject matter as they have understood it, the bhaktas reveal the dynamic nature of real religion, which is known as sanatana-dharma in the Vedic tradition. These two terms are not sectarian, as they can be scientifically explained. Something based on science is much easier to accept than matters of faith. Sanatana means that which has no beginning and no end. Dharma means an essential characteristic, which can then be awakened and maintained through a specific set of actions. The real meaning of religion is to maintain the soul’s essential characteristic of being a lover of God. Since this feature is awakened and maintained through specific activities, dharma becomes the set of guiding principles aimed at keeping one connected with God; hence the correlation between dharma and religion. As both the soul and its primary characteristic, or dharma, are eternal, real religion continues forever [sanatana].

Sanatana-dharma is nice in theory, but the behavior of the bhaktas who have sincerely heard from their spiritual master and fully absorbed the information lends credence to the concept. Describing God as you have understood Him allows for countless opportunities for the practice of dharma to continue. As love is more than just a profession of faith or allegiance, devotional practices maintain the characteristic of lover of God within the individual. The beautiful song composed by Tulsidas showed that the teaching efforts of his guru were fruitful, and that the divine personalities beseeched were benevolent to the poet. The saints operate to please the Supreme Lord after all, and if God sees that someone is desirous of describing His glories simply based on the motive of remaining connected with Him, how can that person ever fail? Mistakes are only made by those who are conditioned, looking for perfection over the forces of matter. As Shri Rama is above both the material and spiritual energies, He can ensure that His devotees never fail in their devotional efforts. The prolific writing of the praiseworthy saints is but just one example of this truth.

In Closing:

The principles of bhakti on how to live,

Do the merciful gurus to us give.

From that sublime and glorious wisdom,

Comes knowledge of how to reach God’s kingdom.

Those who write from the principles they know,

Cause the guru’s glories and fame to infinitely grow.

An example is Janaki Mangala, which Tulsidas did write,

Brings the marriage of Sita and Rama to anyone’s sight.

Story already told many times before,

In Puranas and Ramayana’s verses galore.

Poet sung the song in his own way,

To show that guru’s words in his mind did stay.

When the Lord of creatures is to the heart pleased,

Success of devotee’s efforts is always guaranteed.

The glories of guru extend through disciple’s words,

Which heal the troubled souls travelling the three worlds.

Youngest exoplanet captured

MACQUARIE UNIVERSITY

Astronomers have revealed the first close-up images of a young planet in the process of formation in new research that aims to shed light on how planets and solar systems begin. Dr. Michael Ireland of Macquarie University and Dr. Adam Kraus of the University of Hawaii’s Institute for Astronomy have published their discovery of the planet LkCa 15 b in the Astrophysical Journal. Dr Kraus will present their findings at NASA’s Goddard Space Flight Center meeting this week. “LkCa 15 b is a gas giant, similar to Jupiter. There have been quite a few detections of Jupiter-like planets in recent years, but we’ve caught this one at the beginning of its life-cycle and orbiting a young, relatively nearby star. That’s something special to see,” said Dr. Ireland.  Using the 10 meter Keck telescopes in Hawaii and a precision optical technique called aperture mask interferometry, the astronomers were able to capture the ground-breaking images.   “We’ve been able to see, for the first time, a planet that is surrounded by dust and gas. This dusty matter is likely being deposited onto or ejected from the object,” said Dr. Ireland. “This kind of direct observation hasn’t been possible before as the light from the star is usually too bright to make accurate measurements. However, our technique enables us to account for the starlight so that we can still capture a high resolution image.” Aperture mask interferometry involves placing a small mask consisting of 9 holes in the line of light collected from a star, which is then amplified by a giant telescope such as Keck in Hawaii. “We can then manipulate the light and cancel out distortions,” said Dr. Kraus. “It’s enabled us to see inside disks of dust and gas around young stars closer than ever before. The gaps in those disks are the perfect zone for young planets in the process of formation.” Kraus and Ireland began searching for young planets through a survey of 150 young dusty stars in star forming regions, but refocused on a dozen stars as their search quickly yielded results. “LkCa 15 was only our second target, and we immediately knew we were seeing something new,” said Kraus. “We knew it was more complex than a single companion object, so we collected data several times and at differing wavelengths over 12 months to get a clearer picture,” said Ireland. “What emerged is that we had indeed captured a young gas giant in the process of formation. Theorists have made guesses about what this might look like, but to finally see it is a real milestone.” Dr’s Kraus and Ireland plan to continue their observations of nearby young stars in their efforts to construct a clearer picture of how planets and solar systems form. Of their future research, Ireland said, “studying systems like these can help us to understand more about our own solar system in relation to others out there. It’s one of those big questions – how unique are we really?” For more images of LkCa 15b click here Editor's Note: Original news release can be found here.

