A new study has found that children and adolescents with attention deficit hyperactivity disorder (ADHD) have disrupted connections between different areas of the brain that are evident on resting-state functional magnetic resonance imaging (rfMRI). The results of this research are published online in the journal Radiology.
The findings point to the potential of rfMRI to help provide objectively accurate, early diagnosis of a disorder that affects approximately 5 percent of children and adolescents worldwide.
ADHD is a disorder characterized by age-inappropriate degrees of inattention, hyperactivity and impulsivity. Functional MRI studies, which measure brain activity when a person is focused on a particular task, have implicated the brain's frontostriatal circuit, a collection of neural pathways in the frontal lobe of the brain that helps control behavior. However, the specific brain physiology underlying ADHD remains poorly understood.
For the new study, researchers used rfMRI, a relatively new technique that assesses neural function when the brain is not focused on a specific task. The technique is useful for exploring the brain's functional organization independent of task performance.
The researchers compared rfMRI results in 33 boys with ADHD, ages 6 to 16, with those of 32 similarly aged, healthy controls. They correlated the MRI findings with results from tests of executive function, a term for the set of mental processes involved in planning, organizing, time management and regulating emotions, among other things. People with ADHD often have abnormal executive function.
The results showed that the patients with ADHD had altered structure and function located in areas of the brain like the orbitofrontal cortex, which is primarily involved in the cognitive processing of strategic planning, and the globus pallidus, which is involved in executive inhibitory control.
"Our study suggests that the structural and functional abnormalities in these brain regions might cause the inattention and hyperactivity of the patients with ADHD, and we are doing further analysis on their correlation with the clinical symptoms," said Qiyong Gong, M.D., Ph.D., a neuroradiologist from the Department of Radiology at West China Hospital of Sichuan University in Sichuan, China. "Our preliminary results show the association between imaging findings and symptoms."
The researchers also found abnormalities in the connections between resting-state brain networks associated with executive dysfunction. These abnormalities indicate more widespread brain alterations in ADHD than previously had been shown, Dr. Gong said.
Exploration of the association between brain activity and executive function might be useful in better characterizing patients with ADHD and in understanding the pathophysiology underlying the condition, according to Dr. Gong.
"Our results suggest the potential clinical utility of the rfMRI changes as a useful marker, which may help in diagnosis and in monitoring disease progression and, consequently, may inform timely clinical intervention in the future," he said.
Dr. Gong indicated that larger studies are needed to validate the results. The researchers also plan to study changes in connectivity over time in ADHD patients and explore the potential differences of functional connectivity between the clinical subtypes of ADHD, such as inattentiveness and hyperactivity.
The ADHD study is part of a larger project from Dr. Gong's group at Huaxi MR Research Center of the West China Hospital to explore MRI's diagnostic and prognostic potential in psychiatric disorders.
"Intrinsic Brain Abnormalities in Attention Deficit Hyperactivity Disorder: A Resting-State Functional MR Imaging Study." Collaborating with Dr. Gong were Fei Li, Ph.D., Ning He, M.D., Yuanyuan Li, M.D., Lizhou Chen, M.D., Xiaoqi Huang, Ph.D., Su Lui, Ph.D., Lanting Guo, M.D., and Graham J. Kemp, M.A., D.M.
Radiology is edited by Herbert Y. Kressel, M.D., Harvard Medical School, Boston, Mass., and owned and published by the Radiological Society of North America, Inc.
RSNA is an association of more than 53,000 radiologists, radiation oncologists, medical physicists and related scientists promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill.
For patient-friendly information on MRI, visit RadiologyInfo.org.
Linda Brooks | Eurek Alert!
3-D visualization of the pancreas -- new tool in diabetes research
15.03.2017 | Umea University
New PET radiotracer identifies inflammation in life-threatening atherosclerosis
02.03.2017 | Society of Nuclear Medicine
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy