Dyslexia and Brain Anatomy: Differences in Men and Women, Boys and Girls

Using MRI, neuroscientists have found significant differences in brain anatomy when comparing men and women with dyslexia to their non-dyslexic control groups. 

Their study is the first to directly compare brain anatomy of females with and without dyslexia. 

Credit: © Lucian Milasan / Fotolia

Using MRI, neuroscientists at Georgetown University Medical Center found significant differences in brain anatomy when comparing men and women with dyslexia to their non-dyslexic control groups, suggesting that the disorder may have a different brain-based manifestation based on sex.

Their study, investigating dyslexia in both males and females, is the first to directly compare brain anatomy of females with and without dyslexia (in children and adults).

Their findings were published online in the journal Brain Structure and Function.

Guinevere Eden

Because dyslexia is two to three times more prevalent in males compared with females, "females have been overlooked," says senior author Guinevere Eden, PhD, director for the Center for the Study of Learning and past-president of the International Dyslexia Association.

"It has been assumed that results of studies conducted in men are generalisable (sic) to both sexes, but our research suggests that researchers need to tackle dyslexia in each sex separately to address questions about its origin and potentially, treatment," Eden says.

Previous work outside of dyslexia demonstrates that male and female brains are different in general, adds the study's lead author, Tanya Evans, PhD.

Tanya Evans

"There is sex-specific variance in brain anatomy and females tend to use both hemispheres for language tasks, while males just the left," Evans says.

"It is also known that sex hormones are related to brain anatomy and that female sex hormones such as estrogen can be protective after brain injury, suggesting another avenue that might lead to the sex-specific findings reported in this study."

The study of 118 participants compared the brain structure of people with dyslexia to those without and was conducted separately in men, women, boys and girls.

• In the males, less gray matter volume is found in dyslexics in areas of the brain used to process language, consistent with previous work. 
• In the females, less gray matter volume is found in dyslexics in areas involved in sensory and motor processing.

The results have important implications for understanding the origin of dyslexia and the relationship between language and sensory processing, says Evans.

Journal Reference:

1. Tanya M. Evans, D. Lynn Flowers, Eileen M. Napoliello, Guinevere F. Eden. Sex-specific gray matter volume differences in females with developmental dyslexia.Brain Structure and Function, 2013; DOI: 10.1007/s00429-013-0552-4

NCLD: 10 Helpful Dyslexia Resources

NCLD offer a number of dyslexia resources at LD.org, but where else can you seek reliable assistance and information about dyslexia?

The following resources will help you learn more about dyslexia and find local help.

You can also use NCLD’s Resource Locator to find programs in your local area. Click on the image to be directed to the NCLD Website.

Dyslexia: Smartphone Apps for Students

NCLD: Reading is the area in which students with dyslexia struggle the most. 

Fortunately, there are many mobile apps that can help.

While we’ve reviewed all of the following ones, and they work well for my daughter who has dyslexia, we also know that “one size (or app) does not fit all.”

You may need to do additional research before finding the app that provides the best “fit” for your child.

Raising Readers Poster: Brains Under Construction

Raising Readers

Reading with your Child: Poster

Natural Reader: Text to Voice Reader

What is NaturalReader?

NaturalReader is a text-to-speech software with natural sounding voices.

This easy-to-use software can read to you any text such as Microsoft Word files, webpages, PDF files, and E-mails.

NaturalReader can also convert any written text into audio files such as MP3 or WAV.

NaturalReader has many other functions, such as audio editor and OCR.

With audio editor, you can be your own sound editor by recording, merging and editing audio files. OCR function works with your scanner to convert printed characters into digital text and it is up to 99% accurate.

This allows you to listen to your printed file or edit it in a word-processing program.

Restless Legs Syndrome (RLS), Insomnia and Brain Chemistry

Johns Hopkins researchers believe they may have discovered an explanation for the sleepless nights associated with Restless Legs Syndrome (RLS), a symptom that persists even when the disruptive, overwhelming nocturnal urge to move the legs is treated successfully with medication.

Neurologists have long believed RLS is related to a dysfunction in the way the brain uses the neurotransmitter dopamine, a chemical used by brain cells to communicate and produce smooth, purposeful muscle activity and movement.

