Researchers from Wayne State University and the Eunice Kennedy Shriver National
Institute of Child Health and Human Development of the NIH reported the success-
ful mapping of the functional connectivity (FC) networks of fetal brains. Using rest-
ing state functional MRI (fMRI) techniques, the team imaged 25 pregnant women
during the second and third trimesters. With these techniques, researchers are for the
first time able to observe the networks within the brain as they develop.
The team hopes that such imaging will develop into practical methods of studying
the development of brain disorders, especially those that affect children like autism
and ADHD.
• Connections between the right and left sides of the brain became stronger as fetuses matured.
Several challenges had to be overcome in order to obtain the data, one of the impor-
tant of which was fetal movement. Only data acquired in between movement could
be used, the remaining 41% of the data was discarded. The researchers were able to
map activity in 80 different regions of the brain and measure the levels of connectivi-
ty between the regions.
A collaborative project between Wayne State Univer-
sity and the Perinatology Research Branch of the Eu-
nice Kennedy Shriver National Institute of Child
Health and Human Development of the National In-
stitutes of Health led to this major discovery. The
team, led by neuroscientist Moriah Thomason, Ph.D.,
assistant professor of Pediatrics at the WSU School of Medicine and director of the Perinatal Neural Connectivity Unit of the PRB, applied functional magnetic reso- nance imaging to study when communication or connectivity between areas of the brain emerge during human fetal life. Extremely challenging to perform, the research discovered that connectivity is already present during fetal life and becomes stronger during fetal development.
“Many brain disorders are thought to arise from disrupted communication in brain networks,” Dr. Thomason said. “Autism, ADHD and dyslexia, for example, have all been associated with disrupted brain connections. Therefore, it is of great importance to understand how these networks form and what events can impact the formation of networks and their connectivity.”
The study, “Cross-Hemispheric Functional Connectivity in the Human Fetal Brain,” was published in the Feb. 20 issue of Science Translational Medicine, a journal of the American Association for the Advancement of Science. The key findings of this study are:
assistant professor of Pediatrics at the WSU School of Medicine and director of the Perinatal Neural Connectivity Unit of the PRB, applied functional magnetic reso- nance imaging to study when communication or connectivity between areas of the brain emerge during human fetal life. Extremely challenging to perform, the research discovered that connectivity is already present during fetal life and becomes stronger during fetal development.
“Many brain disorders are thought to arise from disrupted communication in brain networks,” Dr. Thomason said. “Autism, ADHD and dyslexia, for example, have all been associated with disrupted brain connections. Therefore, it is of great importance to understand how these networks form and what events can impact the formation of networks and their connectivity.”
The study, “Cross-Hemispheric Functional Connectivity in the Human Fetal Brain,” was published in the Feb. 20 issue of Science Translational Medicine, a journal of the American Association for the Advancement of Science. The key findings of this study are:
• Short distance connections were more strongly connected than long-range con-
nections in brain networks.
“By studying communication signals of the brain in healthy human fetuses, we are able, for the first time, to observe and measure the formation of these networks at the beginning of life,” Dr. Thomason said. While network connections in adults are well- established, in children, the networks are still developing.
Dr. Thomason’s team pioneered several techniques to overcome the challenges of scanning fetuses without compromising the health and safety of the mother or her child. Researchers obtained functional MRI connectivity diagrams for more than 80 regions in the fetal brain. “When we began (in November 2012), we did not even know if these communication signals could be measured in the human fetus,” Dr. Thomason said.
The study reveals fetuses are forming connections before they’re born, and that these span shorter distances before they expand to connect widely distributed brain areas.
The team will now work to further define the order and timing of how brain net- works are formed in utero, and compare the development of these brain networks in fetuses with disease, illness or unwanted exposures during pregnancy to determine how neural connection development is disrupted.
“A major motivation for this study was to understand the reasons why premature ba- bies are at risk for cerebral palsy and other neurologic disorders,” said Roberto Romero, M.D., D.Med.Sci., chief of the Perinatology Research Branch, which focuses on the prevention of preterm birth and its long-term consequences. “More than half of preterm children require special assistance in the classroom: 20 percent are in spe- cial education and 50 percent repeat at least one grade in high school. We believe that insults (such as “silent” intrauterine infection or fetal oxygen deficiency) can affect the development of brain connectivity in utero, and this accounts for many of these disorders. The study published today is part of ongoing research to determine whether insults during fetal life have an effect on the brain, and how we can prevent long-term consequences.”
The MRI examinations were performed at WSU’s Vainutis Vaitkevicius, M.D. Mag- netic Resonance Research Facility, located at Harper University Hospital in Detroit, under the direction of E. Mark Haacke, Ph.D., a Wayne State University professor of Radiology and Biomedical Engineering. The research was supported in part by the Merrill Palmer Skillman Institute for Child and Family Development, the Kellogg Foundation, the WSU Department of Pediatrics and the NICHD.
“By studying communication signals of the brain in healthy human fetuses, we are able, for the first time, to observe and measure the formation of these networks at the beginning of life,” Dr. Thomason said. While network connections in adults are well- established, in children, the networks are still developing.
Dr. Thomason’s team pioneered several techniques to overcome the challenges of scanning fetuses without compromising the health and safety of the mother or her child. Researchers obtained functional MRI connectivity diagrams for more than 80 regions in the fetal brain. “When we began (in November 2012), we did not even know if these communication signals could be measured in the human fetus,” Dr. Thomason said.
The study reveals fetuses are forming connections before they’re born, and that these span shorter distances before they expand to connect widely distributed brain areas.
The team will now work to further define the order and timing of how brain net- works are formed in utero, and compare the development of these brain networks in fetuses with disease, illness or unwanted exposures during pregnancy to determine how neural connection development is disrupted.
“A major motivation for this study was to understand the reasons why premature ba- bies are at risk for cerebral palsy and other neurologic disorders,” said Roberto Romero, M.D., D.Med.Sci., chief of the Perinatology Research Branch, which focuses on the prevention of preterm birth and its long-term consequences. “More than half of preterm children require special assistance in the classroom: 20 percent are in spe- cial education and 50 percent repeat at least one grade in high school. We believe that insults (such as “silent” intrauterine infection or fetal oxygen deficiency) can affect the development of brain connectivity in utero, and this accounts for many of these disorders. The study published today is part of ongoing research to determine whether insults during fetal life have an effect on the brain, and how we can prevent long-term consequences.”
The MRI examinations were performed at WSU’s Vainutis Vaitkevicius, M.D. Mag- netic Resonance Research Facility, located at Harper University Hospital in Detroit, under the direction of E. Mark Haacke, Ph.D., a Wayne State University professor of Radiology and Biomedical Engineering. The research was supported in part by the Merrill Palmer Skillman Institute for Child and Family Development, the Kellogg Foundation, the WSU Department of Pediatrics and the NICHD.
Figure 1: This fetal functional connectivity map shows connectivity between brain regions that will later process visual information. The statistical group connectivity map for 25 fetuses ages 24-38 weeks is shown in red-yellow hues on a reference MRI anatomical image from a single 32 week fetal study participant. Areas demonstrating the strongest functional connectivity are shown in bright yellow; all colored areas showed statistical connectivity at a threshold of p < .001, corrected for multiple comparisons. The location of the image corresponds to x = 8 in Montreal Neurological Institute coordinate conventions. The data demonstrates that it is possible to study functional brain connections as they form in utero.