Maradona's Daughter! .. Amazing

women 2011.flv

Remembering to forget: Destroying bad memories and breaking bad habits

(Medical Xpress) -- Retrieving a memory is crucial when trying to extinguish it completely, according to research published today by University of Birmingham scientists in the journal Nature Communications.

Birmingham psychologists tested the hypothesis that if you cause a memory to be recalled, wait for a short time and then undertake a cue exposure or ‘extinction’ procedure this can completely disrupt and destroy the memory.

This approach could be beneficial in patients with post traumatic stress disorder or drug addiction problems. Dr Jonathan Lee, lead investigator from the University of Birmingham’s School of Psychology said: "We know that trials are ongoing in which PTSD patients are treated using drugs in a similar way – they are asked to relive their traumatic episode as part of the ‘retrieval process’ and are then given a betablocker drug. This seems to disrupt the memory and may give the patient genuine remission. Recent research suggests that this disruption of traumatic memories could be achieved by without resorting to pharmaceutical agents. We wanted to see if this also applies to the memories that underlie reward-seeking behavior."

In this study two groups of rats were used to find out whether the combination of a brief memory retrieval and extended cue exposure is enough to destroy the memory completely. In the first group, over a 9 day period, the rats learnt that when a light came on, food was given. On the 10th day the rats were given a cue exposure session, with the light presented many times without being given food. Cue exposure alone results in the light gradually losing its motivational properties as the rats were not given any food when it was switched on. However, the light quite easily recovers its motivational properties over time and with reminders.

The psychologists undertook the same process with the second group of rats, but this time the rats were given a brief reminder session, in which the light alone was presented to induce the rats to remember the light-food memory one hour prior to cue exposure. In this group, the rats became completely indifferent to the light and the link with the food was permanently broken.

Dr Lee continued: "We assessed whether the light means anything to the rats by ascertaining how much the rat is willing to work for the light, just because of its link to food. Just adding the memory retrieval renders the cue exposure much more effective. The rats appear to become completely indifferent to the light, and it seems that the light never recovers its motivational properties."

"This procedure could also be useful in treating compulsive eaters and drug addicts. By retrieving a memory – showing an addict a syringe or a compulsive eater pictures of food – and then extinguishing that memory by not giving the patient access to drugs or food we might be able to break the connection between the food and the stimulus which is predictive of the reward and that drives the behaviour. If you can break the associative link between the stimulus and the reward it loses its motivational impact on behavior."

Provided by University of Birmingham

"Remembering to forget: Destroying bad memories and breaking bad habits." October 19th, 2011. http://medicalxpress.com/news/2011-10-bad-memories-habits.html

 

Posted by
Robert Karl Stonjek

Men win humor test (by a hair)

 Psychology & Psychiatry 

 

Men just don't evolve. (winning caption); Oh, no, cavemen, is he going to eat me? (most often eliminated in the first round); In the tournament-style rating system used in the study, two captions were pitted against each other and participants chose the funnier. In this case, the top caption was the overall winner, and the bottom one was most often eliminated in the first round. Credit: © Mick Stevens/The New Yorker Collection/www.cartoonbank.com

Men are funnier than women, but only just barely and mostly to other men. So says a psychology study from the University of California, San Diego Division of Social Sciences.

