June 13th
4:40 PM
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neurosciencestuff: Team Points to Brain’s ‘Dark Side’ as Key to Cocaine Addiction Scientists at The Scripps Research Institute (TSRI) have found evidence that an emotion-related brain region called the central amygdala—whose activity promotes feelings of malaise and unhappiness—plays a major role in sustaining cocaine addiction. In experiments with rats, the TSRI researchers found signs that cocaine-induced changes in this brain system contribute to anxiety-like behavior and other unpleasant symptoms of drug withdrawal—symptoms that typically drive an addict to keep using. When the researchers blocked specific brain receptors called kappa opioid receptors in this key anxiety-mediating brain region, the rats’ signs of addiction abated. “These receptors appear to be a good target for therapy,” said Marisa Roberto, associate professor in TSRI’s addiction research group, the Committee on the Neurobiology of Addictive Disorders. Roberto was the principal investigator for the study, which appears in the journal Biological Psychiatry. Carrot or Stick? In addition to its clinical implications, the finding represents an alternative to the pleasure-seeking, “positive” motivational circuitry that is traditionally emphasized in addiction. While changes in these pleasure-seeking brain networks may dominate the early period of drug use, scientists have been finding evidence of changes in the “negative” motivational circuitry as well—changes that move a person to take a drug not for its euphoric effects but for its (temporary) alleviation of the anxiety-ridden dysphoria of drug withdrawal. George F. Koob, chair of TSRI’s Committee on the Neurobiology of Addictive Disorders, has argued that these “dark side” brain changes mark the transition to a more persistent drug dependency. In a series of recent studies, TSRI researchers including Roberto and Koob have highlighted the role of one of these dark-side actors: the receptor for the stress hormone CRF. Found abundantly in the central amygdala, CRF receptors become persistently overactive there as drug use increases, and that overactivity helps account for the negative symptoms of drug withdrawal. The central amygdala also contains a high concentration of a class of neurotransmitters called dynorphins, which bind to kappa opioid receptors. Much like the CRF system, the dynorphin/kappa opioid system mediates negative, dysphoric feelings—and there have been hints from previous studies that CRF doesn’t work alone in producing such feelings during addiction. “Our hypothesis was that the dynorphin/kappa opioid receptor system in the central amygdala also becomes overactive with excessive cocaine use,” said Marsida Kallupi, first author of the paper, who was a postdoctoral research associate in Roberto’s laboratory at the time of the study. Such overactivity would be expected to arise as the brain struggles to maintain “reward homeostasis”—a middle-of-the-road balance between pleasure and displeasure—despite frequent drug-induced swerves toward euphoria. “Dynorphin possibly acts to balance the euphoric effects produced by other opioid systems during recreational drug use,” said Scott Edwards, who is a research associate in the Koob laboratory and a co-author of the study. Reducing Signs of Addiction When the TSRI researchers gave rats extended access to cocaine, the rats escalated their daily intake as many human users would. Sensitive electrophysiological measurements revealed signs of a persistent functional overactivity of the GABAergic system in the rats’ central amygdalae—which corresponds to an anxiety-like state in the animals. Probing with compounds that activate or block kappa opioid receptors, the scientists found signs that these receptors, like CRF receptors, do indeed help drive the central amygdala into overactivity during excessive cocaine use. When the researchers blocked the kappa opioid receptors, central amygdala overactivity was greatly reduced. The same kappa opioid receptor-blocking treatment (antagonist) also reduced two standard signs of addiction in cocaine-using rats—the escalating hyperactive behavior each time the drug is taken and the anxiety-like behavior during withdrawal. These results give Roberto and her colleagues hope that a similar treatment might help human cocaine addicts feel less compelled to keep using. Kappa opioid receptor blockers are already being developed for the treatment of depression and anxiety. Blocking negative-motivational factors such as the kappa opioid and CRF systems also has the potential advantage that it spares the positive motivational pathways—the targets of older addiction therapies such as naltrexone. “We need to keep our positive motivational pathways intact so that they can signal the many normal rewarding events in our lives,” said Roberto. By contrast, she suspects, our negative motivational pathways involving CRF and kappa opioid receptors become abnormally active only in disease states such as addiction, and thus may be blocked more safely.

neurosciencestuff:

Team Points to Brain’s ‘Dark Side’ as Key to Cocaine Addiction

Scientists at The Scripps Research Institute (TSRI) have found evidence that an emotion-related brain region called the central amygdala—whose activity promotes feelings of malaise and unhappiness—plays a major role in sustaining cocaine addiction.

