FASD impacts brain development throughout childhood and adolescence

Highlighted areas are some of the white matter tracts the research group studied. Credit: U of A

Medical researchers at the University of Alberta recently published findings showing that brain development is delayed throughout childhood and adolescence for people born with Fetal Alcohol Spectrum Disorder (FASD).

Christian Beaulieu and Carmen Rasmussen, the two primary investigators in the research study, recently published the results of their work in the peer-reviewed journal, The Journal of Neuroscience.

Carmen Rasmussen

Their team scanned 17 people with FASD, and 27 people without the disorder, who were between 5 and 15 years old.

Each participant underwent two to three scans, with each scan taking place two to four years apart.

This is the first research study involving multiple scans of the same FASD study participants.

Researchers used an advanced MRI method that examines white matter in the brain. White matter forms connections between various regions of the brain and usually develops significantly during childhood and adolescence.

Those who took part in the study were imaged multiple times, to see what kinds of changes occurred in brain development as the participants aged.

Those without the disorder had marked increases in brain volume and white matter – growth that was lacking in those with FASD.

However, the advanced MRI method revealed greater changes in the brain wiring of white matter in the FASD group, which the authors suggest may reflect compensation for delays in development earlier in childhood.

Sarah Treit

"These findings may suggest that significant brain changes happened earlier in the study participants who didn't have FASD," says the study's first author, Sarah Treit, who is a student in the Centre for Neuroscience at the U of A.

"This study suggests alcohol-induced injury with FASD isn't static – those with FASD have altered brain development, they aren't developing at the same rate as those without the disorder. And our research showed those with FASD consistently scored lower on all cognitive measures in the study."

Treit said the research team also made other important observations. Children with FASD who demonstrated the greatest changes in white matter development also made the greatest gains in reading ability – "so the connection seems relevant."

Christian Beaulieu

And those with the most severe FASD showed the greatest changes in white matter brain wiring. Scans also confirmed those with FASD have less overall brain volume – this issue neither rectified itself nor worsened throughout the course of the study.

The team is continuing their research in this area, in hopes of finding a biomarker for FASD, and to examine how the brain changes from adolescence into adulthood in those with the disorder.

The advanced MRI imaging the team used can pinpoint brain damage present in those with FASD, and could one day guide medical interventions for those with the disorder, which affects one in every 100 Canadians.

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Foetal Alcohol Exposure affects childhood development

Children exposed to alcohol during fetal development exhibit changes in brain structure and metabolism that are visible using various imaging techniques, according to a new study being presented today at the annual meeting of the Radiological Society of North America (RSNA).

Alcohol use by expectant mothers can lead to problems with the mental and physical development of their children—a condition known as fetal alcohol syndrome.

Research suggests an incidence of 0.2 to 1.5 per 1,000 live births, according to the Centers for Disease Control and Prevention.

Costs for care of individuals affected by fetal alcohol syndrome in the U.S. have been estimated at $4 billion annually.

Advancements in magnetic resonance imaging (MRI) are affording unprecedented insights into the effects of alcohol on the central nervous systems of children whose mothers drank alcohol during their pregnancy.

Recently, researchers in Poland used three different MRI techniques to better define these effects.

The study group included 200 children who were exposed to alcohol during their fetal stage and 30 children whose mothers did not drink while pregnant or during lactation.

Researchers used MRI to evaluate the size and shape of the corpus callosum, the bundle of nerve fibers that forms the major communication link between the right and left halves of the brain, in the two groups.

Prenatal alcohol exposure is the major cause of impaired development or complete absence of the corpus callosum.

The MRI results showed statistically significant thinning of the corpus callosum in the children exposed to alcohol compared with the other group.

“These changes are strongly associated with psychological problems in children,” said Andrzej Urbanik, M.D., chair of the Department of Radiology at Jagiellonian University in Krakow, Poland.

Dr. Urbanik and colleagues also used diffusion weighted imaging (DWI) to study six areas of the central nervous system in the children. DWI maps the diffusion process of water and can be a more sensitive means than traditional MRI for detecting tissue abnormalities.

Children in the alcohol group exhibited statistically significant increases in diffusion on DWI compared with the other children.

“The increase of diffusion indicates neurological disorders or damage to the brain tissue,” Dr. Urbanik said.

To noninvasively study metabolism in the brains of the children, the researchers used proton (hydrogen) magnetic resonance spectroscopy (HMRS), a common adjunct to structural MRI studies. HMRS results showed a complex collection of metabolic changes.

“In individual cases, we found a high degree of metabolic changes that were specific for particular locations within the brain,” Dr. Urbanik said.