Brain Scan Might Someday Spot Autism

A type of brain imaging that measures the circuitry of brain connections may someday be used to diagnose autism, new research suggests. Researchers at McLean Hospital in Boston and the University of Utah used MRIs to analyze the microscopic fiber structures that make up the brain circuitry in 30 males aged 8 to 26 with high-functioning autism and 30 males without autism. Males with autism showed differences in the white matter circuitry in two regions of the brain's temporal lobe: the superior temporal gyrus and the temporal stem. Those areas are involved with language, emotion and social skills, according to the researchers.

Based on the deviations in brain circuitry, researchers could distinguish with 94 percent accuracy those who had autism and those who didn't. Currently, there is no biological test for autism. Instead, diagnosis is done through a lengthy examination involving questions about the child's behavior, language and social functioning. The MRI test could change that, though the study authors cautioned that the results are preliminary and need to be confirmed with larger numbers of patients.

"Our study pinpoints disruptions in the circuitry in a brain region that has been known for a long time to be responsible for language, social and emotional functioning, which are the major deficits in autism," said lead author Nicholas Lange, director of the Neurostatistics Laboratory at McLean Hospital and an associate professor of psychiatry at Harvard Medical School. "If we can get to the physical basis of the potential sources of those deficits, we can better understand how exactly it's happening and what we can do to develop more effective treatments."

Slowed Reflexes in Aging Could Be Due to Brain Changes

Breakdowns in brain connections may be the reason why your physical response times slow as you age, a new study has found. The decline occurs in an area of the brain called the corpus callosum, which helps regulate "cross-talk" between the two sides of the brain, said lead author Rachael Seidler, an associate professor in the School of Kinesiology and psychology department at the University of Michigan. Normally, one side of the brain controls movement on the opposite side of the body. For example, the left side of the brain controls movement on the right side of the body.

But when regulation of cross-talk between the two sides of the brain starts to break down with age, both sides of the brain talk simultaneously while one side of the body tries to move, resulting in slower response times, the researchers explained. Seidler and colleagues studied the response times and brain activity of adults aged 65 to 75 as they used computer joysticks, and compared them to a group of 20-25 year olds. They also used a functional MRI to image the blood oxygen levels in different parts of the brain, as a measurement of brain activity in the older group. "The more they recruited the other side of the brain, the slower they responded," Seidler said in a University of Michigan news release.