Proceedings of the National Academy of Sciences of the United States of America

Man flu is no myth say scientists, with ‘manly’ men more susceptible

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Men with high levels of testosterone have a secret flaw – less effective immune systems, researchers have discovered

Man flu may not be a myth after all, as scientist have found that men with high levels of testosterone have a hidden flaw – weak immune systems.

The discovery could explain why men are more susceptible than women to a whole range of bacterial, viral, fungal and parasitic infections, researchers said.

It may also be the reason why men’s immune systems respond less strongly to vaccinations against influenza, yellow fever, measles and hepatitis, along with many other infectious diseases.

Those who take testosterone supplements in the quest to gain muscle meanwhile, could be making themselves more susceptible to illness.

“This is the first study to show an explicit correlation between testosterone levels, gene expression and immune responsiveness in humans,” said US lead scientist Professor Mark Davis, from Stanford University.

“It could be food for thought to all the testosterone-supplement takers out there.”

The researchers studied how the immune systems of 34 men and 53 women were stimulated by the flu vaccine.

The jab generated a bigger boost in protective antibodies in women, with further analysis revealing activity that, in high testosterone men, was associated with a weakened antibody response. Men with low testosterone were not affected the same way.

Testosterone’s anti-inflammatory properties may explain why it can weaken the immune system, said scientists writing in the journal Proceedings of the National Academy of Sciences.

Prof Davies said the reason why testosterone weakens the immune system yet boosts muscle power and aggression, may be linked to the man’s evolutionary role.

Men are more likely than women to suffer injuries from competitive encounters, as well as their traditional roles of hunting, defence and potentially dangerous physical work, Prof Davies said. The dampening down the immune system makes male less susceptible to a potentially fatal over-reaction to infections, especially those from wounds.

“Ask yourself which sex is more likely to clash violently with, and do grievous bodily harm to, others of their own sex,” Prof Davis added.

New sensor tracks zinc in cells, could be exploited for early diagnosis of prostate cancer

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Zinc, an essential nutrient, is found in every tissue in the body. The vast majority of the metal ion is tightly bound to proteins, helping them to perform biological reactions. Tiny amounts of zinc, however, are only loosely bound, or “mobile,” and thought to be critical for proper function in organs such as the brain, pancreas, and prostate gland. Yet the exact roles the ion plays in biological systems are unknown.

 

 

 

A new optical sensor created at MIT tracks  within cells and should help researchers learn more about its functions. The sensor, which can be targeted to a specific organelle within the cell, fluoresces when it binds to zinc, allowing scientists to determine where the metal is concentrated.

The MIT chemists who designed the sensor have already used it to shed light on why zinc levels, normally high in the prostate, drop dramatically in cancerous prostate cells.

“We can use these tools to study zinc trafficking within prostate cells, both healthy and diseased. By doing so we’re trying to gain insight into how zinc levels within the cell change during the progression of prostate cancer,” says Robert Radford, an MIT postdoc who led the project and who is an author of the paper describing the sensors, which appears in the Dec. 9 issue of theProceedings of the National Academy of Sciences.

Radford works in the lab of Stephen Lippard, the Arthur Amos Noyes Professor of Chemistry and senior author of the paper. The paper’s lead author is Wen Chyan, a 2013 MIT graduate.

Researchers in Lippard’s lab are now working on exploiting similar fluorescent sensors to develop a diagnostic test for early detection of , which is the second leading cause of cancer death in American men, but is considered very treatable if caught early enough.

Pathway to cancer

Among its known roles, zinc helps to stabilize protein structure and catalyzes some cellular reactions. In the prostate, zinc is believed to help with reproductive functions by aiding in the accumulation of citrate, a component of semen. Within mitochondria of epithelial prostate cells, zinc has been shown to inhibit the metabolic enzyme aconitase. By blocking the activity of aconitase, zinc truncates the citric acid cycle, the series of reactions that produce ATP, the cells’ major energy currency.

Scientists have theorized that when prostate cells become cancerous, they banish zinc from mitochondria (the cell structures where most ATP production occurs). This allows the cancer cell to produce the extra energy it needs to grow and divide.

“If a cell is dividing uncontrollably and it needs a lot of chemical energy, then it definitely wouldn’t want zinc interfering with aconitase and preventing production of more ATP,” Radford says.

The new MIT study supports this theory by showing that, although cancerous prostate cells can absorb zinc, the metal does not accumulate in the mitochondria, as it does in normal .

This finding suggests that, in normal cells, zinc is probably transported into mitochondria by a specialized transport protein, but such a protein has not been identified, Radford says. In cancer cells, this protein might be inactivated.

Follow the zinc

The new zinc sensor relies on a molecule that Lippard’s lab first developed more than 10 years ago, known as Zinpyr1 (ZP1). ZP1 is based on a dye known as fluorescein, but it is modified to fluoresce only when it binds to zinc.

The ZP1 sensor can simply be added to a dish of cells grown in the lab, where it will diffuse into the cells. Until now, a major drawback of the sensor was the difficulty in targeting specific structures within a cell. “We have had some success using proteins and peptides to target small molecule zinc sensors,” Radford says, “but most of the time the sensors get captured in acidic vesicles within the cell and become inactive.”

Lippard’s team overcame that obstacle by making two changes: First, they installed a zinc-reactive protecting group, which altered the physical properties of the sensor and made it easier to target. Second, they attached an “address tag” that directs ZP1 into mitochondria. This tag, which is a derivative of triphenylphosphonium, is tailored to enter the mitochondria because it is both positively charged and hydrophobic. The resulting sensor readily entered cells and allowed the researchers to visualize pools of mobile zinc within .

“This is an exciting new concept for sensing using a combination of reaction- and recognition-based approaches, which has potential applications for diagnostics involving zinc misregulation,” says Christopher Chang, a professor of chemistry and molecular and cell biology at the University of California at Berkeley who was not part of the research team.

In future studies, the researchers plan to expand their strategy to create a palette of sensors that target many other organelles in the cell.

“The identification of intracellular targets for mobile zinc is an important step in understanding its true function in biological signaling. The next steps will involve discovery of the specific biochemical pathways that are affected by zinc binding to receptors in the organelles, such as proteins, and elucidating the structural and attendant functional changes that occur in the process,” Lippard says.

The lab’s immediate interest is study of zinc in the brain, where it is believed to act as a neurotransmitter. By understanding mobile zinc in the auditory cortex, optic nerve, and olfactory bulb, the researchers hope to figure out its role in the senses of hearing, sight, and smell.

 

Men and women ‘wired differently’

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Men and women’s brains are connected in different ways which may explain why the sexes excel at certain tasks, say researchers.

A US team at the University of Pennsylvania scanned the brains of nearly 1,000 men, women, boys and girls and found striking differences.

brain networksThe “connectome maps” reveal the differences between the male brain (seen in blue) and the female brain (orange)

Male brains appeared to be wired front to back, with few connections bridging the two hemispheres.

In females, the pathways criss-crossed between left and right.

These differences might explain why men, in general, tend to be better at learning and performing a single task, like cycling or navigating, whereas women are more equipped for multitasking, say the researchers in the journal Proceedings of the National Academy of Sciences (PNAS).

The same volunteers were asked to perform a series of cognitive tests, and the results appeared to support this notion.

But experts have questioned whether it can be that simple, arguing it is a huge leap to extrapolate from anatomical differences to try to explain behavioural variation between the sexes. Also, brain connections are not set and can change throughout life.

In the study, women scored well on attention, word and face memory, and social cognition, while men performed better on spatial processing and sensori-motor speed.

To look at brain connectivity, the researchers used a type of scan called DTI – a water-based imaging technique that can trace and highlight the fibre pathways connecting the different regions of the brain.

Study author Dr Ruben Gur said: “It’s quite striking how complementary the brains of women and men really are.

“Detailed connectome maps of the brain will not only help us better understand the differences between how men and women think, but it will also give us more insight into the roots of neurological disorders, which are often sex related.”

Complex organ

Prof Heidi Johansen-Berg, a UK expert in neuroscience at the University of Oxford, said the brain was too complex an organ to be able to make broad generalisations.

“We know that there is no such thing as ‘hard wiring’ when it comes to brain connections. Connections can change throughout life, in response to experience and learning.

“Often, sophisticated mathematical approaches are used to analyse and describe these brain networks. These methods can be useful to identify differences between groups, but it is often challenging to interpret those differences in biological terms.”

Dr Michael Bloomfield, Clinical Research Fellow at the Medical Research Council Clinical Sciences Centre in London, said: “It has been known for some time that there are differences between the sexes when it comes to how our bodies work and the brain is no exception.

However, he said care must be taken in drawing conclusions from the study, as the precise relationships between how our brains are wired and our performance on particular tasks needed further investigation.

“We cannot say yet that one is causing the other.

“Furthermore, the measure used in the study, called “connectivity”, is only one aspect of how our brains our wired.

“We think that there can also be differences in certain chemicals in the brain called neurotransmitters, for example, and so we need more research to fully understand how all these different aspects of brain structure and function work together to answer fundamental questions like “how do we think?”.

“One thing that remains unknown is what is driving these differences between the sexes. An obvious possibility is that that male hormones like testosterone and female hormones like oestrogren have different affects on the brain.

“A more subtle possibility is that bringing a child up in a particular gender could affect how our brains are wired.”

 

Why it’s time for brain science to ditch the ‘Venus and Mars’ cliche.

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Reports trumpeting basic differences between male and female brains are biological determinism at its most trivial, says the science writer of the year
brains illustration male female

There is little evidence to suggest differences between male and female brains are caused by anything other than cultural factors. Photograph: Alamy

As hardy perennials go, there is little to beat that science hacks’ favourite: the hard-wiring of male and female brains. For more than 30 years, I have seen a stream of tales about gender differences in brain structure under headlines that assure me that from birth men are innately more rational and better at map-reading than women, who are emotional, empathetic multi-taskers, useless at telling jokes. I am from Mars, apparently, while the ladies in my life are from Venus.

And there are no signs that this flow is drying up, with last week witnessing publication of a particularly lurid example of the genre. Writing in the US journal Proceedings of the National Academy of Sciences, researchers at the University of Pennsylvania in Philadelphia revealed they had used a technique called diffusion tensor imaging to show that the neurons in men’s brains are connected to each other in a very different way from neurons in women’s brains.

This point was even illustrated by the team, led by Professor Ragini Verma, with a helpful diagram. A male brain was depicted with its main connections – coloured blue, needless to say – running from the front to the back. Connections within cranial hemispheres were strong, but connections between the two hemispheres were weak. By contrast, the female brain had thick connections running from side to side with strong links between the two hemispheres.

Men and women brains U.Penn studyA photo issued by University of Pennsylvania researchers showing intra-hemispheric connections (blue) and inter- hemispheric connections (orange) in men’s and women’s brains. Male top row, female bottom row. Photograph: National Academy Of Sciences/PA”These maps show us a stark difference in the architecture of the human brain that helps provide a potential neural basis as to why men excel at certain tasks and women at others,” said Verma.

The response of the press was predictable. Once again scientists had “proved” that from birth men have brains which are hardwired to give us better spatial skills, to leave us bereft of empathy for others, and to make us run, like mascara, at the first hint of emotion. Equally, the team had provided an explanation for the “fact” that women cannot use corkscrews or park cars but can remember names and faces better than males. It is all written in our neurons at birth.

As I have said, I have read this sort of thing before. I didn’t believe it then and I don’t believe it now. It is biological determinism at its silly, trivial worst. Yes, men and women probably do have differently wired brains, but there is little convincing evidence to suggest these variations are caused by anything other than cultural factors. Males develop improved spatial skills not because of an innate superiority but because they are expected and encouraged to be strong at sport, which requires expertise at catching and throwing. Similarly, it is anticipated that girls will be more emotional and talkative, and so their verbal skills are emphasised by teachers and parents. As the years pass, these different lifestyles produce variations in brain wiring – which is a lot more plastic than most biological determinists realise. This possibility was simply not addressed by Verma and her team.