In experiments with rats, the TSRI researchers found signs that cocaine-induced changes in this brain system contribute to anxiety-like behavior and other unpleasant symptoms of drug withdrawal—symptoms that typically drive an addict to keep using. When the researchers blocked specific brain receptors called kappa opioid receptors in this key anxiety-mediating brain region, the rats’ signs of addiction abated.

“These receptors appear to be a good target for therapy,” said Marisa Roberto, associate professor in TSRI’s addiction research group, the Committee on the Neurobiology of Addictive Disorders. Roberto was the principal investigator for the study, which appears in the journal Biological Psychiatry.

Carrot or Stick?

In addition to its clinical implications, the finding represents an alternative to the pleasure-seeking, “positive” motivational circuitry that is traditionally emphasized in addiction.

While changes in these pleasure-seeking brain networks may dominate the early period of drug use, scientists have been finding evidence of changes in the “negative” motivational circuitry as well—changes that move a person to take a drug not for its euphoric effects but for its (temporary) alleviation of the anxiety-ridden dysphoria of drug withdrawal. George F. Koob, chair of TSRI’s Committee on the Neurobiology of Addictive Disorders, has argued that these “dark side” brain changes mark the transition to a more persistent drug dependency.

In a series of recent studies, TSRI researchers including Roberto and Koob have highlighted the role of one of these dark-side actors: the receptor for the stress hormone CRF. Found abundantly in the central amygdala, CRF receptors become persistently overactive there as drug use increases, and that overactivity helps account for the negative symptoms of drug withdrawal.

The central amygdala also contains a high concentration of a class of neurotransmitters called dynorphins, which bind to kappa opioid receptors. Much like the CRF system, the dynorphin/kappa opioid system mediates negative, dysphoric feelings—and there have been hints from previous studies that CRF doesn’t work alone in producing such feelings during addiction.

“Our hypothesis was that the dynorphin/kappa opioid receptor system in the central amygdala also becomes overactive with excessive cocaine use,” said Marsida Kallupi, first author of the paper, who was a postdoctoral research associate in Roberto’s laboratory at the time of the study.

Such overactivity would be expected to arise as the brain struggles to maintain “reward homeostasis”—a middle-of-the-road balance between pleasure and displeasure—despite frequent drug-induced swerves toward euphoria. “Dynorphin possibly acts to balance the euphoric effects produced by other opioid systems during recreational drug use,” said Scott Edwards, who is a research associate in the Koob laboratory and a co-author of the study.

Reducing Signs of Addiction

When the TSRI researchers gave rats extended access to cocaine, the rats escalated their daily intake as many human users would. Sensitive electrophysiological measurements revealed signs of a persistent functional overactivity of the GABAergic system in the rats’ central amygdalae—which corresponds to an anxiety-like state in the animals. Probing with compounds that activate or block kappa opioid receptors, the scientists found signs that these receptors, like CRF receptors, do indeed help drive the central amygdala into overactivity during excessive cocaine use.

When the researchers blocked the kappa opioid receptors, central amygdala overactivity was greatly reduced. The same kappa opioid receptor-blocking treatment (antagonist) also reduced two standard signs of addiction in cocaine-using rats—the escalating hyperactive behavior each time the drug is taken and the anxiety-like behavior during withdrawal.

These results give Roberto and her colleagues hope that a similar treatment might help human cocaine addicts feel less compelled to keep using. Kappa opioid receptor blockers are already being developed for the treatment of depression and anxiety.

Blocking negative-motivational factors such as the kappa opioid and CRF systems also has the potential advantage that it spares the positive motivational pathways—the targets of older addiction therapies such as naltrexone. “We need to keep our positive motivational pathways intact so that they can signal the many normal rewarding events in our lives,” said Roberto. By contrast, she suspects, our negative motivational pathways involving CRF and kappa opioid receptors become abnormally active only in disease states such as addiction, and thus may be blocked more safely.

