Autism: Research focused on Men, Women are different

Autism affects different parts of the brain in females with autism than males with autism, a new study reveals. The research is published today in the journal Brain as an open-access article.

Scientists at the Autism Research Centre at the University of Cambridge used magnetic resonance imaging to examine whether autism affects the brain of males and females in a similar or different way.

They found that the anatomy of the brain of someone with autism substantially depends on whether an individual is male or female, with brain areas that were atypical in adult females with autism being similar to areas that differ between typically developing males and females. This was not seen in men with autism.

"One of our new findings is that females with autism show neuroanatomical 'masculinization'," said Professor Simon Baron-Cohen, senior author of the paper.

"This may implicate physiological mechanisms that drive sexual dimorphism, such as prenatal sex hormones and sex-linked genetic mechanisms."

Simon Baron-Cohen

Autism affects 1% of the general population and is more prevalent in males. Most studies have therefore focused on male-dominant samples.

As a result, our understanding of the neurobiology of autism is male-biased.

"This is one of the largest brain imaging studies of sex/gender differences yet conducted in autism. Females with autism have long been under-recognized and probably misunderstood," said Dr Meng-Chuan Lai, who led the research project.

"The findings suggest that we should not blindly assume that everything found in males with autism applies to females. This is an important example of the diversity within the 'spectrum'."

Dr Michael Lombardo

Dr Michael Lombardo, who co-led the study, added that although autism manifests itself in many different ways, grouping by gender may help provide a better understanding of this condition.

He said: "Autism as a whole is complex and vastly diverse, or heterogeneous, and this new study indicates that there are ways to subgroup the autism spectrum, such as whether an individual is male or female."

"Reducing heterogeneity via subgrouping will allow research to make significant progress towards understanding the mechanisms that cause autism."

Autism Risk: Exposure to high pollution levels during pregnancy

Women in the U.S. exposed to high levels of air pollution while pregnant were up to twice as likely to have a child with autism as women who lived in areas with low pollution, according to a new study from Harvard School of Public Health (HSPH).

It is the first large national study to examine links between autism and air pollution across the U.S.

Andrea Roberts

"Our findings raise concerns since, depending on the pollutant, 20% to 60% of the women in our study lived in areas where risk of autism was elevated," said lead author Andrea Roberts, research associate in the HSPH Department of Social and Behavioral Sciences.

The study appeared online June 18, 2013 in Environmental Health Perspectives.

Exposure to diesel particulates, lead, manganese, mercury, methylene chloride and other pollutants are known to affect brain function and to affect the developing baby.

Two previous studies found associations between exposure to air pollution during pregnancy and autism in children, but those studies looked at data in just three locations in the U.S.

The researchers examined data from Nurses' Health Study II, a long-term study based at Brigham and Women's Hospital involving 116,430 nurses that began in 1989.

Among that group, the authors studied 325 women who had a child with autism and 22,000 women who had a child without the disorder.

They looked at associations between autism and levels of pollutants at the time and place of birth. They used air pollution data from the U.S. Environmental Protection Agency to estimate women's exposure to pollutants while pregnant.

They also adjusted for the influence of factors such as income, education, and smoking during pregnancy.

The results showed that women who lived in the 20% of locations with the highest levels of diesel particulates or mercury in the air were twice as likely to have a child with autism as those who lived in the 20% of areas with the lowest levels.

Other types of air pollution—lead, manganese, methylene chloride, and combined metal exposure—were associated with higher autism risk as well.

Women who lived in the 20% of locations with the highest levels of these pollutants were about 50% more likely to have a child with autism than those who lived in the 20% of areas with the lowest concentrations.

Most pollutants were associated with autism more strongly in boys than girls. However, since there were few girls with autism in the study, the authors said this finding should be examined further.

Marc Weisskopf

Senior author Marc Weisskopf, associate professor of environmental and occupational epidemiology at HSPH, said, "Our results suggest that new studies should begin the process of measuring metals and other pollutants in the blood of pregnant women or newborn children to provide stronger evidence that specific pollutants increase risk of autism. A better understanding of this can help to develop interventions to reduce pregnant women's exposure to these pollutants."

Chronic Stress in Pregnancy prevents brain benefits of motherhood

A new study in animals shows that chronic stress during pregnancy prevents brain benefits of motherhood, a finding that researchers suggest could increase understanding of postpartum depression.

Rat mothers showed an increase in brain cell connections in regions associated with learning, memory and mood.

In contrast, the brains of mother rats that were stressed twice a day throughout pregnancy did not show this increase.

The researchers were specifically interested in dendritic spines – hair-like growths on brain cells that are used to exchange information with other neurons.

Previous animal studies conducted by lead author Benedetta Leuner of Ohio State University showed that an increase of dendritic spines in new mothers’ brains was associated with improved cognitive function on a task that requires behavioral flexibility – in essence, enabling more effective multitasking.

