Brain’s Magnetic Fields Reveal Language Delays in Autism

PHILADELPHIA and CHICAGO, Dec. 1 /PRNewswire-USNewswire/ — Faint magnetic
signals from brain activity in children with autism show that those children
process sound and language differently from non-autistic children. Identifying
and classifying these brain response patterns may allow researchers to more
accurately diagnose autism and possibly aid in developing more effective
treatments for the developmental disorder.

Timing appears to be crucial. “Children with autism respond a fraction of
a second more slowly than healthy children to vowel sounds and tones,” said
study leader Timothy Roberts, Ph.D., vice chair of radiology research and
holder of the Oberkircher Family Endowed Chair in Pediatric Radiology at The
Children’s Hospital of Philadelphia. Roberts used a technology called
magnetoencephalography (MEG), which detects magnetic fields in the brain, just
as electroencephalography (EEG) detects electrical fields.

Roberts presented his findings today at the annual meeting of the
Radiological Society of North America in Chicago. “The brain’s electrical
signals generate tiny magnetic fields, which change with each sensation, and
with communication among different locations in the brain,” he added.

Roberts is working to develop “neural signatures” that can link recorded
brain activity to particular behaviors in children with autistic spectrum
disorders (ASDs), which are characterized by impaired development in
communications and social functioning. “Our hypothesis is that speech and
other sounds come in too fast for children with ASDs, and their difficulties
in processing sound may impair their language and communication skills,” said
Roberts.

Physicians already use MEG to map the locations of abnormal brain activity
in epilepsy, but the technology Roberts used is one of the few MEG machines
available in a dedicated pediatric facility. In the current study, the
researchers evaluated 64 children aged six to 15 at The Children’s Hospital of
Philadelphia. Thirty children had ASDs, the rest were age-matched, typically
developing control subjects.

The MEG machine has a helmet that surrounds the child’s head. The
researchers presented a series of recorded beeps, vowels and sentences. As the
child’s brain responded to each sound, noninvasive magnetic detectors in the
machine analyzed the brain’s changing magnetic fields.

When sounds were presented, the MEG recorded a delay of 20 milliseconds
(1/50 of a second) in the brain’s response for children with ASDs, when
compared with healthy control subjects. “This delay indicates that auditory
processing is abnormal in children with autism, and may lead to a cascade of
delay and overload in further processing of sound and speech,” said Roberts.
“Further research may shed light on how this delay in processing sounds may be
related to interconnections among parts of the brain.” Other testing,
measuring a response to mismatched or changed sounds, found longer delays, up
to 50 milliseconds (1/20 of a second).

Because autism disorders range across a spectrum of functional abilities,
explained Roberts, neural signatures based on brain responses may allow
clinicians to more accurately diagnose which subtype of ASD an individual
patient has. Such diagnoses may be possible at an earlier age if future
studies show that such signatures are detectable in infancy-at younger ages
than in the children involved in the current study. “Earlier diagnosis of ASDs
may allow clinicians to intervene earlier with possible treatments,” said
Roberts.

Furthermore, added Roberts, if a patient’s neural signature overlaps with
that found in another neurological condition, such as epilepsy or attention-
deficit hyperactivity disorder, for which a treatment exists, that patient may
benefit from such a treatment.

The National Institutes of Health, the Nancy Lurie Marks Family
Foundation, and the Jeffrey and Christina Lurie Family Foundation provided
funding support for the study. Co-authors with Roberts were J. Christopher
Edgar, Ph.D.; Deborah M. Zarnow, M.D.; and Susan E. Levy, M.D.; all of
Children’s Hospital.

About The Children’s Hospital of Philadelphia: The Children’s Hospital of
Philadelphia was founded in 1855 as the nation’s first pediatric hospital.
Through its long-standing commitment to providing exceptional patient care,
training new generations of pediatric healthcare professionals and pioneering
major research initiatives, Children’s Hospital has fostered many discoveries
that have benefited children worldwide. Its pediatric research program is
among the largest in the country, ranking second in National Institutes of
Health funding. In addition, its unique family-centered care and public
service programs have brought the 430-bed hospital recognition as a leading
advocate for children and adolescents. For more information, visit
http://www.chop.edu.

Contact: Rachel Salis-Silverman

             Phone: (267) 426-6063
             Salis@email.chop.edu

SOURCE The Children’s Hospital of Philadelphia