#cocaine      #drugs      #cocaine addition      #psychology      #brain     
May 2nd
3:30 PM
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neurosciencestuff: Implanted device predicts oncoming seizures in those with epilepsy A new device may offer hope to people with epilepsy as the technology could predict the onset of seizures in adults who have the condition and can’t be treated with medication, according to Australian scientists. The small device is implanted in the brain. Researchers at the University of Melbourne said their proof-of-concept study found that it can successfully detect brain activity that would lead to episodes of seizures. “Knowing when a seizure might happen could dramatically improve the quality of life and independence of people with epilepsy and potentially allow them to avoid dangerous situations, such as driving or swimming, or to take drugs to stop the seizures before they start,” Dr. Mark Cook said. “The first thing of this was to give people back some independence. If they know when a seizure is going to happen, they can arrange their lives to be better, make themselves safer, go about work and so on in a much more comfortable and relaxed way.” His complete findings were published Thursday night in the prestigious journal, Lancet Neurology. Epilepsy is a physical condition marked by sudden, brief changes in the brain’s functioning. The unusual activity in the brain causes patients to have recurring, unprovoked seizures. There is a wide spectrum when identifying a seizure, from convulsions on one end to tuning out for just a few seconds before returning to regular activities. Device monitors abnormal brain activity in patients In the study, 15 people with focal epilepsy between the ages of 20 and 62 had the device implanted between the skull and brain surface. The study participants typically experienced between two and 12 seizures per month. Although most cases of epilepsy can be treated with medication, theirs was not responsive to at least two drug therapies. The device, developed by Seattle-based company NeuroVista, monitors electrical activity in the brain. Once abnormal electrical activity is flagged, the device sends a message to a second device implanted under the skin of the chest similar to a pacemaker. The information then makes its way to a wireless, hand-held device that calculates the likelihood of a seizure. Three coloured lights – red, white or blue – warn users of the probability of encountering a seizure. The researchers found that the system was right about “high warning” of seizures more than 65 per cent of the time and in about 11 of the 15 subjects. Eight of the patients kept the device activated for about four months – the accuracy ranged from 56 to 100 per cent. However, three patients had serious side effects, with two needing the device to be removed. Cook said the findings are promising. If they’re replicated in larger, longer studies, the technology could even offer insight into how to prevent seizures using fast-acting drugs or brain stimulation to stifle a seizure.

neurosciencestuff:

Implanted device predicts oncoming seizures in those with epilepsy

A new device may offer hope to people with epilepsy as the technology could predict the onset of seizures in adults who have the condition and can’t be treated with medication, according to Australian scientists.

The small device is implanted in the brain. Researchers at the University of Melbourne said their proof-of-concept study found that it can successfully detect brain activity that would lead to episodes of seizures.

“Knowing when a seizure might happen could dramatically improve the quality of life and independence of people with epilepsy and potentially allow them to avoid dangerous situations, such as driving or swimming, or to take drugs to stop the seizures before they start,” Dr. Mark Cook said.

“The first thing of this was to give people back some independence. If they know when a seizure is going to happen, they can arrange their lives to be better, make themselves safer, go about work and so on in a much more comfortable and relaxed way.”

His complete findings were published Thursday night in the prestigious journal, Lancet Neurology.

Epilepsy is a physical condition marked by sudden, brief changes in the brain’s functioning.

The unusual activity in the brain causes patients to have recurring, unprovoked seizures.

There is a wide spectrum when identifying a seizure, from convulsions on one end to tuning out for just a few seconds before returning to regular activities.

Device monitors abnormal brain activity in patients

In the study, 15 people with focal epilepsy between the ages of 20 and 62 had the device implanted between the skull and brain surface.

The study participants typically experienced between two and 12 seizures per month. Although most cases of epilepsy can be treated with medication, theirs was not responsive to at least two drug therapies.

The device, developed by Seattle-based company NeuroVista, monitors electrical activity in the brain.

Once abnormal electrical activity is flagged, the device sends a message to a second device implanted under the skin of the chest similar to a pacemaker.

The information then makes its way to a wireless, hand-held device that calculates the likelihood of a seizure.

Three coloured lights – red, white or blue – warn users of the probability of encountering a seizure.

The researchers found that the system was right about “high warning” of seizures more than 65 per cent of the time and in about 11 of the 15 subjects.

Eight of the patients kept the device activated for about four months – the accuracy ranged from 56 to 100 per cent.

However, three patients had serious side effects, with two needing the device to be removed.

Cook said the findings are promising. If they’re replicated in larger, longer studies, the technology could even offer insight into how to prevent seizures using fast-acting drugs or brain stimulation to stifle a seizure.

#surgical implant      #brain      #brain disorders      #psychology      #psychiatry     
March 15th
7:39 PM
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ikenbot: How Abuse Changes a Child’s Brain Image: D. Sharon Pruitt/Flickr The brains of children raised in violent families resemble the brains of soldiers exposed to combat, psychologists say. They’re primed to perceive threat and anticipate pain, adaptations that may be helpful in abusive environments but produce long-term problems with stress and anxiety. “For them to detect early cues that might signal danger is adaptive. It allows them to react, to try and avoid the danger,” said psychologist Eamon McCrory of University College London. However, “a very similar neural signature characterizes quite a few anxiety disorders.” In a study published Dec. 5 in Current Biology, McCrory’s team used functional magnetic resonance imaging, or fMRI, to measure blood flows in the brains of 43 children exposed to violence at home as they looked at pictures of sad or angry faces. Previous studies have shown that abuse affects kids’ brains; as they grow up, abused children become adults with high levels of aggression, anxiety, depression and other behavioral problems. But according to McCrory, the new study is the first to use fMRI to study the form of those changes. “Understanding the neural mechanisms might give us clues as to how someone’s future might be shaped by their experience,” McCrory said. His team compared fMRIs from abused children to those of 23 non-abused but demographically similar children from a control group. In the abused children, angry faces provoked distinct activation patterns in their anterior insula and right amygdala, parts of the brain involved in processing threat and pain. Similar patterns have been measured in soldiers who’ve seen combat. Another recent study found that depression in people who were abused as children is especially difficult to treat. McCrory hopes future work will give a more complete picture of abuse’s neurological effects — and, perhaps, the effects of interventions that help children heal. “Can children change in response to an act of intervention? To a better home environment? We’re quite optimistic that’s the case, that this is reversible. But that’s something we need to test,” McCrory said.

ikenbot:

How Abuse Changes a Child’s Brain

Image: D. Sharon Pruitt/Flickr

The brains of children raised in violent families resemble the brains of soldiers exposed to combat, psychologists say.

They’re primed to perceive threat and anticipate pain, adaptations that may be helpful in abusive environments but produce long-term problems with stress and anxiety.

“For them to detect early cues that might signal danger is adaptive. It allows them to react, to try and avoid the danger,” said psychologist Eamon McCrory of University College London. However, “a very similar neural signature characterizes quite a few anxiety disorders.”

In a study published Dec. 5 in Current Biology, McCrory’s team used functional magnetic resonance imaging, or fMRI, to measure blood flows in the brains of 43 children exposed to violence at home as they looked at pictures of sad or angry faces.

Previous studies have shown that abuse affects kids’ brains; as they grow up, abused children become adults with high levels of aggression, anxiety, depression and other behavioral problems. But according to McCrory, the new study is the first to use fMRI to study the form of those changes.

“Understanding the neural mechanisms might give us clues as to how someone’s future might be shaped by their experience,” McCrory said.

His team compared fMRIs from abused children to those of 23 non-abused but demographically similar children from a control group. In the abused children, angry faces provoked distinct activation patterns in their anterior insula and right amygdala, parts of the brain involved in processing threat and pain. Similar patterns have been measured in soldiers who’ve seen combat.

Another recent study found that depression in people who were abused as children is especially difficult to treat. McCrory hopes future work will give a more complete picture of abuse’s neurological effects — and, perhaps, the effects of interventions that help children heal.

“Can children change in response to an act of intervention? To a better home environment? We’re quite optimistic that’s the case, that this is reversible. But that’s something we need to test,” McCrory said.

#news      #brain      #violence      #science      #psychology      #child      #children      #abuse     
7:13 PM
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neuromorphogenesis:

Myths about right vs. left sides of the brain continue and can get in our way

Published on January 7, 2013 by Robert Klitzman, M.D. in Am I My Genes?

When I trained as a psychiatrist, one of my wisest professors kept in his office on an old wooden filing cabinet a 19th century ceramic phrenology head. Thick black lines divided the shiny white life-sized ceramic skull into over 20 sections, each labeled with a psychological trait – intelligence, creativity, individuality, secretiveness, combativeness, benevolence, veneration, wonder and hope.

Phrenology, which flourished in the 1820s and 1830s, claimed that bumps on one’s head corresponded to these various traits, and could be measured by assessing the size of each bump. [See attached phrenology picture.] By the middle of the 19th Century, scientists had debunked the theory.

My professor displayed this sculpture to remind us of our hubris in trying to understand the vast complexities of the human mind – how much we once thought we understood about the brain, and how little we actually grasped

Yet debates about whether different parts of the brain are primarily responsible for various mental traits – and if so, which traits and which parts — have continued.

 A few mental functions have been localized – most famously Wernicke’s and Broca’s areas involved in understanding and using language. But recent functional magnetic imaging (fMRI) research suggests that for most other complex mental tasks, the brain is far more integrative – working as a whole, involving numerous parts and networks.

Still, myths have continued – including those concerning differences between the right and left side of the brain.

Over ten million people have watched Jill Bolte Taylor’s TED talk, My Stroke of Insight, and more view it each day. Yet it raises several of these issues anew. 

Her story is powerful and moving. She suffered a terrible stroke, and eventually recovered. Yet she concludes that the right side of the brain puts us in touch with ”the life force power of the universe”, and that to find peace and Nirvana, we should choose to move away from our left hemisphere, with its focus on the single individual, and listen to the “deep inner peace” of the right hemisphere.

As I describe in my book, When Doctors Become Patients, professionals in health care and research, when becoming patients themselves, often have important lessons to teach the rest of us, as they can see their experiences with unique “double lenses” — as both patients, and scientists or clinicians. Her vivid description of the deficits caused by her stroke should make us all understand more fully the challenges that millions of Americans face following strokes or other neurological symptoms.

I agree with her that we need to engage with each other more fully, and seek happiness and peace. I do not question her experiences of what she endured.

But her explanations of the differences between the right and left sides of the brain are inaccurate, and promote several myths.

In the 1960s, Michael Gazzaniga and Roger Sperry studied patients in whom surgeons had cut certain connections between the two parts of the brain to try to reduce epileptic seizures. This research suggested that in these patients, each hemisphere might then come to specialize in different tasks.

Soon, the right brain became romanticized as the seat of creativity and freedom, as opposed to the “logical”, “analytical” and constraining left side. Individuals and whole societies have been described as being more or less right or left brained. New Age, self-help gurus have claimed to help people develop the right sides of their brains.

Yet recent fMRI research, illustrating the far vaster networking complexities of the brain as a whole, remind us how little we know.

For normal brains, in which surgeons have not cut those crucial connections, the two sides work closely together.

Still, the notion that parts of the brain are responsible for certain traits continues to have a certain allure. In part, we have entered an age of neuromythology, and neuroessentialism – in which we look for “brain explanations” of complex mental phenomena. In the past, many people invoked various theories from astrology to Freud to explain, and often try to solve psychological problems.

Now, notions of right brain and left brain seemingly make sense of certain human conflicts and difficulties, providing ready explanations for traits that we like or don’t like in ourselves or others. Our brains or large parts of our brains – not we ourselves – are somehow responsible.

Yet simplifying the brain in this way into simple binaries – with one half implicitly better than the other — ignores critical intricacies, challenges and unknowns, and does ourselves, and our brains a disservice. 

Perhaps Nature’s most complex and sophisticated creation, the human brain is filled with mysteries that should inspire us all, and can lead to better understandings and treatments for a wide range of mental problems.

I wish we could all reach Nirvana simply by turning off one side of our brain; but the reality is far more complex. We cannot shut off half our brain – nor should we try to. Rather, it is important to understand the inherent tensions, uncertainties and puzzles of human existence, and of relationships between ourselves and others. Humans evolved with competing desires – not just togetherness and love, but jealousy, ambition, and protection of kin over strangers, etc. 

We should pursue the ends she advocates of greater peace and togetherness, but be careful not to oversimplify the brain and ignore science. We will best meet her worthy goals if we recognize, accept and learn how to confront the competing daily pressures that make these ideals difficult. 

As we enter the 21st century, the history of 19th century phrenology has much to teach us about how much we think we know about the brain, and how careful we need to be.

#psychology      #brain      #science      #medicine     
March 2nd
3:53 PM
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neuromorphogenesis:

Trick yourself into an out-of-body experience

Your mind isn’t as firmly anchored in your body as you think. Time for some sleight of hand

CLOSE your eyes and ask yourself: where am I? Not geographically, but existentially. Most of the time, we would say that we are inside our bodies. After all, we peer out at the world from a unique, first-person perspective within our heads – and we take it for granted.

We wouldn’t be so sanguine if we knew that this feeling of inhabiting a body is something the brain is constantly constructing. But the fact that we live inside our bodies doesn’t mean that our sense of self is confined to its borders – as these next examples show.

Sleight of (rubber) hand

By staging experiments that manipulate the senses, we can explore how the brain draws – and redraws – the contours of where our selves reside.