Equally, when gender differences are uncovered by researchers they are frequently found to be trivial, a point made by Robert Plomin, a professor of behavioural genetics at London’s Institute of Psychiatry, whose studies have found that a mere 3% of the variation in young children’s verbal development is due to their gender. “If you map the distribution of scores for verbal skills of boys and of girls, you get two graphs that overlap so much you would need a very fine pencil indeed to show the difference between them. Yet people ignore this huge similarity between boys and girls and instead exaggerate wildly the tiny difference between them. It drives me wild.”

I should make it clear that Plomin made that remark three years ago when I last wrote about the issue of gender and brain wiring. It was not my first incursion, I should stress. Indeed, I have returned to the subject – which is an intriguing, important one – on a number of occasions over the years as neurological studies have been hyped in the media, often by the scientists who carried them out. It has taken a great deal of effort by other researchers to put the issue in proper perspective.

A major problem is the lack of consistent work in the field, a point stressed to me in 2005 – during an earlier outbreak of brain-gender difference stories – by Professor Steve Jones, a geneticist at University College London, and author of Y: The Descent of Men. “Researching my book, I discovered there was no consensus at all about the science [of gender and brain structure],” he told me. “There were studies that said completely contradictory things about male and female brains. That means you can pick whatever study you like and build a thesis around it. The whole field is like that. It is very subjective. That doesn’t mean there are no differences between the brains of the sexes, but we should take care not to exaggerate them.”

Needless to say that is not what has happened over the years. Indeed, this has become a topic whose coverage has been typified mainly by flaky claims, wild hyperbole and sexism. It is all very depressing. The question is: why has this happened? Why is there such divergence in explanations for the differences in mental abilities that we observe in men and women? And why do so many people want to exaggerate them so badly?

The first issue is the easier to answer. The field suffers because it is bedevilled by its extraordinary complexity. The human brain is a vast, convoluted edifice and scientists are only now beginning to develop adequate tools to explore it. The use of diffusion tensor imaging by Verma’s team was an important breakthrough, it should be noted. The trouble is, once more, those involved were rash in their interpretations of their own work.

“This study contains some important data but it has been badly overhyped and the authors must take some of the blame,” says Professor Dorothy Bishop, of Oxford University. “They talk as if there is a typical male and a typical female brain – they even provide a diagram – but they ignore the fact that there is a great deal of variation within the sexes in terms of brain structure. You simply cannot say there is a male brain and a female brain.”

Even more critical is Marco Catani, of London’s Institute of Psychiatry. “The study’s main conclusions about possible cognitive differences between males and females are not supported by the findings of the study. A link between anatomical differences and cognitive functions should be demonstrated and the authors have not done so. They simply have no idea of how these differences in anatomy translate into cognitive attitudes. So the main conclusion of the study is purely speculative.”

The study is also unclear how differences in brain architecture between the sexes arose in the first place, a point raised by Michael Bloomfield of the MRC’s Clinical Science Centre. “An obvious possibility is that male hormones like testosterone and female hormones like oestrogen have different effects on the brain. A more subtle possibility is that bringing a child up in a particular gender could affect how our brains are wired.”

In fact, Verma’s results showed that the neuronal connectivity differences between the sexes increased with the age of her subjects. Such a finding is entirely consistent with the idea that cultural factors are driving changes in the brain’s wiring. The longer we live, the more our intellectual biases are exaggerated and intensified by our culture, with cumulative effects on our neurons. In other words, the intellectual differences we observe between the sexes are not the result of different genetic birthrights but are a consequence of what we expect a boy or a girl to be.

Why so many people should be so desperate to ignore or obscure this fact is a very different issue. In the end, I suspect it depends on whether you believe our fates are sealed at birth or if you think that it is a key part of human nature to be able to display a plasticity in behaviour and in ways of thinking in the face of altered circumstance. My money is very much on the latter.

WHAT THE NEW STUDY SHOWS

In their study, Verma and her colleagues, investigated the gender differences in brain connectivity in 949 individuals – 521 females and 428 males – aged between eight and 22 years. The technique they used is known as diffusion tensor imaging (DTI), a water-based imaging technology that can trace and highlight the fibre pathways that connect the different regions of the brain, laying the foundation for a structural connectome or network of the whole brain. These studies revealed a typical pattern, claim Verma and her team: men had stronger links between neurons within their cranial hemispheres while women had stronger links between the two hemispheres, a difference that the scientists claimed was crucial in explaining difference in the behaviour of men and women.