The dendritic spines increased by about 20 percent in these brain regions in new mothers, according to her findings.

The stress in this new study negated those brain benefits of motherhood, causing the stressed rats’ brains to match brain characteristics of animals that had no reproductive or maternal experience.

The stressed rats also had less physical interaction with their babies than did unstressed rats, a behaviour observed in human mothers who experience postpartum depression.

“Animal mothers in our research that are unstressed show an increase in the number of connections between neurons. Stressed mothers don’t,” said Leuner, assistant professor of psychology and neuroscience at Ohio State.

“We think that makes the stressed mothers more vulnerable. They don’t have the capacity for brain plasticity that the unstressed mothers do, and somehow that’s contributing to their susceptibility to depression.”


Previous research has suggested that there are a number of risk factors for postpartum depression, including hormone fluctuations, prior history of mental illness and environmental factors such as smoking or low socioeconomic status.

One of the strongest predictors, however, is chronic stress during pregnancy, so Leuner sought to create an animal model that could help explain brain changes linked to postpartum depression.

“It’s devastating not only for the mother, because it affects her well-being, but previous research also has shown that children of depressed mothers have impaired cognitive and social development, may have impaired physical development, and are more likely as adults to have depression or anxiety,” she said.

“A better understanding of postpartum depression is important to help the mother but also to prevent some of the damaging effects that this disorder can have on the child.”

The researchers exposed pregnant rats to stress twice a day by limiting their mobility on some days and on other days placing them in water. For three weeks after the rats gave birth, Leuner and colleagues monitored the rats.

The animals showed classic signs of the effects of stress, including lower than normal weight gain and enlarged adrenal glands, a sign of high stress-hormone production. The mothers stressed during pregnancy also gave birth to smaller pups.

“And they were not very good mothers,” Leuner said. After separation from pups for 30 minutes, unstressed mothers would gather up their babies, put them in the nest and nurse them. Stressed mother rats left the pups scattered around, wandered around the cage and fed the babies less frequently.

The stressed mother rats also exhibited more floating than unstressed rats in a water test; animals that float rather than swim are showing depressive-like symptoms.

“These findings in rats mimic some of the symptoms that are seen in women with postpartum depression,” Leuner said.

An examination of the animals’ brains showed that the rats exposed to chronic stress did not grow the additional dendritic spines in the hippocampus and prefrontal cortex that the unstressed mother rats did.

The stressed rats’ brains more closely resembled the brains of control rats that had never been mothers.

“We don’t yet know what the exact trigger is for the increase in spines in motherhood, but we know that the increase goes away with stress,” Leuner said.

She is continuing the work by investigating whether the beneficial effects of motherhood on cognitive functions are also blocked in mothers who are exposed to pregnancy stress as well as whether hormonal factors play a role.

Is LEGO for Girls a Stereotype too far?

The first female minifigure, those 4-centimeter people with the yellow heads, to appear in the January 2012 LEGO catalogue is a doctor ably holding up the back end of a stretcher with her male colleague in a new ambulance set.

Unfortunately, she doesn’t show up until page 12 of the catalogue, after dozens upon dozens of male ninjas, firefighters and all manner of villains. This is the paradox of LEGO for parents, especially parents of girls.

Lego, the famous Danish toy maker could provide an oasis from the anachronistic gender stereotypes so rampant these days, especially in its City line, where women might be employed in all sorts of capacities, as they are in real life and yet the fantasy lines such as Ninjago, Kingdoms, Hero Factory, and of course, Star Wars, are relentlessly male, with the rare exception of Princess Leia.

According to a recent article in Bloomberg Businessweek, focusing on boys was a specific business decision to get the LEGO Group out of a major financial crisis back in 2004 when they were losing $1 million a day. The strategy worked so well that revenues increased by 105% from 2006 to 2010, and sales in the U.S. topped $1 billion for the first time last year.

BBC Radio 4: Woman's Hour Podcast; dyslexia - can it be an advatage

Can dyslexia sometimes be an advantage? Presented by Jane Garvey.

Click on the link to hear the Radio 4 podcast
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Paraplegic Woman walks again with aid of Exoskeleton

It’s been almost twenty years since Amanda Boxtel stood on her own two feet due to a freak skiing accident in Colorado, but today she’s up and walking again thanks to an exoskeleton from Ekso Bionics.

As Boxtel notes, this is only the first step in exoskeleton technology and someday, she hopes to dance again, cheek-to-cheek.

Fishing games gone wrong: Trial-and-error behind important cause of female infertility

When an egg cell is being formed, the cellular machinery which separates chromosomes is extremely imprecise at fishing them out of the cell's interior, scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have discovered.

The unexpected degree of trial-and-error involved in this process could explain why errors in the number of chromosomes in the egg cell are the leading cause of miscarriages and severe congenital diseases such as trisomies like Down's syndrome, as well as an important cause of female infertility.

he findings are published online in Cell.

Our cells have two copies of each chromosome, one inherited from our mother and the other from our father. An oocyte, the cell that matures into an egg cell, has to discard half of its chromosomes, keeping only the maternal or paternal copy of each. To do so, fibres called microtubules act like fishing lines, attaching themselves to chromosomes and reeling them in to opposite sides of the cell. However, the EMBL scientists discovered that these microtubules are much worse fishermen than expected, often incorrectly hooking onto a chromosome and having to let it go again.

"We saw that they have to go through several tries before getting the connection right," says Jan Ellenberg, who led the work at EMBL: "overall, 90% of all chromosomes get connected in the wrong way, and therefore the pathway that corrects these errors is heavily used."

The difficulty in the oocyte is that two fishing lines cast from opposite sides of the cell have to attach themselves to the maternal and paternal copies of the same chromosome. Each of those chromosome copies has a protein structure called a kinetochore, which acts like the magnet in a toy fish, providing the spot for the microtubule 'fishing lines' to attach themselves. The EMBL scientists were the first to track the movement of all kinetochores throughout the whole 8 hours of the first round of cell division in mouse egg cells, which are very similar to human ones.

"We were able to get very high resolution images for extended periods of time," explains Tomoya Kitajima, who carried out the work, "because our lab developed a microscope that automatically searches for chromosomes, zooms in, and scans only the area they are in, doing very little damage to the cell."

Testosterone reduces the empathetic responses in Women

Testosterone - Lauded by some and viewed with suspicion by others, few people have a completely neutral view of the hormone that separates boys from girls.

According to the extreme male brain theory of autism, the organising effects of testosterone on the brain in utero, and its ongoing shaping of social behaviors throughout life, explains why men exhibit more aggressive, risk-taking behaviour than women do.

It may also account for the social intelligence deficits of people with autism and the skewed gender ratio of the disorder.

A new study shows that even a little bit of testosterone administered under the tongue can cause a woman to show less empathy — to behave, in other words, more like a man.

This is especially true, researchers say, when a woman has been exposed to higher-than-average levels of testosterone as a fetus.

The 2D:4D Finger Test
One increasingly accepted marker of fetal androgen exposure is the 2D:4D ratio, comparing the length of the index finger to that of the ring finger on the right hand. In women, the ring finger is typically longer than the index finger, whereas in men, or in individuals with high fetal testosterone exposure, the two fingers are of nearly identical length.

Exposure to lower testosterone levels in utero, as inferred by a higher 2D:4D ratio, may protect men from prostate cancer. Researchers have also reported lower 2D:4D ratios in children with autism and in their parents and siblings.

In the study, researchers administered a single 0.5 mg dose of testosterone to 16 young women between 20 and 25 years of age in one session, and a single dose of placebo in a second session 48 hours later. The women experienced a ten-fold increase in blood testosterone levels 15 minutes after intake, with the levels returning to baseline in about an hour and a half.

During that time, the participants took a test of cognitive empathy called Reading the Mind in the Eyes, which asks them to infer the emotions expressed in a photograph of a pair of eyes. Interestingly, 75 percent of the women in the study achieved lower scores on the test after testosterone than after placebo.

When the researchers compared the women's 2D:4D ratios, as computed from scans of their right hands, they found something even more interesting: the women with the lowest 2D:4D ratios (highest fetal testosterone exposure) showed the most significant decrease in empathy as measured by the test.

This may not be not a slam-dunk for the extreme male brain theory, but the results jibe with other studies that have found a continuum of social cognition abilities.

Effects of Cigarette Smoking and Family History Of Alcoholism Linked To Love Of Sweets Among Women

Effects of Cigarette Smoking and Family History Of Alcoholism Linked To Love Of Sweets Among Women

Despite the greater health risks, women derive more pleasure than men from the smell and taste of cigarettes, are more likely to smoke as a way to reduce stress and feelings of depression, and use smoking as a diet tool. In fact, many women who try to quit smoking often relapse because of concerns about gaining weight.

"Cigarette smoking and having a family history of alcoholism had different effects on sweet-taste perception and food cravings," said Julie A. Mennella, a senior researcher at Monell and coauthor of the study. "Women who smoked cigarettes were less sensitive to sweet taste than women who never smoked.

This means that women who smoke required higher concentrations of a sweet solution in order to detect sweet taste; we also found that the more years a woman has smoked cigarettes, the less sensitive she will be to sweet taste." Whether the reduced sensitivity for sweet tastes helps smokers control their weight is an important question that needs further study, she added.

"Distortions of perception of sweet taste and craving for sweets have been reported in patients with various psychiatric conditions -- depression, substance abuse, eating disorders, premenstrual syndrome, several forms of obesity etc.