Tuesday, October 30, 2012

Early Autism Treatment Benefits Kids' Brains

Early, intensive autism treatment improves children's brain development, a new study shows.
The treatment, dubbed Early Start Denver Model or ESDM, offers a child 20 hours a week of one-on-one treatment with a trained therapist. It also calls for many more hours of the treatment, in the form of structured play, with a parent trained in the technique.

By age 4, children given the treatment had higher IQ scores, more adaptive behavior, better coordination, and a less severe autism diagnosis than kids given the standard autism treatments offered in their communities. But that's not all, researchers Geraldine Dawson, PhD, and colleagues report.

"We jump-started and improved the responses of children's brains to social information," says Dawson, professor of psychiatry at the University of North Carolina and chief science officer at Autism Speaks.

Normal child development depends on interactions with parents and other people. Without such interactions, language and social skills do not develop.

As measured by an electroencephalogram (EEG), small children's brains show a specific pattern of activity when they look at a picture of a human face. This doesn't happen when they look at pictures of inanimate objects.

Just the reverse happens in children with autism. Their brains light up when they look at pictures of objects, but not when they look at faces. This changed dramatically in the children treated with ESDM.

"The [brains of] children who received the ESDM looked virtually identical to typical 4-year-olds," Dawson says. "The children that received the interventions normal in their communities continued to show the reversed pattern."

Changing Brain Development

The treated children weren't cured. They still had autism, Dawson says. But they are continuing to improve.
"These interventions not only alter the trajectory of behavioral development in a child with autism, but also brain development," Dawson says.

Brain development in children given a behavioral autism treatment likely means these children are learning to "work around" their autism, suggests Arthur L. Beaudet, MD, professor of molecular and human genetics, pediatrics, and molecular and cellular biology at Baylor College of Medicine, Houston.

"To the extent early intervention helps brain development, it is more likely to help by letting the brain compensate and get around the problems rather than reverse them," Beaudet says. "We do know if you damage the brain of a young child, like in an accident, the infant brain has a tremendous ability to recover and get around the problem."

Key to Autism Treatment: Start Early

Although she and her colleagues developed the ESDM treatment, Dawson is quick to point out that it's not the only effective autism treatment. The key, she says, isn't the treatment -- it's the timing.

"The important point is early diagnosis," she stresses. "By starting early, we have the best chance of providing these kids with the best possible outcomes."

One key to early diagnosis might be the EEG test used to evaluate outcomes in this study.

"There has already been published data showing these early EEG measures are detecting babies at risk of autism at 12 months of age. They have this unusual pattern of not showing a normal response to social stimuli," she says.

'Brain-dead' definition flawed, says ethicist

PATIENTS in intensive care are being declared brain dead for organ donation when they may still be legally alive, the Melbourne bioethicist Nicholas Tonti-Filippini says in a new book.

He says medical practice has moved ahead of the law by accepting a lesser standard of brain death than the law prescribes: the irreversible loss of all brain function.

A new standard has taken hold in intensive care units in which the crucial aspect is absence of consciousness, Professor Tonti-Filippini said.

''They are diagnosing brain death while there is still some mid-brain function. They say 'so what?', because the person is not conscious,'' he said.
If the mid-brain was functioning, then the brain would still control some bodily functions such as hormone production and blood pressure control. The only way to be certain was an imaging test that showed there was no blood flow to the brain, he said, but most Victorian hospitals used a clinical test for brain-stem function instead.

A spokesman for the intensive care society that establishes the brain death criteria (ANZICS), Associate Professor Bill Silvester, said Professor Tonti-Filippini was wrong, and potentially putting at risk the lives of critically ill people awaiting organ donation.

Professor Silvester, of the Austin Hospital, said a recent World Health Organisation forum on brain death explicitly regarded the ANZICS criteria as ''an exemplar of rigour''.

He said clinical testing, such as breathing, was the main way to determine death, including the mid-brain. The only need for extra testing, such as blood flow, was when clinical criteria could not be resolved. No patient had ever recovered when the clinical determination of brain death had been conducted correctly.
''ANZICS believes these unsubstantiated claims by Professor Tonti-Filippini risk damaging public confidence in a very rigorous process,'' he said.

But Professor James Tibbals, deputy director of intensive care at the Royal Children's Hospital and its medical director of organ donation, has endorsed Professor Tonti-Filippini, arguing that the current ANZICS test for brain death is neither legal nor ethical, and that most donors cannot be proven to be truly dead when organs are removed.

He said in a 2008 scientific paper that the blood-flow test was the only safe and reliable one, and was relatively simple and cheap.

The clinical tests used in most Victorian hospitals, such as testing breathing, could be misleading, as well as harmful or fatal for the patient. All the experts agreed that the absence of blood flowing in the brain meant irreversible loss of all brain function and therefore the patient was definitely dead. But requiring this stricter understanding meant organs could not be transplanted in some circumstances when they were now, which is why the donor community disliked Professor Tibbals' stance.

Professor Tonti-Filippini said the new definition, which had crept in gradually with no watershed moment, was of particular concern to religious people.

''It's enormously significant to the church because people are being diagnosed as dead and their organs are being taken when, as a matter of faith, you'd say they were alive,'' he said.

Most religious people understood death as the separation of soul and body, and accepted that had occurred with the irreversible loss of all brain function. But under the consciousness model a person could be declared dead while the hormones still worked and blood pressure was still controlled by the brain.

''I would say such a person is severely disabled, but you can't say dead,'' he said. ''We have moved from wanting to be absolutely certain that this person is dead to saying, 'This person is in such a state they might as well be dead'.''

He said religious people should insist on further tests showing there was no blood supply before endorsing organ donation.

Time Magazine on ‘How Cannabinoids May Slow Brain Aging’

Time Magazine‘s Maia Szalavitz does good work Monday with a piece reviewing some clinical evidence on cannabinoids – the molecules in marijuana – and aging. The brain’s own cannabinoid system is responsible for stopping inflammation, and “a sort of anti-oxidant cleanse, removing damaged cells and improving the efficiency of the mitochrondria, the energy source that powers cells, ultimately leading to a more robustly functioning brain.” Stimulating it with cannabinoids increase brain-derived neurotrophic factor which protects brain cells and promotes neuron growth, and – bucking the stereotype – maintains normal cognitive function in old age.

But politics keeps scientists from exploring pot for cures to Alzheimer’s and Parkinson’s Disease, researchers say. Gary Wenk, professor of neuroscience, immunology and medical genetics at Ohio State University wrote: “In my experience, working in this area is like touching the third rail. … I get hate and love mails that are bizarre and phone messages from people too high to talk. Some of my colleagues have left the area after seeing their names in the National Enquirer… I do not blame a war on marijuana but rather the public’s prejudice and extreme bias. I’ve now discontinued my research on this system.”

“He and others in the field are not completely pessimistic, however,” Szalavitz writes. “He says, ‘I’ve been trying to find a drug that will reduce brain inflammation and restore cognitive function in rats for over 25 years; cannabinoids are the first and only class of drugs that have ever been effective. I think that the perception about this drug is changing and in the future people will be less fearful.’”

Awareness about infection caused by ‘brain-eating amoeba’ urged

Like many water-borne bacterial and viral diseases, Naegleria fowleri, an amoebic infection, has emerged as a health threat across Pakistan.

Though the infection is not highly prevalent but reporting of its recent cases in various areas of Pakistan, particularly Karachi, has necessitated the need for specific attention of the concerned authorities.

So far, there is no specific treatment available for Naegleria fowleri infection nor any vaccine is available to prevent it. Many health experts believe that the only way to avoid the deadly infection is preventive measures. It is believed that over 95 per cent of the confirmed cases of the infection have to face death despite treatment.

The amoeba that causes the infection is also called as ‘brain-eating amoeba’, named after the most common complication produced by this infection, primary amoebic meningoencephalitis (PAM), which is usually a fatal complication. This condition directly involves the spread of infection to the brain substance itself causing high mortality rate, said Assistant Professor of Microbiology Dr. Humaira Zafar while talking to ‘The News’ in connection with precautionary measures needed to avoid the infection.

She added that the presentations of infection after the entry of ameba into body through nasal cavity can range from changes in taste and smell, nausea, vomiting, headache, fever, and stiff neck. “In severe cases when disease progresses, confusion, hallucinations, lack of attention, and coordination in body movements can easily be manifested ultimately leading to seizures/fits and death within 14 days of the infection.”

She said that the case fatality rate of the infection is estimated at 98 per cent and the symptoms of the infection start about five days (range is from one to seven days) after exposure.

Dr. Humaira explained that Naegleria fowleri is a free-living amoeba and typically found in contaminated stagnant and contaminated water, such as ponds, lakes, rivers, and hot springs. It is also found in soil especially near the warm water discharges of industrial plants, and non-chlorinated or poorly chlorinated swimming pools. Rarely, it can appear in inadequately treated samples of home-based tap water that is not treated enough to be entirely potable, though this is not the usual method of contracting the illness unless the water is very deeply inhaled, usually deliberately, she said.

She further explained that the predisposing factors for the transformation of inactive to active form of Naegleria fowleri induces food deprivation, crowding, desiccation, accumulation of waste products, and cold temperatures. “The ideal temperature is the changing temperatures ranging from 25°C to 42°C.”

She said that no specific treatment options and vaccine is available for the infection while the prognosis for infected patients is also very poor. “More than 95% of infections are fatal despite treatment. Survivors may have residual neurological problems, such as seizure disorders.”

She said that the only way to reduce the spread of infection is avoiding contact with contaminated sources. This is only possible if access to safe and chlorinated water sources be ensured, she said.

Dr. Humaira said that apart from preventive measures, there needs adoption of proper diagnostic approaches by the examination of Brain Fluid (Cerebro spial fluid) culture and PCR studies are the mainstay of diagnostic approaches. She said that awareness among public should be created on the subject and patients of the infection should fully cooperate with the doctors on the subject of collection of brain fluid so that their management can be started soon.

Saturday, October 20, 2012

How our brains work to erase bad memories

Got a bad memory? The brain has a unique way of helping you forget.
Say you’re on a date and you trip and fall so your dress rides up and he sees your underwear. Or your boss tells you that for the third year in the row there will be no raises. Both of these experiences feel uncomfortable, but what do you do to forget these awkward memories? Researchers found that we use two different ways -- suppression or substitution -- to avoid thinking of uncomfortable or unhappy memories.

“We assume that, in everyday life, healthy people will use a mixture of both mechanisms to prevent an unwanted memory from coming to mind,” says Roland Benoit, a scientist at the Medical Research Council, Cognition and Brain Sciences Unit at University of Cambridge, via email. “We did not know whether the processes of direct suppression and thought substitution can be isolated, and which, if any of them, would actually cause forgetting.” 

Roland and his co-author, Michael Anderson, asked 36 adults to participate in a memory exercise where half suppressed memories and the other half substituted new memories. The researchers hoped to understand how we voluntarily forget and how it affects general memory. The subjects were tested during magnetic resonance imaging procedures, or MRIs, allowing the researchers to observe how the brain works during suppression and substitution.

While both processes cause forgetting, a different region of the brain controls each one. When people suppress memories, the dorsal prefrontal cortex inhibits activation in the hippocampus, which plays an important role in retaining memories.

“It thus effectively breaks the remembering process. This, in turn, disrupts the memory representations that would be necessary for recalling the unwanted memory later on,” Benoit explains.

When it comes to substitution, the brain works a bit differently -- the caudal prefrontal cortex and midventrolateral prefrontal cortex form a network of sorts that works with the hippocampus to swap out new information with details people would soon forget.

“By just looking at how well people forgot memories, you couldn’t tell whether they had done direct suppression or thought substitution,” Benoit says. “These mechanisms are based on different brain systems that work in opposite fashion: One (direct suppression) by ‘slamming the mental break’ to stop the remembering process and the other (thought substitution) by steering the remembering process towards a substitute memory.”

Even though people exploit both to forget those nagging, unwanted memories, actively overlooking unpleasant events can negatively impact how we remember. But Benoit notes that learning how people deal with unwanted memories helps them understand how people with traumatic memories, such as PTSD sufferers, cope with remembering. 

“It is perfectly natural for people, upon encountering an unwelcome reminder, to try to put the unpleasant reminding out of mind. We all have experienced this.  Intuitively, it feels as though we solved this problem.” 

Fish oil helped save our son

Bobby Ghassemi was just 17 years old when he was in a horrific car accident. Bobby Ghassemi was just 17 years old when he was in a horrific car accident. 

After the accident in March 2010, doctors told Bobby's family that he could live out the rest of his life in a vegetative state. After the accident in March 2010, doctors told Bobby's family that he could live out the rest of his life in a vegetative state.

(CNN) -- Time seemed to slow as Marjan Ghassemi saw her 17-year-old son, Bobby, lying in a hospital bed after a car crash.

He had a thick band of gauze wrapped around his head and a tangle of tubes protruding from his body. A hole was cut into his windpipe, and the hollow-sounding hiss of machines helping him breathe filled the room.
At that point, there was no telling whether he would live or die, but Marjan was determined not to cry.

"From day one, when we got there, I didn't want him to know we were crying, that we were upset," she said. "I wanted all positive energy in the room.

Ten days after the accident, Bobby was still in a coma. Bobby's father, Peter, talked with Dr. Michael Lewis, who suggested that omega-3 fatty acids might be able to help. Peter insisted that his son be given high doses of fish oil through a feeding tube. Ten days after the accident, Bobby was still in a coma. Bobby's father, Peter, talked with Dr. Michael Lewis, who suggested that omega-3 fatty acids might be able to help. Peter insisted that his son be given high doses of fish oil through a feeding tube.  
"I went in his ear and said ... 'You fight your way and come back to us.' "

It was March 2010. Bobby Ghassemi had been driving fast along a winding road in Virginia when his car barreled off the road. By the time paramedics arrived, he was in a coma and barely alive.

"For all intents and purposes, he was dead on the scene," said Dr. Michael Lewis, a physician who later advised the family. "I'm looking at the reports, and they report a Glasgow Coma Score of 3. A brick or a piece of wood has a Glasgow Coma Score of 3. It's dead."

Ghassemi was airlifted to a hospital. For the first three days, it was touch and go.

Ghassemi's brain was so engorged, doctors needed to relieve the pressure by taking out a portion of his skull. He also had what is called diffuse axonal injury: bleeding that suffused nearly every part of his brain.
"His doctor said to me, 'Listen, he has survived. It is a miracle that he lived, that he made it,' " Marjan Ghassemi said. " 'If he comes out of the coma ... I don't know if he's going to be a vegetable for the rest of his life or whether he'll remember anybody.' "

Bobby says the omega-3 fatty acids have helped in recovering his motor skills. Bobby says the omega-3 fatty acids have helped in recovering his motor skills.  
Ten days later, as Bobby lay comatose but stable, his father, Peter Ghassemi, was sick of waiting and desperate for an intervention. After a series of phone calls to friends, he ended up speaking with Lewis, an Army colonel and doctor.

After some discussion, Lewis proposed something that Peter Ghassemi had never heard about for traumatic brain injuries: fish oil.

At that point, Peter Ghassemi was open to anything.

"Every minute passing was hurting my son ... because they weren't really doing anything to help him besides keeping him alive and stabilizing all of his vital signs," he said. "If there was a chance to improve, I wanted it to be done right then."

'He was really in dire straits'
Fish oil -- which is composed of omega-3 essential fatty acids, also found in the brain -- had been used only once before to treat a brain injury as devastating as Ghassemi's. That was in 2006, in the case of Randal McCloy, the sole survivor of a mine disaster in West Virginia.

McCloy, 26, was trapped in a mine for 41 hours while the air around him and 12 other miners filled with noxious methane and carbon monoxide. By the time he was pulled from underground, he had had a heart attack, was in liver and kidney failure and had a collapsed lung, according to his doctors.

His brain was also riddled with damage from the carbon monoxide and methane.

McCloy's prognosis was not very different from Ghassemi's. According to his neurosurgeon at the time, Dr. Julian Bailes, restoring McCloy's normal brain function was truly a long shot.

"Randy was really on death's doorstep," said Bailes, now co-director of NorthShore Neurological Institute in Evanston, Illinois. "He was really in dire straits."

Like with Ghassemi, once McCloy was stabilized, there was little doctors could do to stem the tide of inflammation and cell death occurring in his brain.

But Bailes and other doctors on McCloy's team resisted the "wait and see" course common in these types of cases and began an unorthodox treatment regimen, including hyperbaric oxygen treatments and high doses of fish oil.

"The concept was then trying to rebuild his brain with what it was made from when he was an embryo in his mother's womb," Bailes said.

The brick wall analogy
That's the theory behind using omega-3 fatty acids to heal brain injury. The human brain, which itself is a fatty mass, is about 30% composed of omega-3 fatty acids, according to Lewis.

In his words, high doses of omega-3 fatty acids, since they mirror what is already in the brain, could facilitate the brain's own natural healing process.

"It really gets down to what I would call my brick wall analogy," Lewis said. "If you have a brick wall and it gets damaged, wouldn't you want to use bricks to repair the wall? And omega-3 fatty acids are literally the bricks of the cell wall in the brain."

Most of the studies about omega-3 for traumatic brain injury are in animals, but they indicate potential for healing the human brain.

After a trauma, the brain tends to swell, and the connections between some nerve cells can become damaged, while other cells simply die.

National Institutes of Health research suggests that omega-3 fatty acids may inhibit cell death and could be instrumental for reconnecting damaged neurons.

Another recent study revealed genes that are activated to contain massive damage -- especially inflammation -- when the brain is injured. What activates those genes: omega-3.

"We have strong data that suggest omega-3 will activate good proteins to cope with brain damage and turn off proteins that cause neuroinflammation," said Dr. Nicolas Bazan, director of the Neuroscience Center of Excellence at LSU Health in New Orleans and author of the study.

And besides that, according to Bailes and Lewis, fish oil may be the only solution for brain damage that continues after a traumatic brain injury patient has been stabilized.

"There is no known solution; there's no known drug; there's nothing that we have really to offer these sorts of patients," said Bailes, who along with Lewis received money from companies that make fish oil after their treatment of Ghassemi and McCloy.

The damage to McCloy's brain was profound, according to Bailes. Not only did it experience massive cell death, the protective sheath around McCloy's nerve cells had been stripped during the hours of exposure to toxic gases. That sheath, called myelin, allows brain cells to communicate with one another.

Bailes consulted with a fish oil expert and eventually decided that administering 20 grams a day of omega-3 fish oil through a feeding tube might repair the myelin sheath. (For comparison: A typical supplemental dose for someone with an uninjured brain is about 2 grams a day.)

"We decided to throw the kitchen sink at him," Bailes said. "If we were going to fail, we were going to fail with all guns blazing, so we gave him a very high, unprecedented dose to make sure we saturated and got high levels in the brain."

Less than three weeks after the mine disaster, McCloy was emerging from his coma. Three months after that, he was walking and speaking.

Citing McCloy's dramatic recovery, Lewis spoke with Peter Ghassemi about introducing omega-3 for his son. After that conversation, Peter Ghassemi was convinced and began to pressure his son's doctors.

"It was a fight," Peter Ghassemi said. "They didn't believe, and they said, 'Fine, the West Virginia miner was one case. Bring me 999 more cases, a thousand more cases ... before I can give it to your son.' "

But eventually they conceded, and Bobby Ghassemi was started on high-dose fish oil therapy, at a dosage that mirrored what Bailes had given to McCloy in 2006.

'The whole place was cheering for me'
Two weeks after beginning the regimen, Ghassemi was emerging from his coma.

"We saw hand movements on the left side," Peter Ghassemi said. "Around the fifth or sixth week, there was some movement, and then his hands started moving more, the leg was moving more."

Soon after that, Bobby began to show signs of recognizing his family and his dog and of discerning things like colors and numbers. Slowly, his brain was recovering, and his family ardently believes that the high-dose fish oil is the reason why.

"His brain was still recovering, but with (omega-3), it recovered much faster and in a shorter amount of time," Peter Ghassemi said. "His brain was damaged, and this was food for the brain."

Three months after his accident, Bobby Ghassemi was well enough to attend his high school graduation.
"The whole place was cheering for me, and they all stood up and were screaming and cheering my name," Ghassemi, now 20, recalls with a smile. "I took my graduation cap off and waved it around."

He still has significant left-side weakness and is relearning how to walk, but his progress has been tremendous, according to Lewis.

"In my opinion, and this is pure speculation, he never would have come out of a coma if it hadn't been for the use of omega-3s to allow that natural healing process to occur," said Lewis, founder of the Brain Health Education and Research Institute. "In the end, the brain has to heal itself. There are no magic cures for brain injury."

Large-scale study needed
But what do these two dramatic stories really say about omega-3 as a potential treatment for traumatic brain injury? For now, they are merely stories with omega-3 as a common denominator.

The remaining questions are as poignant as the stories themselves: Could youth have been a factor for Ghassemi and McCloy? What about other treatments given to McCloy, like hyperbaric oxygen? Could they have played a role?

Those and other questions could and should be answered, according to experts, with a large-scale clinical study.
"These two clinical cases where we have a wildly unexpected recovery, was it just luck that they woke up?" asked Dr. Joseph Hibbeln, an omega-3 expert and chief of the Section on Nutritional Neurosciences at the National Institutes of Alcohol Abuse and Alcoholism. "Or is there some reasonable scientific explanation for it?
"Given that there aren't any other treatments, this is a good bet," Hibbeln said. "It's really only reasonable to go forward with doing the full press of careful intervention studies."

The implications of a successful study are huge: 1.7 million people suffer a traumatic brain injury each year in the United States.

And research into how omega-3 might function for stroke, Parkinson's disease and early Alzheimer's disease is ongoing.

"The message that I'm trying to get across is, there's more you can do," Lewis said. "If you add omega-3s, we can then begin to let the brain heal itself a little more efficiently."

"Up until the time the pharmaceutical industry gives us a drug that cures all brain injury, this is the best hope we have," Bailes said.

High-carb diet may impair brain function

Older people who load up their plates with carbohydrates have nearly four times the risk of developing mild cognitive impairment, a new study finds.

Sugars also played a role in the development of MCI, which is often a precursor to Alzheimer’s disease, says the report in the newest Journal of Alzheimer’s Disease. Eating more proteins and fats offers some protection from MCI.

Mayo Clinic researchers tracked 1,230 people ages 70 to 89 and asked them to provide information on what they ate the previous year. Among that group, only the 940 people who showed no signs of cognitive impairment were asked to return for follow-ups every 15 months.

By the study’s fourth year, 200 of the 940 were beginning to show mild cognitive impairment — problems with memory, language, thinking and judgment. Compared with people who rank in the bottom 20 percent for carbohydrate consumption, those in the highest 20 percent had a 3.68 times greater risk of MCI, the study found. Overall, about six in every 100 people develop MCI in their lifetime.

Not everyone with MCI develops Alzheimer’s disease, but many do, says lead author Rosebud Roberts, a professor in the department of epidemiology at the Mayo Clinic in Rochester, Minn. Alzheimer’s affects 5.2 million U.S. adults, numbers that are expected to triple by 2050.

“If we can stop people from developing MCI, we hope we can stop people from developing dementia. Once you hit the dementia stage, it’s irreversible,” says Roberts.

Among foods regarded as complex carbohydrates: rice, pasta, bread and cereals. The digestive system turns them into sugars. Fruits, vegetables and milk products are simple carbs.

“A high-carbohydrate intake could be bad for you because carbohydrates impact your glucose and insulin metabolism,” says Roberts. “Sugar fuels the brain, so moderate intake is good. However, high levels of sugar may actually prevent the brain from using the sugar — similar to what we see with type 2 diabetes.”

Roberts says high glucose levels might affect the brain’s blood vessels and play a role in the development of beta amyloid plaques, proteins toxic to brain health that are found in the brains of people with Alzheimer’s. Researchers don’t know what causes the disease, but they suspect the buildup of beta amyloid is a leading cause.

Also among the study’s findings:

Those whose diets were highest in fat (nuts, healthy oils) were 42 percent less likely to get cognitive impairment, while those who had the highest intake of protein (chicken, meat, fish) had a reduced risk of 21 percent.

Several popular diets, including the Mediterranean (fish, poultry-based protein; plenty of plant-based foods and healthy fats) and Atkins (low-carb, meat-lover’s diet), make pitches for the multiple health benefits from lowering carb intake, including reduced risk for heart disease and diabetes, and improved brain health.

Eric Westman of Duke University Health System, who is author of The New Atkins for a New You, called this “a provocative, preliminary study that suggests that we can add the loss of mental function in older age to the list of medical problems caused by excessive carbohydrate consumption. This is not proof that a low-carb diet will fix dementia, but it is a good argument for conducting studies to determine if it can.”

Roberts says the study offers hope because “it shows a modifiable way we can reduce risk for the disease. It is important to eat a balance of protein, carbohydrates and fat.”

Why brain tumors are so hard to destroy

The most common and aggressive brain tumor grows by turning normal brain cells into stem cells, which can continuously replicate and regrow a tumor with only a handful of cells left behind, new research finds.

The findings help explain why the tumors, called glioblastomas, are so difficult to treat, said study researcher Inder Verma, a molecular biologist at The Salk Institute in California. Even the surgical removal of a tumor may not be able to extract every single cancerous cell, Verma told LiveScience.

Glioblastomas "reoccur because every cell that is left behind has the ability to start all over again," Verma said.
Aggressive tumors
Glioblastoma multiforme tumors make up the majority of brain tumor cases and have a very poor prognosis. According to a 2010 study in CA: A Cancer Journal for Clinicians, the average survival rate after a glioblastoma diagnosis is 14 months (though improving surgical techniques had boosted that number from 10 months in only five years prior to the study).

Verma and his colleagues were interested in finding a more accurate way of studying tumor growth. Most mice studies of cancer introduce human tumor cells into mice with no immune systems or genetically engineer mice so that every cell is cancer-prone. But that's not how tumors arise in real life, Verma said. He and his co-researchers wanted to find a way to mimic cancer's growth from a single cell to out-of-control.

Using viruses, they introduced cancer-causing genes into mice, developing a technique in which as few as 20 cancerous cells can trigger tumor growth. They then found that a mere 10 cells from one of these mouse tumors, transplanted into a healthy mouse, could lead to a whole new tumor in that mouse. [Colorful But Deadly: Images of Brain Cancer]

"That suggested that every cell in these tumors or glioblastomas has the ability to make new glioblastomas," Verma said.

Stem cell switch
Researchers once believed that glioblastomas arose only from glial cells, the "support" cells in the brain that surround neurons. When it was discovered that the brain contains stem cells, which are capable of transforming into any sort of neural tissue, researchers figured cancer could arise from those cells, too, said study researcher Dinorah Friedmann-Morvinski, also a Salk Institute researcher.

But now, Friedmann-Morvinski, Verma and their colleagues have found they can coax even neurons into cancer cells by introducing cancer-causing genes. The neurons, which should not be able to divide and reproduce anymore, turn back into stem cells, which can continuously divide.

Researchers have successfully reprogrammed cells into stem cells in the lab, a feat that earned scientists John B. Gurdon and Shinya Yamanaka the 2012 Nobel Prize in Medicine. It was surprising, still, to find the cancer cells performing this trick, Friedmann-Morvinski told LiveScience, but there were "some hints it might be happening."

The next step, the researchers said, is to learn more about how the cells revert into stem cells and then find a way to block the out-of-control growth of these cancerous cells.

"You have to kill them in order to kill the tumor in the long run," Verma said.

How the brain perceives direction and location

London, October 20 (ANI): In a new study, researchers are investigating nerve cells in the brain that function in establishing one's location and direction.

Dartmouth neurobiologist Jeffrey Taube is using microelectrodes to record the activity of cells in a rat's brain that make possible spatial navigation -how the rat gets from one place to another - from "here" to "there."
But before embarking to go "there," you must first define "here."

"Knowing what direction you are facing, where you are, and how to navigate are really fundamental to your survival," Taube said. 

"For any animal that is preyed upon, you'd better know where your hole in the ground is and how you are going to get there quickly. And you also need to know direction and location to find food resources, water resources, and the like," he said,

Not only is this information fundamental to your survival, but knowing your spatial orientation at a given moment is important in other ways, as well. 

Taube points out that it is a sense or skill that you tend to take for granted, which you subconsciously keep track of. 

"It only comes to your attention when something goes wrong, like when you look for your car at the end of the day and you can't find it in the parking lot," Taube said.

Perhaps this is a momentary lapse, a minor navigational error, but it might also be the result of brain damage due to trauma or a stroke, or it might even be attributable to the onset of a disease such as Alzheimer's.
Understanding the process of spatial navigation and knowing its relevant areas in the brain may be crucial to dealing with such situations.

One critical component involved in this process is the set of neurons called "head direction cells."
These cells act like a compass based on the direction your head is facing. They are located in the thalamus, a structure that sits on top of the brainstem, near the centre of the brain.

He is also studying neurons he calls "place cells." These cells work to establish your location relative to some landmarks or cues in the environment. 

The place cells are found in the hippocampus, part of the brain's temporal lobe. They fire based not on the direction you are facing, but on where you are located.

Studies were conducted using implanted microelectrodes that enabled the monitoring of electrical activity as these different cell types fired.