But the technique has been criticised. “DTI provides only indirect measures of structural connectivity and is, therefore, different from the well validated microscopic techniques that show the real anatomy of axonal connections,” says Marco Catani, of London’s Institute of Psychiatry. “Images of the brain derived from diffusion tensor MRI should not be equated to real connections and results should always be interpreted with extreme caution.”This point is backed by Prof Heidi Johansen-Berg, of Oxford University, who attacked the idea that brain connections should be considered as hard-wired. “Connections can change throughout life, in response to experience and learning. As far as I can tell, the authors have not directly related these differences in brain connections to differences in behaviour. It is a huge leap to extrapolate from anatomical differences to try to explain behavioural variation between the sexes. The brain regions that have been highlighted are involved in many different functions.”

 

Love hormone ‘helps autistic brain’

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Child with autism

The “love hormone” oxytocin alters the brain activity of children with autism and makes them more social, according to US researchers.

The role of the hormone in helping children with autism has been debated, with studies showing conflicting data.

Brain scans, reported in the Proceedings of the National Academy of Sciences, hint that there is an effect.

The National Autistic Society said research on oxytocin as a treatment was still in its infancy.

What is autism?

  • Autism and Asperger’s syndrome are part of a range of disorders that can cause difficulties with communication and social skills
  • The conditions can lead to isolation and emotional problems for those living with them
  • Conditions can vary from very mild, where the person can function as well as anyone else, to so severe they cannot take part in normal society
  • The conditions are collectively known as autistic spectrum disorders and affect more than 580,000 people in the UK

Oxytocin is naturally produced by the body, triggers labour and is involved in mother and baby bonding.

Seventeen children with autism, aged between eight and 16, were given two nasal spray – one containing oxytocin, the other no drugs at all.

After taking each one, the impact on brain activity was recorded in a scanner while the children were shown “social” pictures of human faces or “non-social” pictures of cars.

The parts of the brain normally associated with social situations appeared more active after the children had been given oxytocin.

‘Exciting’

One of the researchers, Prof Kevin Pelphrey, told the BBC: “We are very excited by the findings, all 17 showed a response, although the response was variable.

“There’s still lots of questions about oxytocin, but this suggests it enhances social brain functions and decreases non-social functions – helping kids to focus on socially relevant information.”

Larger trials are taking place to see what the side-effects and benefits of oxytocin might be in children with autism.

Exactly how the drug should be used is still up for debate, with some suggestions that it would be best used as an aid during current behavioural therapy rather than as a daily medication.

Prof Pelphrey said some parents were giving the drug to their children without medical advice and this was a “terrible idea”.

“It might have no effect or it might cause damage,” he said.

However, he added: “The most exciting finding is not oxytocin, but that you can show changes in the brain by a compound.

“It changes how we think of autism and how treatable it might be.”

Carol Povey, director of the National Autistic Society’s centre for autism, said: “Research investigating the impact oxytocin can have on people with autism is still in its very early stages.

“While the findings of this particular study are interesting, no hard and fast conclusions should be drawn.

“Autism is a very complex disability and can present a variety of challenges that extend beyond social difficulties.

“It’s crucial that those living with the condition have all their needs assessed so that they can access the appropriate support.”

Male pill keeps sperm ‘in storage’

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Sperm

The prospect of a “male pill” that would let men enjoy a full sex life with no chance of getting a woman pregnant has moved a step closer.

Scientists in Australia have found a reversible way to stop sperm getting into the ejaculate, without affecting sexual function.

The animal tests showed the sperm could be “kept in storage” during sex.

The findings were published in the journal Proceedings of the National Academy of Sciences.

The quest for the male contraceptive pill has largely focused on getting men to produce non-functional sperm.

But some drugs used for this purpose “have intolerable side-effects,” said Dr Sabatino Ventura, one of the researchers at Monash University.

Drugs can induce infertility, but they may also affect sexual appetite or cause permanent alterations to sperm production.