While the findings support the stereotype on gender differences and humour – perhaps most vociferously and provocatively argued in recent memory by author Christopher Hitchens in his 2007 Vanity Fair article "Why Women Aren't Funny" – they also undermine the standard explanations as to why. The standard explanations are usually variations on an evolutionary sexual selection argument that likens a man's humor to a peacock's fancy tail or a deer's rack of antlers, useful primarily for showing off and impressing potential mates.

Besides, said the study's first author Laura Mickes, a postdoctoral researcher in the UC San Diego Department of Psychology and a Ph.D. graduate of the same department, "The differences we find between men's and women's ability to be funny are so small that they can't account for the strength of the belief in the stereotype."

Men edged out women by 0.11 points out of a theoretically possible perfect score of 5.0, while about 90 percent of both male and female study participants agreed with the stereotype that men are funnier.

The study, published in the journal Psychonomic Bulletin & Review, used a controlled version of The New Yorker cartoon caption contest to reach its conclusions.

Coauthors on the study are Nicholas Christenfeld, a UC San Diego professor of psychology, graduate students Drew Walker and Julian Parris, and Robert Mankoff, cartoon editor for The New Yorker.

Male prowess at the task of being funny on command, said Christenfeld, was "just at the edge of detectability," and men scored better with other men than with women.

The study team ran two separate but related experiments. The first experiment had 16 undergraduate males and 16 undergraduate females writing captions alone in a quiet room for 20 New Yorker cartoons in 45 minutes, for a total of 640 captions. All were instructed to be as funny as they could be.

Though writing captions may not be the most "natural" way to be funny, Christenfeld and Mickes explained, it has several distinct advantages, including a level playing field to determine what people are capable of doing (as opposed to what they do in social settings and day-to-day life, which could be governed by other factors). It also helps eliminate the effect of bias in the humor ratings since it is harder to tell, despite writer V.S. Naipaul's claims to the contrary, whether the writer is a man or a woman from written words alone.

The second phase of the first experiment had 34 male and 47 female undergraduates helping to rate the captions written earlier in a five-round knockout tournament: One cartoon image was displayed with two random and anonymous captions, and the raters chose the funnier of the two at their own pace. The process, with new captions each time, was repeated for all 32 captions for each cartoon. The 16 winning captions of round one were then randomly pitted against each other and so on. The number of rounds, from zero to five, that captions survived before being knocked out determined the writers' average scores.

True to the conventional wisdom, men did better than women, but not by much: Male writers earned an average 0.11 more points than female writers. But what's even more interesting, the researchers say, and what runs contrary to the standard explanations of why men might be funnier, is that men did better with other men: Female raters allocated only an average 0.06 more points to the male writers, while the male raters gave them a significantly higher average of 0.16 more points.

"Sad for the guys," Christenfeld said, "who think that by being funny they will impress the ladies, but really just impress other men who want to impress the ladies."

In a second, related experiment, the researchers tested memory and memory bias to see if men are credited with being funnier than they really are.

As expected, funny captions were remembered better than unfunny ones. The authors of funny captions were remembered better too. But humor was more often misremembered "as having sprung from men's minds," the researchers write. And, even more telling, Mickes said, when the study participants were guessing at authors' gender, unfunny captions were more often misattributed to women and funny captions were more often misattributed to men.*

So if the study is right and men are just a skosh more funny, why might that be? In analyzing the content of the captions, the researchers noted that men used profanity and sexual humor a little more frequently (about 4 vs. 2 percent of the time), but that didn't seem to account for the "win" since that style of caption didn't necessarily do better, with either sex.

It could be that men see more opportunities to take a stab at humor, said Christenfeld. It could be that they try harder or more often.

