Novel imaging technique shows gray matter increase in brains of autistic children

	Tweet

Using a novel imaging technique to study autistic children, researchers have found increased gray matter in the brain areas that govern social processing and learning by observation. Results of the study conducted at the Fay J. Lindner Center for Autism, North Shore-Long Island Jewish Health System in Bethpage, N.Y., were presented today at the annual meeting of the Radiological Society of North America (RSNA).

“Our findings suggest that the inability of autistic children to relate to people and life situations in an ordinary way may be the result of an abnormally functioning mirror neuron system,” said lead author Manzar Ashtari, Ph.D., from the Children’s Hospital of Philadelphia in Pennsylvania.

Mirror neurons are brain cells that are active both when an individual is performing an action and experiencing an emotion or sensation, and when that individual witnesses the same actions, emotions and sensations in others. First observed in the macaque monkey, researchers have found evidence of a similar system in humans that facilitates such functions as learning by seeing as well as doing, along with empathizing and understanding the intentions of others. Dr. Ashtari’s study found the autistic children had increased gray matter in brain regions of the parietal lobes implicated in the mirror neuron system.

The study included 13 male patients diagnosed with high-functioning autism or Asperger syndrome and an IQ greater than 70 and 12 healthy control adolescents. Average age of the participants was about 11 years. Each of the patients underwent diffusion tensor imaging (DTI), a technique that tracks the movement of water molecules in the brain.

DTI is traditionally used to study the brain’s white matter, as well as the brain fibers. However, Dr. Ashtari’s team applied it to the assessment of gray matter by employing apparent diffusion coefficient based morphometry (ABM), a new method that highlights brain regions with potential gray matter volume changes. By adding ABM to DTI, the researchers can detect subtle regional or localized changes in the gray matter.

In addition to the gray matter abnormalities linked to the mirror neuron system, the results of this study revealed that the amount of gray matter in the left parietal area correlated with higher IQs in the control group, but not in the autistic children.

“In the normal brain, larger amounts of gray matter are associated with higher IQs,” Dr. Ashtari said. “But in the autistic brain, increased gray matter does not correspond to IQ, because this gray matter is not functioning properly.”

The autistic children also evidenced a significant decrease of gray matter in the right amygdala region that correlated with severity of social impairment. Children with lower gray matter volumes in this area of the brain had lower scores on reciprocity and social interaction measures.

“Impairments in these areas are the hallmark of autism spectrum disorders, and this finding may lead to greater understanding of the neurobiological underpinnings of the core features of autism,” said study co-author Joel Bregman, M.D., medical director of the Fay J. Lindner Center for Autism.

Autism is the fastest growing developmental disability in the United States and typically appears during the first three years of life. Children with autism are hindered in the areas of social interaction and communication skills. According to the Centers for Disease Control and Prevention, as many as 1.5 million Americans have autism.

###

Co-authors are S. Nichols, Ph.D., C. McIlree, M.S., L. Spritzer, B.S., A. Adesman, M.D., and B. Ardekani, Ph.D.

This study was supported by The Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System and the National Center for Research Resources/National Institutes of Health.

Note: Copies of RSNA 2007 news releases and electronic images will be available online at RSNA.org/press07 beginning Monday, Nov. 26.

RSNA is an association of more than 41,000 radiologists, radiation oncologists, medical physicists and related scientists committed to excellence in patient care through education and research. The Society is based in Oak Brook, Ill. (RSNA.org)

Editor’s note: The data in these releases may differ from those in the printed abstract and those actually presented at the meeting, as researchers continue to update their data right up until the meeting. To ensure you are using the most up-to-date information, please call the RSNA Newsroom at 1-312-949-3233.

Contact: Linda Brooks

630-590-7762
Radiological Society of North America

RELATED STORIES:
A Drink A Day May Delay Dementia   First-Year Treatment Success Lowers 15-Year Death Risk for Alcoholics   Heavy pot smoking may trigger psychosis: study   Buyer Beware of Psychiatric Genetic Tests   Can Primary Care Doctors Treat Depression?   Chronic Pain Might Contribute to Suicidal Thoughts   Poor mental health harming productivity, says OECD   Visual pattern preference may be indicator of autism in toddlers   The Conflict of Reward in Depression   Are you at risk for depression? A quick family history could tell   Minorities Prefer Counseling to Drugs for Treating Depression   Dementia Care Intervention Eases Burden for Families   One in five Americans mentally ill in past year: study   Stress-induced, high levels of corticotropin-releasing factor might be responsible for binge behavio   Mental illness alone not a trigger for violence

Comments

[ + Post Your Own ]

Now you're in the public comment zone. What follows is not Armenian Medical Network's stuff; it comes from other people and we don't vouch for it. A reminder: By using this Web site you agree to accept our Terms of Service. Click here to read the Rules of Engagement.

There are no comments for this entry yet. [ + Comment here + ]