One of the simplest ways to see this in action is via an experiment that’s now part of neuroscience folklore: the rubber hand illusion. The set up is simple: a person’s hand is hidden from their view by a screen while a rubber hand is placed on the table in front of them. By stroking their hand while they see the rubber hand being stroked, you can make them feel that the fake hand is theirs (see diagram).

Why does this happen? The brain integrates various senses to create aspects of our bodily self. In the rubber hand illusion, the brain is processing touch, vision and proprioception – the internal sense of the relative location of our body parts. Given the conflicting information, the brain resolves it by taking ownership of the rubber hand.

The implication is that the boundaries of the self sketched out by the brain can easily expand to include a foreign object. And the self’s peculiar meanderings outside the body don’t end there.

Trading places

Ever wish you had someone else’s body? The brain can make it happen. To show how, Henrik Ehrsson at the Karolinska Institute in Stockholm, Sweden, and colleagues transported people out of their own bodies and into a life-size mannequin.

The mannequin had cameras for eyes, and whatever it was “seeing” was fed into a head-mounted display worn by a volunteer. In this case, the mannequin’s gaze was pointed down at its abdomen. When the researchers stroked the abdomens of both the volunteer and the mannequin at the same time, many identified with the mannequin’s body as if it was their own.

In 2011, the team repeated the experiment, but this time while monitoring the brain activity of volunteers lying in an fMRI scanner. They found that activity in certain areas of the frontal and parietal lobes correlated with the changing sense of body ownership.

So what’s happening? Studies of macaque monkeys show us that these brain regions contain neurons that integrate vision, touch and proprioception. Ehrsson thinks that in the human brain such neurons fire only when there are synchronous touches and visual sensations in the immediate space around the body, suggesting that they play a role in constructing our sense of body ownership. Mess with the information the brain receives, and you can mess with this feeling of body ownership.

Yet while Ehrsson’s study manipulated body ownership, the person “inside” the mannequin still had a first-person perspective – their self was still located within a body, even if it wasn’t their own. Could it be possible to wander somewhere where there is no body at all?

Into thin air

Your self even can be tricked into hovering in mid-air outside the body. In 2011, Olaf Blanke at the Swiss Federal Institute of Technology (EPFL) in Lausanne and colleagues asked volunteers to lie on their backs and via a headset watch a video of a person of similar appearance being stroked on the back. Meanwhile, a robotic arm installed within the bed stroked the volunteer’s back in the same way.

The experience that people described was significantly more immersive than simply watching a movie of someone else’s body. Volunteers felt they were floating above their own body, and a few experienced a particularly strange effect. Despite the fact that they were all lying facing upwards, some felt they were floating face down so they could watch their own back (see “Leaving the body”). “I was looking at my own body from above,” said one participant. “The perception of being apart from my own body was a bit weak but still there.”

“That was for us really exciting, because it gets really close to the classical out-of-body experience of looking down at your own body,” says team member Bigna Lenggenhager, now at the University of Bern in Switzerland. Further support came by repeating the experiment inside an MRI scanner, which showed a brain region called the temporoparietal junction (TPJ) behaving differently when people said they were drifting outside their bodies. This ties in neatly with previous studies of brain lesions in people who reported out-of-body experiences, which also implicated the TPJ.

The TPJ shares a common trait with other brain regions that researchers believe are associated with body illusions: it helps to integrate visual, tactile and proprioceptive senses with the signals from the inner ear that give us our sense of balance and spatial orientation. This provides more evidence that the brain’s ability to integrate various sensory stimuli plays a key role in locating the self in the body.

According to philosopher Thomas Metzinger of the Johannes Gutenberg University in Mainz, Germany, understanding how the brain performs this trick is the first step to understanding how the brain puts together our autobiographical self – the sense we have of ourselves as entities that exist from a remembered past to an imagined future. “These experiments are very telling, because they manipulate low-level dimensions of the self: self-location and self-identification,” he says. The feeling of owning and being in a body is perhaps the most basic facet of self-consciousness, and so could be the foundation on which more complex aspects of the self are built. The body, it seems, begets the self.