As The New Yorker cartoon editor Mankoff observed on his blog in May, after film critic Roger Ebert won the caption contest on his 107th try: Nine of the top 10 most devoted entrants, or "überenterers," are men. While fewer women win the actual contest, far fewer of them enter. When they do enter, though, their success rates are pretty impressive. Looking at contests #250 through #282, there are 32 winners, with 22 men and 10 women, Mankoff writes: "The 22 winning men entered an average of 70.22 contests, but the 10 women averaged 6.4 entries – and four of them won on their first attempt."

It remains for further research to ferret out the reasons men might be the marginally funnier sex. In the meanwhile, the current paper had one other finding worth noting: When asked to predict their own performance on a scale of one to five, the men figured they'd get a 2.3, and the women, a more modest 1.5. That is, the difference in self-assessment was greater than the actual difference detected by the contest. "Male confidence, in this domain at least," the researchers write, "does seem to outstrip male competence."

*Mickes declined to make any funny comments because they'd be attributed to her male coauthors anyway.

Provided by University of California - San Diego

"Men win humor test (by a hair)." October 19th, 2011. http://medicalxpress.com/news/2011-10-men-humor-hair.html

 

Posted by

Robert Karl Stonjek

X-linked mental retardation protein is found to mediate synaptic plasticity in hippocampus

 in Neuroscience 

Scientists at Cold Spring Harbor Laboratory (CSHL) have solved part of a puzzle concerning the relationship between changes in the strength of synapses – the tiny gaps across which nerve cells in the brain communicate – and dysfunctions in neural circuits that have been linked with drug addiction, mental retardation and other cognitive disorders.

A team led by CSHL Professor Linda Van Aelst has pieced together essential steps in a signaling cascade within excitatory nerve cells that explains a key phenomenon called longterm depression, or LTD. The "depression" in question has nothing to do with the human illness with that name. Rather, it refers to a tamping-down of the strength of individual synapses – what scientists call synaptic plasticity.

The mechanism behind LTD is called endocytosis. It involves a retraction of receptors where neurotransmitters can "dock." Van Aelst and colleagues have demonstrated how LTD works following activation of a class of receptors called group I metabotrobic glutamate receptors, or mGluRs.

It was known that longterm depression mediated by mGluRs depended in part on the rapid synthesis of specific proteins. Yet the identity of these proteins had largely remained a mystery. The CSHL scientists have now shown that locally rapid production of a protein called oligophrenin 1 (OPHN1) follows activation of group I mGluRs. OPHN1 in turn was shown to mediate LTD in hippocampal nerve cells, by interacting with yet another protein called EndophilinA2/3.

The result of this cascade of intracellular signals was dramatic: persistent removal of AMPA-type receptors at the excitatory synapse, and the onset of LTD. When rapid production of OPHN1 was blocked, mGluR-dependent LTD did not occur. These findings appear online today ahead of print in the journal Neuron.

Van Aelst explained the significance of the finding. "OPHN1 has two important functions that we know about. One is early in development, after synapses have appeared in the emerging nervous system. In this phase, OPHN1 in concert with other factors stabilizes receptors at synapses, and thus is essential in maintaining the structure of these essential features of neural circuitry.

"Our new findings show another vital role for OPHN1, later in development and into maturity. We assume that in response to behavioral stimuli – we aren't yet sure what kind – mGluRs are activated, setting off the series of steps that we identified: rapid upregulation of OPHN1, which binds to EndophilinA2/3, which in turn mediates the long-term removal of AMPA receptors."

OPHN1 is known to be associated with X-linked mental retardation and with other cognitive and behavioral deficits. The team hypothesizes that OPHN1-related changes in plasticity such as those described in their new work may be causally related to such pathology. They are investigating this possibility in their current work.

More information: "Rapid Synthesis of the X-linked Mental Retardation Protein OPHN1 Mediates mGluR-Dependent LTD through Interaction with the Endocytic Machinery" appears online ahead of print October 19 in Neuron. 