Taube explains that the two populations - the head direction cells and the place cells - talk to one another.
"They put that information together to give you an overall sense of 'here,' location wise and direction wise," he said.

"That is the first ingredient for being able to ask the question, 'How am I going to get to point B if I am at point A?' It is the starting point on the cognitive map," Taube said.

Taube and Stephane Valerio, his postdoctoral associate for the last four years, have just published a paper in the journal Nature Neuroscience, highlighting the head direction cells. 

The studies described in Nature Neuroscience discuss the responses of the spatial navigation system when an animal makes an error and arrives at a destination other than the one targeted - its home refuge, in this case. 

The authors describe two error-correction processes that may be called into play - resetting and remapping - differentiating them based on the size of error the animal makes when performing the task.

When the animal makes a small error and misses the target by a little, the cells will reset to their original setting, fixing on landmarks it can identify in its landscape. 

"We concluded that this was an active behavioural correction process, an adjustment in performance," Taube said.

"However, if the animal becomes disoriented and makes a large error in its quest for home, it will construct an entirely new cognitive map with a permanent shift in the directional firing pattern of the head direction cells," he said.

This is the "remapping."

The study has been published in Nature Neuroscience.

Brain-eating amoeba

PHYSICIANS M. Fowler and R.F. Carter first described human disease caused by amoebo flagellates in Australia in 1965. Their work on amoebo flagellates has provided an example of how a protozoan can effectively live both freely in the environment and in a human host. 

Since 1965 more than 144 cases have been confirmed in a variety of countries. In 1966 Fowler termed the infection resulting from N. fowleri primary amoebic meningoencephalitis (Pam) to distinguish this central nervous system (CNS) invasion from other secondary invasions caused by other true amoebas such as entamoeba histolytica.

A retrospective study determined the first documented case of Pam possibly occurred in Britain in 1909. Onset symptoms of infection start about five days (range is from one to seven days) after exposure.

The initial symptoms include, but are not limited to, changes in taste and smell, headache, fever, nausea, vomiting and stiff neck. Secondary symptoms include confusion, hallucinations, lack of attention, ataxia, and seizures. After the start of symptoms, the disease progresses rapidly over three to seven days, with death occurring from seven to 14 days after exposure.

Countries where cases of amoebia are found are the US, Chezk Republic, New Zealand, Pakistan and the UK. It is a universal issue. International organisations must get together to find out its solution to save human lives.

When the brain refuses to take the hint

Many misconceptions about MS... Photo: K.R. Deepak
The Hindu Many misconceptions about MS...

Multiple Sclerosis (MS) is a disease of the brain and spinal cord marked by loss of balance, vision loss, weakness of limbs, and bladder dysfunction among other symptoms. However, it often goes 
undiagnosed, leading to delay in treatment. It affects women more than men. The disorder is commonly diagnosed between 20 and 40 years but can be seen at any age. 

MS is caused by damage to the myelin sheath, the protective covering that surrounds nerve cells. Due to damage in the nerve layer, transmission of signals from the brain and spinal cord is affected. 

Due to certain myths and misconceptions, many people do not come out in the open to get themselves diagnosed and treated. Multiple Sclerosis is stereotypically believed to be a disease that is fatal, contagious, genetic, that can’t be treated, and that every patient ends up in a wheelchair. 

According to research, most people with MS have a normal life expectancy and it is not contagious or infectious. As for the fear of ending up in a wheelchair, most MS patients do not require a wheelchair if diagnosed early. At the same time, the use of mobility devices is just a way of providing independence and relief from fatigue and other symptoms. The fear of MS being a genetic disease can easily be explained by the fact that, even though people with relatives who have MS have a slightly higher chance of getting it, there is no genetic certainty. 

The last decade has seen the development of disease-modifying therapies (DMTs) to treat MS. These therapies directly affect the underlying process in relapsing-remitting MS. The physician will determine the best DMT course depending upon various factors. An accurate diagnosis of multiple sclerosis is based on the combination of clinical features, cerebrospinal MR imaging, neurophysiological and laboratory tests.

Therapy matters

MS may be a chronic debilitating disease but it can be managed with proper care. Alternative therapies such as physical therapy, speech therapy and occupational therapy help manage the symptoms. 

While researchers are working to develop new treatments for different stages of MS, several other forms of treatments are being undertaken. The problem, though, is that these are untested and cannot be recommended safely. Take stem cell treatment, for example. It may be a reality in the future but is now used only for research. Even though technologically advanced, stem cell treatments pose the threat of uncontrollable growth in the stem cells leading to tumors. 

Need for awareness

As a result these treatments may be said to take undue advantage of the patient’s desperation. Also what is needed is much higher awareness among patients about these treatments.

MS is largely incurable; but there are several ways of improving the patients’ life. In case of MS, the patients must avoid stress at any cost. Other factors that can worsen symptoms include over exposure to sun and steam baths. Increased body temperature can temporarily make the symptoms worse by causing the nerves affected by MS to function even more poorly.

Many patients with MS understand these arguments but still insist on going ahead with banned or non-viable procedures like “liberation therapy” and “stem cell therapy”. They can hardly be blamed as they fear ongoing loss of function and premature death. 

Leading a healthy lifestyle and paying heed to the suggestions of experts is recommended. Health decisions should not be based on hope and desperation but should be rational and practical. 


Muscular: Unable to balance, numbness or tingling or pain in any part of the body, unable to move arms/legs properly or coordinate movement,  muscular spasms, tremor or weakness in limbs.

Bowel and bladder: Constipation, inability to control bowels, difficulty urinating or frequent need/strong urge to urinate.

Eye: Uncontrollable rapid eye movement, double vision, discomfort, and vision loss.

Sexual: Decreased sexual drive, problem with erections, ejaculation or vaginal lubrication.

Patients, families help direct groundbreaking brain research

WILLIAM SUAREZ/HOLLAND BLOORVIEW Holland Bloorview patient Corvin shows Dr. Tom Chau his favourite computer game in 2009. Dr. Chau and his team had developed a customized communication switch to allow Corvin to access a computer.

Two years ago, a 26-year-old man with severe spastic quadriplegic cerebral palsy communicated with the outside world for the first time.

Tom Chau, vice-president of research at Holland Bloorview, and his team had spent months training him how to use the heat from his mouth, one of the only parts of his body that he could control, by opening and closing it.

These signals, when linked to an infrared thermographic switch, allowed the man to type his first word.

“M-U-T-H—,” he wrote.

“Mouth,” a research assistant in the room said, according to Chau. “Are you typing, ‘Mouth?' ”
“ — E-R,” he finished.

“He typed ‘Mother,' ” Chau recalls. “He typed ‘Mother.' ”

Chau says it is stories like these that motivate him in his work. There are 18 scientists at Holland Bloorview’s Research Institute, with four focusing on three to four different groundbreaking, brain-related research initiatives at any given time. It sounds like a lot, but Chau says resources are limited and they have to be choosy about what projects to take on.

Since children and their families at the hospital act as research subjects, Chau says it's often their input that informs the direction research takes.

In addition to Chau's work in brain computer interfacing, scientist Darcy Fehlings studies neuro-reorganization, which focuses on the rehabilitation of children with congenital brain disorders; Michelle Keightley is investigating the neuro-rehabilitation of kids with acquired brain injuries; and clinician-scientist Evdokia Anagnostou is a child neurologist and the co-lead of the Autism Research Centre at Holland Bloorview, which opened in 2011.