#nueroscience      #brain      #psychology      #mind      #science     
November 13th
1:44 PM
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neurosciencestuff: Research suggests that humans are slowly but surely losing intellectual and emotional abilities Human intelligence and behavior require optimal functioning of a large number of genes, which requires enormous evolutionary pressures to maintain. A provocative hypothesis published in a recent set of Science and Society pieces published in the Cell Press journal Trends in Genetics (1, 2) suggests that we are losing our intellectual and emotional capabilities because the intricate web of genes endowing us with our brain power is particularly susceptible to mutations and that these mutations are not being selected against in our modern society. “The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples before our ancestors emerged from Africa,” says the papers’ author, Dr. Gerald Crabtree, of Stanford University. In this environment, intelligence was critical for survival, and there was likely to be immense selective pressure acting on the genes required for intellectual development, leading to a peak in human intelligence.

neurosciencestuff:

Research suggests that humans are slowly but surely losing intellectual and emotional abilities

Human intelligence and behavior require optimal functioning of a large number of genes, which requires enormous evolutionary pressures to maintain. A provocative hypothesis published in a recent set of Science and Society pieces published in the Cell Press journal Trends in Genetics (1, 2) suggests that we are losing our intellectual and emotional capabilities because the intricate web of genes endowing us with our brain power is particularly susceptible to mutations and that these mutations are not being selected against in our modern society.

“The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples before our ancestors emerged from Africa,” says the papers’ author, Dr. Gerald Crabtree, of Stanford University. In this environment, intelligence was critical for survival, and there was likely to be immense selective pressure acting on the genes required for intellectual development, leading to a peak in human intelligence.

#brain      #intelligence      #genetics      #neuroscience      #psychology     
October 15th
6:35 AM
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Study shows old adage ‘sleep on it’ is true – but only if it’s a really difficult problem A new study from Lancaster University has found that sleeping on a problem really can help people to find a solution. The study, published online this week in the journal Memory & Cognition, tested whether sleep or time spent awake worked best in helping people find the solutions to a range of problem solving tasks. The authors of the study - Ut Na Sio, Padraic Monaghan and Tom Ormerod all from the Centre for Research in Human Development and Learning at Lancaster’s Department of Psychology - concluded that sleep facilitates problem solving but this has its primary effect for harder problems. Professor Padraic Monaghan said: “We’ve known for years that sleep has a profound effect on our ability to be creative and find new solutions to problems. Our study shows that this sleep effect is greatest when the problems facing us are difficult. Sleep appears to help us solve problems by accessing information that is remote to the initial problem, that may not be initially brought to mind. Sleep has been proposed to ‘spread activation’ to the solution that is initially distant from our first attempts at the problem. The advice stemming from this and related research is to leave a problem aside if you’re stuck, and get some sleep if it’s a really difficult problem.”

Study shows old adage ‘sleep on it’ is true – but only if it’s a really difficult problem

A new study from Lancaster University has found that sleeping on a problem really can help people to find a solution.

The study, published online this week in the journal Memory & Cognition, tested whether sleep or time spent awake worked best in helping people find the solutions to a range of problem solving tasks.

The authors of the study - Ut Na Sio, Padraic Monaghan and Tom Ormerod all from the Centre for Research in Human Development and Learning at Lancaster’s Department of Psychology - concluded that sleep facilitates problem solving but this has its primary effect for harder problems.

Professor Padraic Monaghan said: “We’ve known for years that sleep has a profound effect on our ability to be creative and find new solutions to problems. Our study shows that this sleep effect is greatest when the problems facing us are difficult. Sleep appears to help us solve problems by accessing information that is remote to the initial problem, that may not be initially brought to mind. Sleep has been proposed to ‘spread activation’ to the solution that is initially distant from our first attempts at the problem. The advice stemming from this and related research is to leave a problem aside if you’re stuck, and get some sleep if it’s a really difficult problem.”

#brain      #sleep      #psychology      #cognitive      #cognition      #news      #article      #interesting     
October 9th
10:29 AM
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neurosciencestuff: A new field of developmental neuroscience changes our understanding of the early years of human life Biological Embedding of Early Social Adversity: From Fruit Flies to Kindergartners, a special volume published in the Proceedings of the National Academy of Sciences (1, 2, 3) and authored largely by researchers of the Canadian Institute for Advanced Research (CIFAR), sets out an emerging new field of the developmental science of childhood adversity. The implications of the research are far reaching, from new approaches to learning and language acquisition, to new considerations for the health effects of social environments affecting large populations, and policies for early childhood care and education. “CIFAR’s multidisciplinary and international program in early childhood development is transforming our understanding of how early life experiences affect the development of the brain and in so doing set a lifelong trajectory,” says Dr. Alan Bernstein, CIFAR President & CEO. “This research is providing the scientific basis for public policy concerning the critical window to provide the optimal conditions that will enable our children to grow up to be well-adjusted, well-educated and productive individuals.”

neurosciencestuff:

A new field of developmental neuroscience changes our understanding of the early years of human life

Biological Embedding of Early Social Adversity: From Fruit Flies to Kindergartners, a special volume published in the Proceedings of the National Academy of Sciences (1, 2, 3) and authored largely by researchers of the Canadian Institute for Advanced Research (CIFAR), sets out an emerging new field of the developmental science of childhood adversity.