Sperm stores

The team at Monash used a different approach. Normally, the sperm is moved out of the vas deferens storage area in the testes just before ejaculation.

The group produced genetically modified mice that were unable to squeeze the sperm out of the vas deferens.

Dr Ventura told the BBC: “The sperm stay in the storage site so when the mice ejaculate there’s no sperm and they are infertile.

“It is readily reversible and the sperm are unaffected, but we need to show we can do this pharmacologically, probably with two drugs.”

So far the research group has made the mice infertile by changing their DNA to stop them producing two proteins needed to move the sperm.

The researchers now need to find a pair of drugs that can produce the same effect. They believe one has already been developed and has been used for decades in patients with benign prostate enlargement.

However, they would have to work from scratch to find the second one – a process that could take a decade.

The proteins targeted also have a role in controlling blood vessels; so there could be side-effects on blood pressure and heart rate.

However, in the mice at least, the researchers detected only a “very slight” drop in blood pressure. There could also be an impact on the volume of ejaculate.

Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield , told the BBC: “It’s a very good study, almost like a biological vasectomy in [that] it stops the sperm coming out.

“It’s a good idea; they need to get on with it and see what it does in people.”

Men can’t multitask, women have better memory, study led by Indian-origin scientist reveals.

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Men can’t multitask and women have better memory because their brains are wired differently, a new study led by an Indian-origin scientist has found.

The research found striking differences in the neural wiring of men and women, which explains why males excel at certain tasks and females at others.

In one of the largest studies looking at the “connectomes” of the sexes, Ragini Verma, an associate professor in the department of radiology at the Perelman School of Medicine at the University of Pennsylvania, and colleagues found greater neural connectivity from front to back and within one hemisphere in males.

This suggests male brains are structured to facilitate connectivity between perception and coordinated action.

In contrast, in females, the wiring goes between the left and right hemispheres, suggesting that they facilitate communication between the analytical and intuition.

“These maps show us a stark difference – and complementarity – in the architecture of the human brain that helps provide a potential neural basis as to why men excel at certain tasks, and women at others,” said Verma, who has a PhD in computer vision and mathematics from Indian Institute of Technology Delhi.

In the study, Verma and colleagues investigated the gender-specific differences in brain connectivity during the course of development in 949 individuals (521 females and 428 males) aged 8 to 22 years using diffusion tensor imaging.

DTI is water-based imaging technique that can trace and highlight the fiber pathways connecting the different regions of the brain, laying the foundation for a structural connectome or network of the whole brain.

Researchers found that females displayed greater connectivity in the supratentorial region, which contains the cerebrum, the largest part of the brain, between the left and right hemispheres.

Males, on the other hand, displayed greater connectivity within each hemisphere.

By contrast, the opposite prevailed in the cerebellum, the part of the brain that plays a major role in motor control, where males displayed greater inter-hemispheric connectivity and females displayed greater intra-hemispheric connectivity.

These connections likely give men an efficient system for coordinated action, where the cerebellum and cortex participate in bridging between perceptual experiences in the back of the brain, and action, in the front of the brain, researchers said in the journal Proceedings of National Academy of Sciences.

The female connections likely facilitate integration of the analytic and sequential processing modes of the left hemisphere with the spatial, intuitive information processing modes of the right side.

The authors observed only a few gender differences in the connectivity in children younger than 13 years, but the differences were more pronounced in adolescents aged 14 to 17 years and young adults older than 17.

Brain Scans Show The Real Impact Love Has On A Child’s Brain.

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You comfort them over a skinned knee in the playground, and coax them to sleep with a soothing lullaby. But being a nurturing mother is not just about emotional care – it pays dividends by determining the size of your child’s brain, scientists say.

Both of these images are brain scans of a two three-year-old children, but the brain on the left is considerably larger, has fewer spots and less dark areas, compared to the one on the right.

According to neurologists this sizable difference has one primary cause – the way each child was treated by their mothers.

But the child with the shrunken brain was the victim of severe neglect and abuse.

Babies’ brains grow and develop as they interact with their environment and learn how to function within it.