“Here, we believe that understanding the biology will lead to treatment,” Anagnostou says. “If we don't understand what the biological problem is, then our attempts for therapeutics are very modest.”

The centre is tapped into global autism spectrum disorder (ASD) research, and scientists communicate with the scientific community and the Holland-Bloorview community to decide what initiatives to take on.

Recently, Anagnostou studied oxytocin hormone levels. In women, the hormone is important for producing breast milk and during labour and delivery. But when the oxytocin gene in male and female animals was removed, the animals lost aspects of their social function.

Anagnostou is applying these findings to kids with ASD in the hope that by manipulating their oxytocin levels she can improve their social interactions.

In another Holland Bloorview study, the ratio of chemicals in the brain associated with excitability and calmness are manipulated with Riluzole, a drug used to treat amyotrophic lateral sclerosis (ALS), more commonly known as Lou Gehrig's disease. Scientists believe that there may be an imbalance in this chemical ratio in the brains of kids with ASD, making it difficult for them to filter out what most people consider “noise” or insignificant information.

There are already therapeutics that patients benefit from at Holland Bloorview, and the new 18-month well-baby visit, a program being rolled out by the Ontario government, could help pediatricians recognize the signs of autism or other issues at an early age. But in order for kids to benefit from the early diagnosis, they must receive treatment.

“The earlier we pick them up, the better the chances for outcomes,” Anagnostou says. “But do you know what the Toronto system for autism services is doing with early diagnoses? They put them on a waiting list until they're three.”

Keightley, a neurologist, studies acquired brain injuries, such as meningitis, vasculitis, stroke and concussions, which have become particularly topical with respect to professional sports.

Scientists have developed new “return-to-play” guidelines for adults who have suffered a concussion, stipulating a period of rest before they can play again. But there are no such evidence-based guidelines for children and youth.

“In the province of Ontario alone, there are probably 240,000 kids playing registered hockey. And we know that a conservative estimate of a concussion is 10 per cent,” says Keightley. “So that's 24,000 concussions happening every year in the sport of hockey alone.”

In one study, Keightley had kids wear a special helmet while they played hockey that recorded information about what parts of the head were hit. Scans of their brains were taken before and after games, in an effort to see if hits affected brain function. Results are pending.

Despite the exciting prospects in brain research at Holland Bloorview, Chau says one of the more challenging aspects is that there's always a chance participants won't benefit directly from their participation, nor is there any certainty that the experiment will work. And since children and families can commit themselves to studies for long periods of time, it can really test the resilience of researchers and their subjects. And, yet, according to Anagnostou, they never have any shortage of willing participants for the work they're doing.

“I have to say it has been impressive how willing Ontarians are to participate,” she says. “We haven't had to place a single ad in the newspaper yet for our study. They come.”

Mobile phone 'caused brain tumour' says Italy's top court

Mobile phone Compensation case: an Italian court has concluded that mobile phone use gave a businessman a benign brain tumour. 

ITALY'S top court has ruled a businessman's brain tumour was caused by regular mobile phone use so he deserves worker's compensation.

Innocente Marcolini, whose face is partially paralysed, argued that using mobile phones six hours a day for 12 years while dealing with clients in China and elsewhere overseas caused the tumour on the trigeminal nerve in his head.

His lawyers presented doctors who testified that excessive mobile phone use increases risk of such tumours.
The impact of the ruling earlier this week is unclear. Numerous large scientific studies have failed to find a causal link between cellphones and brain tumours.

The World Health Organisation classifies mobile phones as "possible" carcinogens, in the same category as pesticides and coffee.

Thursday, October 18, 2012

Inside the Brain: A Journey Through Time

The Human Brain
The brain has long boggled the mind with its complexity, which is probably best summed up by Carl Sagan in "The Cosmos," when he said, "The brain is a very big place in a very small space." With modern technology, scientists are peering deeper and closer than ever before at the tangle of neurons and their billions of connections. Here's a peek at what the brain looks like, from antiquity to present-day.

Portraits of the Mind
In the book, "Portraits of the Mind: Visualizing the Brain from Antiquity to the 21st Century" (Abrams 2010), astonishing images that reveal both the complexity and beauty of the brain. And through time as brain-imaging technology comes online, scientists have new ways of seeing and interpreting the brain. Check out some of the amazing photos from the book.

Canine Scents
This 1875 drawing showing a dog's olfactory bulb was completed using a staining method named after Camillo Golgi in which certain chemicals are injected into nervous tissue so they can be seen. Some say its application to the study of brain tissue represents the beginning of modern neuroscience.

Dripping Dendrites
While all cells in the body hold the same genome, only a particular set of its genes get turned on in various cells; each type of neuron switches on a gene set that defines its character.
In this picture, a gene called JAM-B had been switched on, which then turned on a fluorescent protein to reveal a small group of brain cells. The resulting image shows that all of the neurons' projections called dendrites are aligned in the same direction; moreover, these retinal neurons are known to detect only objects moving in an upward direction.

Baroque Blood Vessels
A scanning electron microscope (SEM) image zooms in on the baroque branching structures that send blood to the human brain's cortex. The vessels are organized such that the large blood vessels surround the surface of the brain (top of image), sending thin, dense projections down into the depths of the cortex (bottom of image).

View of a StrokeCredit
A brain-imaging method called diffusion MRI (magnetic resonance imaging) is relatively new to the field of neuroscience, though it shows promise as a diagnostic tool. Here, an image taken from the brain of a patient who suffered a stroke in the thalamus and midbrain, resulting in damage to certain axons (some are visible at the bottom of the image).

Mouse BrainCredit
A cross-section of a mouse's hippocampus — one of the brain's memory centers — reveals its intricate network of neurons, whose soma are shown as small circles. The hippocampus is seen here nestled directly beneath the neocortex, which is the outer layer of the cerebral hemispheres.

Spiny NeuronCredit
Most neurons have three parts: an axon, a cell body called a soma and dendrites. This scanning electron microscope (SEM) image shows a soma with dendrites (and their spines) radiating from it. To create SEM images, a beam of electrons is scanned across the surface of a sample, and a detector keeps track of electrons bouncing off its surface to reveal the specimen's outer shape.

Artsy Brain CellsCredit
Here, two types of cells in the cerebellum are shown: glia and Purkinje neurons. The cells can be distinguished because of a method that relies on the body's immune system and its antibodies — proteins that recognize and latch onto "foreign substances." Biologists now use antibodies to reveal where certain proteins are found in the brain. Here, red is an antibody staining of a protein that's found in glia cells, while green reveals a protein called IP3, of which Purkinje neurons are chockfull.

Color My Cerebellum The colored splotches reveal so-called presynaptic terminals, or junctions through which neuron signals are sent, formed by the cerebellum's axons.

While Golgi's staining method did wonders for finding structures hidden in a tangle of neurons, it couldn't distinguish individual brain cells that were illuminated in the same color.
Enter a bit of genetic trickery called Brainbow: Robert Tsien and other chemists tinkered with and discovered fluorescent proteins responsible for the different colors emitted by various sea creatures (such as corals and jellyfish). By coaxing different sets of neurons or even different individuals of a species (say a male and female) to express different proteins, scientists could pick out the cells by the color they glowed.
Here, several motor-neuron axons (slender projections on neurons that transmit signals to other neurons) travel side by side as they lead to the muscles whose contractions they regulate.