Provided by Cold Spring Harbor Laboratory

"X-linked mental retardation protein is found to mediate synaptic plasticity in hippocampus." October 19th, 2011.http://medicalxpress.com/news/2011-10-x-linked-mental-retardation-protein-synaptic.html

 

Posted by
Robert Karl Stonjek

Neuroscientists find normal brain communication in people who lack connections between right, left hemispheres

 in Neuroscience 

 

(Top) Magnetic resonance images comparing a healthy subject (left) with an AgCC patient (right). The corpus callosum is the thick, 'c'-shaped structure outlined in the healthy brain and missing from the AgCC brain. (Bottom) Functional magnetic resonance images highlight symmetric patterns of synchronized activity in both healthy (left) and AgCC subjects (right) during rest with eyes closed. More than 15 of this type of network were found to be preserved in AgCC subjects. [Credit: California Institute of Technology]

(Medical Xpress) -- Like a bridge that spans a river to connect two major metropolises, the corpus callosum is the main conduit for information flowing between the left and right hemispheres of our brains. Now, neuroscientists at the California Institute of Technology (Caltech) have found that people who are born without that link—a condition called agenesis of the corpus callosum, or AgCC—still show remarkably normal communication across the gap between the two halves of their brains.

Their findings are outlined in a paper published October 19 in The Journal of Neuroscience.

Our brains are never truly at rest. Even when we daydream, there is a tremendous amount of communication happening between different areas in the brain. According to J. Michael Tyszka, lead author on the Journal of Neuroscience paper and associate director of the Caltech Brain Imaging Center, many areas of the brain display slowly varying patterns of activity that are similar to one another. The fact that these areas are synchronized has led many scientists to presume that they are all part of an interconnected network called a resting-state network. Much to their surprise, Tyszka and his team found that these resting-state networks look essentially normal in people with AgCC, despite the lack of connectivity.

“This was a real surprise," says Tyszka. "We expected to see a lot less coupling between the left and right brain in this group—after all, they are missing about 200 million connections that would normally be there. How do they manage to have normal communication between the left and right sides of the brain without the corpus callosum?”

The work used functional magnetic resonance imaging (fMRI) to demonstrate that synchronized activity between the left and right brain survives even this sort of radical rewiring of the nerve connections between the two hemispheres. The presence of symmetric patterns of activity in individuals born without a corpus callosum highlights the brain’s remarkable plasticity and ability to compensate, says coauthor Lynn Paul, research staff member and lecturer in psychology at Caltech. “It develops these fundamental networks even when the left and right hemispheres are structurally disconnected.”

The study that found the robust networks is part of an ongoing research program led by Paul, who has been studying AgCC for several decades. AgCC occurs in approximately one of every 4000 live births. The typical corpus callosum comprises almost 200 million axons—the connections between brain cells—and is the largest fiber bundle in the human brain. In AgCC, those fibers fail to cross the gap between the hemispheres during fetal development, forcing the two halves of the brain to communicate using more indirect and currently unknown means.

“In the 1960s and 1970s, Roger Sperry at Caltech studied 'split-brain' patients in whom the corpus callosum was surgically severed as a treatment for epilepsy," explains Paul. "Our research on AgCC has moved in a different direction and focuses on a naturally occurring brain malformation that occurs before birth. This allows us to examine how, and to what extent, the brain can compensate for the loss of the corpus callosum as a person grows to adulthood.”

According to the team, the findings are especially valuable in light of current theories that link impaired brain connections with clinical conditions including autism and schizophrenia.

“We are now examining AgCC subjects who are also on the autism spectrum, in order to gain insights about the role of brain connectivity in autism, as well as in healthy social interactions," says Tyszka. "About a third of people with AgCC also have autism, and altered connectivity in the corpus callosum has been found in autism. The remarkable compensation in brain functional networks that we found here may thus have important implications also for understanding the function of the brains of people with autism."

More information: "Intact bilateral resting-state networks in the absence of the corpus callosum," The Journal of Neuroscience.