When babies’ cries bring food or comfort, they are strengthening the neuronal pathways that help them learn how to get their needs met, both physically and emotionally. But babies who do not get responses to their cries, and babies whose cries are met with abuse, learn different lessons.

The neuronal pathways that are developed and strengthened under negative conditions prepare children to cope in that negative environment, and their ability to respond to nurturing and kindness may be impaired.

According to research reported by the newspaper, the brain on the right in the image above worryingly lacks some of the most fundamental areas present in the image on the left.

The consequences of these deficits are pronounced – the child on the left with the larger brain will be more intelligent and more likely to develop the social ability to empathise with others.

This type of severe, global neglect can have devastating consequences. The extreme lack of stimulation may result in fewer neuronal pathways available for learning.

The lack of opportunity to form an attachment with a nurturing caregiver during infancy may mean that some of these children will always have difficulties forming meaningful relationships with others. But studies have also found that time played a factor–children who were adopted as young infants have shown more recovery than children who were adopted as toddlers.

But in contrast, the child with the shrunken brain will be more likely to become addicted to drugs and involved in violent crimes, much more likely to be unemployed and to be dependent on state benefits.
The child is also more likely to develop mental and other serious health problems.

Some of the specific long-term effects of abuse and neglect on the developing brain can include:

  • Diminished growth in the left hemisphere, which may increase the risk for depression
  • Irritability in the limbic system, setting the stage for the emergence of panic disorder and posttraumatic stress disorder
  • Smaller growth in the hippocampus and limbic abnormalities, which can increase the risk for dissociative disorders and memory impairments
  • Impairment in the connection between the two brain hemispheres, which has been linked to symptoms of attention-deficit/hyperactivity disorder

Professor Allan Schore, of UCLA, told The Sunday Telegraph that if a baby is not treated properly in the first two years of life, it can have a fundamental impact on development.

He pointed out that the genes for several aspects of brain function, including intelligence, cannot function.
And sadly there is a chance they may never develop and come into existence.

These has concerning implications for neglected children that are taken into care past the age of two.
It also seems that the more severe the mother’s neglect, the more pronounced the damage can be.

The images also have worrying consequences for the childhood neglect cycle – often parents who, because their parents neglected them, do not have fully developed brains, neglect their own children in a similar way.

But research in the U.S. has shown the cycle can be successfully broken if early intervention is staged and families are supported.

The study correlates with research released earlier this year that found that children who are given love and affection from their mothers early in life are smarter with a better ability to learn.

The experiences of infancy and early childhood provide the organizing framework for the expression of children’s intelligence, emotions, and personalities.

When those experiences are primarily negative, children may develop emotional, behavioral, and learning problems that persist throughout their lifetime, especially in the absence of targeted interventions.

The study by child psychiatrists and neuroscientists at Washington University School of Medicine in St. Louis, found school-aged children whose mothers nurtured them early in life have brains with a larger hippocampus, a key structure important to learning, memory and response to stress.

The research was the first to show that changes in this critical region of children’s brain anatomy are linked to a mother’s nurturing, Neurosciencenews.com reports.

The research is published online in the Proceedings of the National Academy of Sciences Early Edition.
Lead author Joan L. Luby, MD, professor of child psychiatry, said the study reinforces how important nurturing parents are to a child’s development.

Sources:
childwelfare.gov

preventdisease.com

         

Researchers find tie between global precipitation and global warming.

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The rain in Spain may lie mainly on the plain, but the location and intensity of that rain is changing not only in Spain but around the globe.

A new study by Lawrence Livermore National Laboratory scientists shows that observed changes in global (ocean and land) precipitation are directly affected by human activities and cannot be explained by natural variability alone. The research appears in the Nov. 11 online edition of the Proceedings of the National Academy of Sciences.

Emissions of heat-trapping and ozone-depleting gases affect the distribution of precipitation through two mechanisms. Increasing temperatures are expected to make wet regions wetter and dry regions drier (thermodynamic changes); and changes in will push storm tracks and subtropical dry zones toward the poles.

“Both these changes are occurring simultaneously in global precipitation and this behavior cannot be explained by natural variability alone,” said LLNL’s lead author Kate Marvel. “External influences such as the increase in are responsible for the changes.”