Studies Reveal How Diet Affects Brain Functions

TEHRAN (FNA)- Studies released recently explored the neurological component of dietary disorders, uncovering evidence that the brain's biological mechanisms may contribute to significant public health challenges - obesity, diabetes, binge eating, and the allure of the high-calorie meal. 
The findings were presented at Neuroscience 2012, the annual meeting of the Society for Neuroscience and the world's largest source of emerging news about brain science and health.

Scientists are ultimately searching for new ways to treat diet-related disorders while raising awareness that diet and obesity affect mental as well as physical health.

Today's new findings show that:

Being obese appears to affect cognitive function, requiring more effort to complete a complex decision-making task (Timothy Verstynen, PhD, abstract 802.20).

Brain images suggest that when people skip breakfast, the pleasure-seeking part of the brain is activated by pictures of high-calorie food. Skipping breakfast also appears to increase food consumption at lunch, possibly casting doubt on the use of fasting as an approach to diet control (Tony Goldstone, MD, PhD, abstract 798.02).

A study in rats suggests they may be able to curb binge-eating behavior with medication used to keep substance abusers clean and sober (Angelo Blasio, PhD, abstract 283.03).

Other recent findings discussed show that:

Amidst growing concern that diet-related metabolic disorders such as diabetes impair brain function, an animal study reports that a high-sugar diet may affect insulin receptors in the brain and dull spatial learning and memory skills. But omega-3 supplements may at least partially offset this effect (Rahul Agrawal, PhD).

Evidence from a rat study suggests that a new compound under development to treat compulsive eating disorders and obesity may be effective at blocking a specific receptor in the brain that triggers food cravings and eating when activated by "food related cues," such as pictures or smells, irrespective of the body's energy needs (Chiara Giuliano, PhD).

"These are fascinating studies because they show the brain is an often overlooked yet significant organ in an array of dietary disorders," said press conference moderator Paul Kenny, PhD, of The Scripps Research Institute in Florida, an expert on addiction and obesity. "Many of these findings have the potential to lead to new interventions that can help reduce the ranks of the obese, helping those who struggle daily with dietary decisions reassert control over what they eat."

This research was supported by national funding agencies such as the National Institutes of Health, as well as private and philanthropic organizations.

Dolphins stay awake for 15 days by sleeping with one half of brain

Dolphins can stay alert and active for 15 days or more by sleeping with one half of their brain at a time, scientists have learned.

Dolohins can stay away for up to 15 days by sleeping with one half of their brain at a time
Dolohins can stay away for up to 15 days by sleeping with one half of their brain at a time
Dolphins can stay alert and active for 15 days or more by sleeping with one half of their brain at a time, scientists have learned.
The trick of keeping half the brain continuously awake is vital to the sea mammals' survival, experts believe.
It allows them to come to the surface every so often to breath, and remain constantly vigilant for sharks.
Scientists in California, US, tested the ability of two bottlenose dolphins to echolocate accurately over periods of time which would have left other animals sleep-deprived and exhausted.
The dolphins, a male called Nay and female called Say, had to swim around a pen looking for phantom sonar targets.

Each of the eight targets consisted of a device that picked up dolphin sound pulses and sent back ''phantom'' echoes.

When a dolphin detected an echo from an activated target, it responded by pressing a paddle. Correct detection triggered a tone, signalling success, and the dolphin was rewarded with a fish. False alarms led to no tone and no reward.

Over three sessions of five continuous days both dolphins did well, with success rates of up to 99%, but Say outperformed her male partner.

The scientists then went on to test Say further by repeating the same experiment over a period of 30 days. In the event, a storm cut the trial short after 15 days had elapsed. However, during this time Say's performance hardly deteriorated at all.

The findings were published yesterday in the online journal Public Library of Science ONE.

Lead researcher Dr Brian Branstetter, from the National Marine Mammal Foundation in San Diego, said: ''These majestic beasts are true unwavering sentinels of the sea. The demands of ocean life on air breathing dolphins have led to incredible capabilities, one of which is the ability to continuously, perhaps indefinitely, maintain vigilant behaviour through echolocation.''

The difference in performance between Nay and Say was probably down to personality, said the scientists.
Say appeared much more motivated and keen on the task, often producing ''victory squeals'' when she correctly responded to a target.

Dolphins use their sonar-like ability to navigate, find prey, detect predators, and co-ordinate group behaviour.

Brain wave measurements have confirmed that the creatures are capable of ''unihemispheric sleep'' - sleeping with just one side of the brain. When dolphins sleep in this way, they often keep one eye open.
Many dolphin populations are exposed to almost constant risk of shark attack, and the animals commonly carry bite marks, said the researchers. Continually listening to their echo signals allowed them to counter the shark threat, even in murky waters.

The scientists wrote: ''From an anthropomorphic viewpoint, the ability of the dolphin to continuously monitor its environment for days without interruption seems extreme.

''However, the biological, sensory and cognitive ecology of these animals is relatively unique and demanding. If dolphins sleep like terrestrial animals, they might drown. If dolphins fail to maintain vigilance, they become susceptible to predation. As a result, the apparent 'extreme' capabilities these animals possess are likely to be quite normal, unspectacular, and necessary for survival from the dolphin's perspective.''

Scientists discover how brain erases unwanted memories

Scientists have discovered that brain can help us voluntarily forget unwanted memories by either blocking them out or substituting them.

Researchers from the Cambridge University tested if suppressing memories or substituting them with more desirable memories could erase them and whether these tactics could engage distinct neural pathways.

To test this possibility, researchers used functional magnetic resonance imaging to examine the brain activity of volunteers who had learned associations between pairs of words and subsequently attempted to forget these memories by either blocking them out or recalling substitute memories.
Although the strategies were equally effective, they activated distinct neural circuits. During memory suppression, a brain structure called dorsolateral prefrontal cortex inhibited activity in the hippocampus, a region critical for recalling past events. On the other hand, memory substitution was supported by caudal prefrontal cortex and midventrolateral prefrontal cortex - two regions involved in bringing specific memories into awareness in the presence of distracting memories.
"This study is the first demonstration of two distinct mechanisms that cause such forgetting: one by shutting down the remembering system, and the other by facilitating the remembering system to occupy awareness with a substitute memory," said lead study author Roland Benoit.
"A better understanding of these mechanisms and how they break down may ultimately help understanding disorders that are characterised by a deficient regulation of memories, such as posttraumatic stress disorder," Benoit said in a statement.
"Knowing that distinct processes contribute to forgetting may be helpful, because people may naturally be better at one approach or the other," he said.

Training the brain to stress less

Neurotopia recently began beta-testing a dry sensor, mobile headphone and tablet system that would map brain waves.Neurotopia recently began beta-testing a dry sensor, mobile headphone and tablet system that would map brain waves

Editor's note: CNN contributor Amanda Enayati ponders the theme of seeking serenity: the quest for well-being and life balance in stressful times. She delivered a version of this piece as a talk at Stanford's Medicine X conference last week.
(CNN) -- Train the brain. Until recently, this phrase made me picture Neo from "The Matrix" proclaiming "I know kung fu" after he had martial arts abilities uploaded into his brain.