Provided by California Institute of Technology

"Neuroscientists find normal brain communication in people who lack connections between right, left hemispheres." October 19th, 2011.http://medicalxpress.com/news/2011-10-neuroscientists-brain-people-lack-left.html

 

Posted by
Robert Karl Stonjek

IQ can rise or fall significantly during adolescence, brain scans confirm

 Neuroscience 

IQ, the standard measure of intelligence, can increase or fall significantly during our teenage years, according to research funded by the Wellcome Trust, and these changes are associated with changes to the structure of our brains. The findings may have implications for the testing and streaming of children during their school years.

Across our lifetime, our intellectual ability is considered stable, with Intelligence Quotient (IQ) scores taken at one point in time used to predict educational achievement and employment prospects later in life. However, in a study published today in the journal Nature, researchers at the Wellcome Trust Centre for Neuroimaging at UCL (University College London) and the Centre for Educational Neuroscience show for the first time that, in fact, our IQ is not constant.

The researchers, led by Professor Cathy Price, tested thirty-three healthy adolescents in 2004 when they were between 12 and 16 years old. They then repeated the tests four years later when the same subjects were between 15 and 20 years old. On both occasions, the researchers took structural brains scans of the subjects using magnetic resonance imaging (MRI).

Professor Price and colleagues found significant changes in the IQ scores measured in 2008 compared to the 2004 scores. Some subjects had improved their performance relative to people of a similar age by as much as 20 points on the standardised IQ scale; in other cases, however, performance had fallen by a similar amount. In order to test whether these changes were meaningful, the researchers analysed the MRI scans to see if there was a correlation with changes in the structure of the subjects' brains.

"We found a considerable amount of change in how our subjects performed on the IQ tests in 2008 compared to four years earlier," explains Sue Ramsden, first author of the study. "Some subjects performed markedly better but some performed considerably worse. We found a clear correlation between this change in performance and changes in the structure of their brains and so can say with some certainty that these changes in IQ are real."

The researchers measured each subject's verbal IQ, which includes measurements of language, arithmetic, general knowledge and memory, and their non-verbal IQ, such as identifying the missing elements of a picture or solving visual puzzles. They found a clear correlation with particular regions of the brain. An increase in verbal IQ score correlated with an increase in the density of grey matter – the nerve cells where the processing takes place – in an area of the left motor cortex of the brain that is activated when articulating speech. Similarly, an increase in non-verbal IQ score correlated with an increase in the density of grey matter in the anterior cerebellum, which is associated with movements of the hand. However, an increase in verbal IQ did not necessarily go hand-in-hand with an increase in non-verbal IQ.

According to Professor Price, a Wellcome Trust Senior Research Fellow, it is not clear why IQ should have changed so much and why some people's performance improved whilst others' decline. It is possible that the differences are due to some of the subjects being early or late developers, but it is equally possible that education played a role in changing IQ, and this has implications for how schoolchildren are assessed.

"We have a tendency to assess children and determine their course of education relatively early in life, but here we have shown that their intelligence is likely to still develop," says Professor Price. "We have to be careful not to write off poorer performers at an early stage when their IQ may improve significantly given a few more years.

"It's analogous to fitness. A teenager who is athletically fit at 14 could be less fit at 18 if they stopped exercising. Conversely, an unfit teenager can become much fitter with exercise. "

Other studies from the Wellcome Trust Centre for Neuroimaging and other research groups have shown that the brain's structure remains 'plastic' throughout adulthood. For example, Professor Price showed recently that guerrillas in Columbia who had learned to read as adults had a higher density of grey matter in several areas of the brain's left hemisphere than those who had not learned to read. Professor Eleanor Maguire, also from the Wellcome Trust Centre, showed that part of a brain structure called the hippocampus, which plays an important role in memory and navigation, has a greater volume in licensed London taxi drivers.