The team compared climate model predications with the Global Precipitation Climatology Project’s global observations, which span from 1979-2012, and found that natural variability (such as El Niños and La Niñas) does not account for the changes in global precipitation patterns. While natural fluctuations in climate can lead to either intensification or poleward shifts in precipitation, it is very rare for the two effects to occur together naturally.

“In combination, manmade increases in greenhouse gases and stratospheric ozone depletion are expected to lead to both an intensification and redistribution of global precipitation,” said Céline Bonfils, the other LLNL author. “The fact that we see both of these effects simultaneously in the observations is strong evidence that humans are affecting global precipitation.”

https://i0.wp.com/cdn.physorg.com/newman/gfx/news/2013/35-researchersf.jpg

Marvel and Bonfils identified a fingerprint pattern that characterizes the simultaneous response of precipitation location and intensity to external forcing.

“Most previous work has focused on either thermodynamic or dynamic changes in isolation. By looking at both, we were able to identify a pattern of precipitation change that fits with what is expected from human-caused climate change,” Marvel said.

By focusing on the underlying mechanisms that drive changes in global precipitation and by restricting the analysis to the large scales where there is confidence in the models’ ability to reproduce the current climate, “we have shown that the changes observed in the satellite era are externally forced and likely to be from man,” Bonfils said.

Vapours from damp buildings may trigger Parkinson’s

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A vapour known as “mushroom alcohol” which is present in damp, mouldy buildings can damage the nerve cells of the brain responsible for Parkinson’s disease, scientists said.

A study has found that the compound, called 1-octen-3-ol, leads to the degeneration of two genes involved with the transport and storage of dopamine, the neurotransmitter in the brain that is lost in patients with Parkinson’s.

The researchers suggest that the volatile substances given off by mildew and other fungi growing in damp houses may be a significant risk factor in the development of the degenerative brain disease, which is thought to have environmental as well as genetic causes.

The study was carried out on the dopamine system of fruit flies, a recognised animal “model” of Parkinson’s disease, and the researchers calculated that mushroom alcohol was more toxic to these specialised nerves than benzene – a poisonous chemical known to cause genetic damage.

“These findings are of particular interest given recent epidemiological studies that have raised the concern of neuropsychological impairments and movement disorders in human populations exposed to mouldy and water-damaged buildings,” the scientists said in the study published in the journal Proceedings of the National Academy of Sciences. “Increased incidence of Parkinson’s disease is seen in rural populations, where it is usually attributed to pesticide exposure. However, the prevalence of mould and mushroom in these environments may provide another plausible risk factor for the development of Parkinson’s disease.”

Until recently, the search for environmental factors that could trigger the disease has focused largely on man-made chemicals, such as pesticides. However, natural compounds could be equally to blame, said Arati Inamdar of Rutgers University.

“There have been studies indicating that Parkinson’s disease is increasing in rural areas, where it’s usually attributed to pesticide exposure. But rural environments also have a lot of exposure to moulds and other fungi, and our work suggests that 1-octen-3-ol might also be connected to the disease, particularly for people with a genetic susceptibility to it,” she added.

Joan Bennett, co-author of the study, said she took an interest in the role of fungi in health after she became ill working in her flood-damaged house in New Orleans after Hurricane Katrina in 2005.

“I knew something about ‘sick building’ syndrome, because I am an expert in toxic fungi. I didn’t believe in it, because I didn’t think it would be possible to breathe in enough mould spores to get sick,” Professor Bennett said.

But when collecting samples while wearing protective gear, she fell ill. “While I was doing the sampling, I felt horrible – headaches, dizziness and nausea. I had a conversion experience,” she said.

Claire Bale, a spokesperson for Parkinson’s UK, said that the cause of Parkinson’s disease is one of the big unanswered questions.

“We already know that exposure to some chemicals can slightly increase the risk of Parkinson’s, and this is the first study to suggest that chemicals produced by fungi may play a part,” Ms Bale said.

“It is important to remember, this study was conducted using tiny fruit flies, so before we can really be confident about this new connection we need to see evidence from studies in people,” she added.