The implications of the research are far reaching, from new approaches to learning and language acquisition, to new considerations for the health effects of social environments affecting large populations, and policies for early childhood care and education.

“CIFAR’s multidisciplinary and international program in early childhood development is transforming our understanding of how early life experiences affect the development of the brain and in so doing set a lifelong trajectory,” says Dr. Alan Bernstein, CIFAR President & CEO. “This research is providing the scientific basis for public policy concerning the critical window to provide the optimal conditions that will enable our children to grow up to be well-adjusted, well-educated and productive individuals.”

#neurology      #psychiatry      #psychology      #brain      #children      #development      #kids      #babies     
September 21st
6:21 PM
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Brain study reveals the roots of chocolate temptations Researchers have new evidence in rats to explain how it is that chocolate candies can be so completely irresistible. The urge to overeat such deliciously sweet and fatty treats traces to an unexpected part of the brain and its production of a natural, opium-like chemical, according to a report published online on September 20th in Current Biology, a Cell Press publication. “This means that the brain has more extensive systems to make individuals want to overconsume rewards than previously thought,” said Alexandra DiFeliceantonio of the University of Michigan, Ann Arbor. “It may be one reason why overconsumption is a problem today.” DiFeliceantonio’s team made the discovery by giving rats an artificial boost with a drug delivered straight to a brain region called the neostriatum. Those animals gorged themselves on more than twice the number of M&M chocolates than they would otherwise have eaten. The researchers also found that enkephalin, the natural drug-like chemical produced in that same brain region, surged when rats began to eat the candy-coated morsels, too. It’s not that enkephalins or similar drugs make the rats like the chocolates more, the researchers say, but rather that the brain chemicals increase their desire and impulse to eat them. The findings reveal a surprising extension of the neostriatum’s role, as DiFeliceantonio notes that the brain region had primarily been linked to movement. And there is reason to expect that the findings in rats can tell us a lot about our own binge-eating tendencies. “The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes,” she says. “It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of overconsumption and addiction in people.” The researchers now hope to unravel a related phenomenon that some of us might wish we could do more to control: what happens in our brains when we pass by our favorite fast food restaurant and feel that sudden desire to stop.

Brain study reveals the roots of chocolate temptations

Researchers have new evidence in rats to explain how it is that chocolate candies can be so completely irresistible. The urge to overeat such deliciously sweet and fatty treats traces to an unexpected part of the brain and its production of a natural, opium-like chemical, according to a report published online on September 20th in Current Biology, a Cell Press publication.

“This means that the brain has more extensive systems to make individuals want to overconsume rewards than previously thought,” said Alexandra DiFeliceantonio of the University of Michigan, Ann Arbor. “It may be one reason why overconsumption is a problem today.”

DiFeliceantonio’s team made the discovery by giving rats an artificial boost with a drug delivered straight to a brain region called the neostriatum. Those animals gorged themselves on more than twice the number of M&M chocolates than they would otherwise have eaten. The researchers also found that enkephalin, the natural drug-like chemical produced in that same brain region, surged when rats began to eat the candy-coated morsels, too.

It’s not that enkephalins or similar drugs make the rats like the chocolates more, the researchers say, but rather that the brain chemicals increase their desire and impulse to eat them.

The findings reveal a surprising extension of the neostriatum’s role, as DiFeliceantonio notes that the brain region had primarily been linked to movement. And there is reason to expect that the findings in rats can tell us a lot about our own binge-eating tendencies.

“The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes,” she says. “It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of overconsumption and addiction in people.”

The researchers now hope to unravel a related phenomenon that some of us might wish we could do more to control: what happens in our brains when we pass by our favorite fast food restaurant and feel that sudden desire to stop.

#science      #brain      #neurology      #psychology      #article      #news      #research     
September 15th
5:36 AM
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Neuroscience: Rewiring the Autistic Brain

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Signs of autism—such as impaired social skills and repetitive, ritualistic movements—usually begin to appear when a child is about 18 months old. Autism is thought to result from miswired connections in the developing brain, and many experts believe that therapies must begin during a “critical…

#psychology      #brain      #neurology      #autism