Disruption of these neurochemical signals, characteristic of Parkinson's disease, frequently results in involuntary movements.

Drugs that increase dopamine levels are mainstay treatments for RLS, but studies have shown they don't significantly improve sleep. An estimated 5 percent of the U.S. population has RLS.

Richard P. Allen

The small new study, headed by Richard P. Allen, Ph.D., an associate professor of neurology at the Johns Hopkins University School of Medicine, used MRI to image the brain and found glutamate—a neurotransmitter involved in arousal—in abnormally high levels in people with RLS.

The more glutamate the researchers found in the brains of those with RLS, the worse their sleep. The findings are published in the May issue of the journal Neurology.

"We may have solved the mystery of why getting rid of patients' urge to move their legs doesn't improve their sleep," Allen says.

"We may have been looking at the wrong thing all along, or we may find that both dopamine and glutamate pathways play a role in RLS."

For the study, Allen and his colleagues examined MRI images and recorded glutamate activity in the thalamus, the part of the brain involved with the regulation of consciousness, sleep and alertness.

They looked at images of 28 people with RLS and 20 people without. The RLS patients included in the study had symptoms six to seven nights a week persisting for at least six months, with an average of 20 involuntary movements a night or more.

The researchers then conducted two-day sleep studies in the same individuals to measure how much rest each person was getting.

In those with RLS, they found that the higher the glutamate level in the thalamus, the less sleep the subject got.

They found no such association in the control group without RLS. Previous studies have shown that even though RLS patients average less than 5.5 hours of sleep per night, they rarely report problems with excessive daytime sleepiness.

Allen says the lack of daytime sleepiness is likely related to the role of glutamate, too much of which can put the brain in a state of hyperarousal, day or night.

If confirmed, the study's results may change the way RLS is treated, Allen says, potentially erasing the sleepless nights that are the worst side effect of the condition.

Dopamine-related drugs currently used in RLS do work, but many patients eventually lose the drug benefit and require ever higher doses.

When the doses get too high, the medication actually can make the symptoms much worse than before treatment.

Scientists don't fully understand why drugs that increase the amount of dopamine in the brain would work to calm the uncontrollable leg movement of RLS.

Allen says there are already drugs on the market, such as the anticonvulsive gabapentin enacarbil, that can reduce glutamate levels in the brain, but they have not been given as a first-line treatment for RLS patients.

RLS wreaks havoc on sleep because lying down and trying to relax activates the symptoms. Most people with RLS have difficulty falling asleep and staying asleep.

Only getting up and moving around typically relieves the discomfort. The sensations range in severity from uncomfortable, to irritating, to downright painful.

"It's exciting to see something totally new in the field—something that really makes sense for the biology of arousal and sleep," Allen says.

As more is understood about this neurobiology, the findings may not only apply to RLS, he says, but also to some forms of insomnia.

Allergies among US children increase between 1997 and 2011

For U.S. children aged younger than 18 years, the prevalence of allergies increased from 1997 to 2011, with age, race/ethnicity, and income all affecting the prevalence, according to a May data brief issued by the U.S. Centers for Disease Control and Prevention's National Center for Health Statistics (NCHS).

Kristen D. Jackson, M.P.H., and colleagues from the NCHS in Hyattsville, Md., reviewed data from the National Health Interview Surveys from 1997 to 1999 and from 2009 to 2011 to examine the prevalence of food and skin allergies in U.S. children younger than age 18 years.

According to the report, from 1997 to 2011 there was an increase in the prevalence of food and skin allergies among U.S. children.

The prevalence of skin allergies decreased, while respiratory allergies increased with increasing age.

The prevalence of food, skin, and respiratory allergies was lower among Hispanic children than among other races or ethnicities.

Compared with non-Hispanic white children, non-Hispanic black children were less likely to have respiratory allergies and more likely to have skin allergies.

The prevalence of food and respiratory allergies increased with income level, with children with family income equivalent to 200 percent or more of the poverty level experiencing the highest prevalence of allergy.