"If our brain structure can change throughout our adult lives, can our IQ also change?" adds Professor Price. "My guess is yes. Plenty of evidence suggests that our brains can adapt and their structure changes, even in adulthood."

'Understanding the brain' is one of the Wellcome Trust's key strategic challenges. It funds a significant portfolio of neuroscience and mental health research, ranging from studies of molecular and cellular components to work on cognition and higher systems. At the Wellcome Trust Centre for Neuroimaging, clinicians and scientists study higher cognitive function to understand how thought and perception arise from brain activity, and how such processes break down in neurological and psychiatric diseases.

"This interesting study highlights how 'plastic' the human brain is," said Dr John Williams, Head of Neuroscience and Mental Health at the Wellcome Trust. "It will be interesting to see whether structural changes as we grow and develop extend beyond IQ to other cognitive functions. This study challenges us to think about these observations and how they may be applied to gain insight into what might happen when individuals succumb to mental health disorders."

More information: Ramsden, S et al. Verbal and nonverbal intelligence changes in the teenage brain. Nature, October 20, 2011. DOI: 10.1038/nature10514

Provided by Wellcome Trust

"IQ can rise or fall significantly during adolescence, brain scans confirm." October 19th, 2011. http://medicalxpress.com/news/2011-10-iq-fall-significantly-adolescence-brain.html

 

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Robert Karl Stonjek

Technology Targets Genetic Disorders Linked to X Chromosome

 by Biomechanism 

Geneticists at Emory University School of Medicine have demonstrated a method that enables the routine amplification of all the genes on the X chromosome. The technology allows the rapid and highly accurate sequencing and identification of novel genetic variants affecting X chromosome genes.

The method, developed in cooperation with RainDance Technologies, is described in the Oct. 2011 issue of Genomics. Senior author Michael Zwick, PhD, assistant professor of human genetics at Emory University School of Medicine, is using the method to identify genetic variants that contribute to autism spectrum disorders.

Because the X chromosome is a hotspot for genes that are suspected of contributing to autism and intellectual disability, the Emory team’s finding could speed new discoveries and eventually make routine clinical diagnosis of autism and intellectual disability easier.

“This technology has the potential to be a valuable tool for genetic researchers across a wide variety of applications,” Zwick says. “Our data shows that it can support the routine sequencing of the exons of the human X chromosome in a uniform, accurate and comprehensive way.”

The team’s sequencing method does not read all the letters of the genetic code in the X chromosome from beginning to end. Instead, it targets more than 800 “exons”: all the genes that get read out and made into RNA.

A direct comparison with another method of target selection called oligonucleotide capture showed that the team’s technique needed between three and seven times fewer sequence reads to achieve high levels of accuracy and completeness, potentially meaning lower costs.

The Emory team’s experiments showed that their technique could read 97 percent of targeted sequences at high depth with an accuracy of 99.5 percent. The team used data from the HapMap Project, a partnership coordinated by the Human Genome Research Institute, as a reference standard for genetic sequence variation.Sex is determined by having two X chromosomes (female) or an X and a Y chromosome (male). Because males have only a single X chromosome, a mutation in a gene on the X chromosome is more likely to affect a male than a female because males lack another copy of the same gene to compensate. This pattern of inheritance can contribute to disorders that disproportionately affect males, such as autism spectrum disorder or intellectual disability.

Modern DNA sequencing techniques use the polymerase chain reaction (PCR) to isolate and “amplify” the target DNA scientists want to read. RainDance Technologies has developed a single molecule microdroplet-based technology that enables scientists to target up to 20,000 genomic loci in a single sample, saving time, space and cost while increasing reliability and ease of use. The reactions take place in millions of self-contained droplets, allowing each to amplify a different piece of DNA within an emulsion.

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Reference:

K. Mondal, A.C. Shetty, V. Patel, D.J. Cutler and M.E. Zwick. Targeted sequencing of the human X chromosome exome. Genomics Vol. 98, Issue 4, pp. 260-265 (Oct. 2011).

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