But what if we really could harness technology, Neo-style, to help train our brains to better cope with everyday stress?
For many of us, the days seem to pass in one anxiety-ridden blur after another. Mental health professional increasingly agree that these daily sprints, accompanied by a soundtrack of endless beeps, chirps and vibrations emitting from various devices, set off our stress systems, keeping us in a persistent and physiologically damaging state of fight-or-flight.
"The way we live our lives now is like running marathons," said Dr. Leslie Sherlin, a neuroscientist and chief science officer of Neurotopia, a company that provides brain training to athletes. "And in some ways, that's great, but you can't run marathons all the time."
Keep that pace, says Sherlin, and at some point, you will burn out. You may also suffer from a weakened immune system that can lead to an increased risk of disease.
Most of us have received some kind of formal instruction about diet, exercise, the birds and the bees. So why aren't we training our brains to better manage stress?
Some of the most compelling training to help prepare people to better handle stress is going on right now with athletes and soldiers.
For these two distinct groups, performance under high stress is a must (albeit for very different reasons). But the technologies being used to train them could benefit the rest of us as well.
Technology could help us reduce stress, too
Training athletes for the field
I became interested in the way athletes train for peak performance in high-stakes environments last year, when I interviewed Michael Gervais, a sports psychologist who works with Sherlin to train elite athletes to perform optimally during high-stress competition. Gervais and Sherlin work with athletes from the NFL, NBA and NHL as well as Olympians, golfers and many others.
What Gervais told me then was that the key to high performance was a disciplined mind. While not exactly news, the methods Gervais and his colleagues use to teach mental discipline were quite interesting. They were using older Eastern disciplines like mindfulness, presence, meditation, deep breathing and neurofeedback.
The way we live our lives now is like running marathons. ... In some ways, that's great, but you can't run marathons all the time.   Dr. Leslie Sherlin, chief science officer of Neurotopia
As part of their training, Gervais and his colleagues hook up athletes to electrodes and perform a baseline qEEG: a quantitative electroencephalogram. They use the results to create an individualized brain map.
The map helps these sports psychologists assess and quantify mental aspects of performance like focus, decision speed, reaction time and stress regulation.
Once the brain is mapped, the psychologists conduct half-hour neurofeedback sessions to teach athletes how to reach optimal brain wave patterns. In a typical session, the athlete will sit before a large screen as sensors monitoring electrical activity in his or her brain are placed on the scalp.
The athlete then focuses on achieving desirable brain wave patterns that, in turn, influence what happens on the screen. It's bit like controlling a video game with only your thoughts. The version I saw involved cars racing through a desert.
The training is meant to teach athletes how to respond quickly to stressor stimuli, how to focus during stressful situations, how to recover from errors and finally how to shut down and still their minds when it's all over.
These sports psychologists have collected a proprietary brain bank of assessments over years of working with elite athletes. They use the brain bank to identify optimal brainwave patterns associated with the highest levels of performance.
According to Sherlin, it takes roughly 15 to 20 neurofeedback sessions for elite athletes to learn some of these techniques. (Probably about 30 for you and me, he says.)
Your questions about stress, answered! 
Originally developed as a technique to measure brain activity in NASA pilots during flight simulation exercises, neurofeedback has shown promising initial results for helping retrain the brainwaves of children with ADHD and autism and people suffering from chronic migraines. In one study, student eye surgeons were trained to significantly improve their surgical skills by regulating their own brainwave activity.
The method is being examined in a diverse number of other contexts, including to help relieve symptoms of chemotherapy-induced nerve damage. Controlled, randomized trials will help validate these promising starts.
The kind of training that the athletes working with Gervais and Sherlin receive is not available to most of us right now, but it may be in our near future.
A few weeks ago, Sherlin's company, Neurotopia, began beta-testing a dry (no goo in your hair) sensor, mobile headphone and tablet system that purports to do the same kind of assessment and training as the older model. At least in theory, this might make the product accessible to the rest of us.
Training soldiers for the battlefield
A conversation with Dr. Albert "Skip" Rizzo, psychologist and research professor at the University of Southern California Keck School of Medicine, is like a lesson in applied science fiction, with your mind reeling from "Star Trek" to the original "Total Recall."
Except Rizzo's jaw-dropping efforts are not fiction, nor are they "on the horizon." They are here, now.
In a collaboration between the military, Hollywood and USC's Institute for Creative Technologies, where he serves as the associate director for medical virtual reality, Rizzo and his colleagues have developed cutting-edge gaming and virtual reality technologies to serve the clinical needs of soldiers.
Virtual Iraq (and Afghanistan) are based on exposure therapy, which has been effective in the treatment of PTSD.
Virtual Iraq (and Afghanistan) are based on exposure therapy, which has been effective in the treatment of PTSD.
One project, Stress Resilience in Virtual Environments (STRIVE), helps train service members to have better resilience and emotional coping skills in realistic virtual-reality combat scenarios before they are exposed to the real stresses of combat.
A second project, called Virtual Iraq (there is also a Virtual Afghanistan), helps soldiers returning from combat work through their trauma by donning a helmet geared with video goggles, earphones and a scent machine, and revisiting the scene in a virtual reality setting, complete with sound and smell. Both STRIVE and Virtual Iraq (and Afghanistan) are based on exposure therapy, which has been effective in the treatment of post-traumatic stress disorder.
The problem with PTSD is that the person often avoids anything that reminds them of the trauma, and this avoidance begins to generalize to everyday things, says Rizzo.
"It's a snowball cascade effect. The things that evoke the fear and anxiety are no longer directly tied to the original trauma but generalized to the outside world. You see people with PTSD who will no longer leave their house, and if they do, they're a nervous wreck."
The idea, says Rizzo, is to re-create the stressful environment in a doctor's office, to help the patients confront and challenge the trauma and to give them the tools to better cope emotionally with what happened.
Both of these technologies require specialists and a clinical setting, but SimCoach, a "virtual human" designed for interactive use on the Internet, does not.
Though at this point, SimCoach is targeted toward active-duty military personnel, veterans and their families, it may also have wider utility for everyday stress and anxiety.
SimCoach users can select one of several avatars to talk to when they are feeling stressed out. The virtual human coaches can serve as an "online companion for anyone who may be too introverted to seek help, someone who may not want to reach out to a clinician or who may feel stigma about seeing a therapist," said John Hart, program manager at the Institute for Creative Technologies.
SimCoach users can select one of several avatars to talk to when they are feeling stressed out
SimCoach users can select one of several avatars to talk to when they are feeling stressed out
"SimCoach is not a doc-in-the-box, and it's not going to make a diagnosis," Hart observed. Nor is it meant to replace human interaction.
What SimCoach does do is help those suffering from stress and anxiety symptoms begin the conversation about what they may be going through. It may also provide users with more information about what they may be experiencing, suggest local facilities where they can go for care and perhaps even walk them through breathing exercises or stress reduction techniques.
Hart summed up what I find most compelling about SimCoach: "Here we are, sitting on a mountain of valuable information about what to do when you're stressed or feeling depressed. You can see how SimCoach can help people access the right information when they need it."
Imagine the possibilities! An interactive virtual-reality source for information on stress, anxiety and PTSD -- the precursor, perhaps, to a real-life version of "Star Trek's" Emergency Medical Hologram Doctor.
Home sweet home
I recently attended a conference in Portugal. As I made my way through customs at Philadelphia International, a customs agent asked me what I did for a living.
"I write," I said, "mostly about stress."
He stared me down for few moments before saying in a low, gruff tone: "If you really want to understand stress, then you need to spend a day with us here."
And here's the thing: Regardless of what we do, most of us are feeling that same way about our runaway lives. The genie is out of the bottle, and there is little likelihood of us ever going back to a simpler time (if there ever was such a thing).
So, yes, let's discuss technology addiction, always being "on," tech fasting and the need to design devices and apps for greater serenity. But let's also consider how to harness some of these technologies to help us move easier in this new world, Neo-style.