"Among children under age 18 years in the United States, the prevalence of food and skin allergies increased from 1997-1999 to 2009-2011," the authors write.

More information: More Information

First aid tips for treating cuts, scrapes and puncture wounds

Spring and summer send lots of people outdoors to enjoy the warm weather, but experts say that also brings an increase in cuts, scrapes and puncture wounds.

In the event of these types of injuries, doctors from Wake Forest Baptist Medical Center advised the first step to take is to assess if the wound is serious.

Taking immediate action can help injuries heal faster and prevent infection. They noted, however, most often these injuries will not require a trip to the emergency department.

"There's definitely an increase in these types of injuries at this time of year," Dr. James Guerrini, medical director of Wake Forest Baptist Health Urgent Care, said in a medical center news release.

"Fortunately, most of them are minor and can be treated effectively at home." Simple first-aid is often enough to treat cuts and scrapes from outdoor activities.

When treating a minor wound, the American College of Emergency Physicians offers the following tips:

• Thoroughly wash your hands with soap and warm water or use an antibacterial cleanser. 
• Apply direct pressure with a clean cloth, paper towel or piece of gauze to the injured area to stop the bleeding. 
• Clean the wound with cool water and mild soap, and gently dry the area. Apply an antibiotic ointment to the wound to reduce the risk for infection. 
• Cover the wound with a sterile bandage. 

"Cuts and scrapes are common, so everybody should know how to deal with them," Guerrini added.

"Proper treatment administered quickly can prevent infection, promote healing and otherwise keep something minor from becoming something major."

In some cases, however, emergency medical attention is required.

The U.S. National Institutes of Health advised seeking urgent care for the following:

• Wounds that are very large or bleeding excessively. 
• Injuries that are on the face or near a bone. 
• Injuries that have caused people to lose feeling or function in the affected area. 
• Injuries caused by a human or animal bite. 
• Wounds caused by a rusty object. 
• Wounds with objects or debris stuck inside. 

A doctor should also be consulted about wounds that do not appear to be healing after 48 hours or injuries that are red, swollen, pus-filled or show other signs of infection.

The experts noted that getting the tetanus vaccine can help protect against the serious bacteria-borne illness that infects the body through cuts and puncture wounds.

They pointed out that protection against tetanus doesn't last a lifetime and adults should get a tetanus booster shot every 10 years.

More information:
A number of Health Care sites provide good information on wounds. Here are a few examples;

• The American Academy of Family Physicians - first-aid tips for cuts and scrapes
• The NIH - cuts and puncture wounds
• The Parent24 site - cuts and wound care

Canadian Researchers Discover Two Parents are often Better Than One

A team of researchers at the University of Calgary's Hotchkiss Brain Institute (HBI) have discovered that adult brain cell production might be determined, in part, by the early parental environment.

The study suggests that dual parenting may be more beneficial than single parenting.

Scientists studied mouse pups that were raised by either dual or single parents and found that adult cell production in the brain might be triggered by early life experiences.

The scientists also found that the increased adult brain cell production varied based on gender. Specifically, female pups raised by two parents had enhanced white matter production as adults, increasing motor coordination and sociability.

Male pups raised by dual parents displayed more grey matter production as an adult, which improves learning and memory.

Samuel Weiss

"Our new work adds to a growing body of knowledge, which indicates that early, supportive experiences have long lasting, positive impact on adult brain function," says Samuel Weiss, PhD, senior author of the study and director of the HBI.

Surprisingly, the advantages of dual parenting were also passed along when these two groups reproduced, even if their offspring were raised by one female.

The advantages of dual parenting were thus passed along to the next generation.

To conduct the study, scientists divided mice into three groups

1. pups raised to adulthood by one female 
2. pups raised to adulthood by one female and one male and 
3. pups raised to adulthood by two females. 

Researchers then waited for the offspring to reach adulthood to find out if there was any impact on brain cell production.

Scientists say that this research provides evidence that, in the mouse model, parenting and the environment directly impact adult brain cell production.

While it's not known at this point, it is possible that similar effects could be seen in other mammals, such as humans.

More information: 
The study is published in the May 1 edition of PLOS ONE. dx.plos.org/10.137… pone.0062701