Imaging How we Think

Functional brain imaging may diagnose Alzheimer's

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) The vast mysteries of the brain are continuing to be unraveled. Now scientists are able to identify someone's thought processes by using advanced MRI technology.

Various areas of the brain "talk" to each other. Identifying breakdowns in this complex communication network may lead scientists to be able to diagnose Alzheimer's disease and other brain disorders.

"Imaging thought patterns may be used to diagnose Alzheimer's."

In a number of experiments, researchers used functional magnetic resonance imaging (fMRI) to pinpoint active regions of the brain where nerve cells were firing rapidly. The study was led by Michael Greicius, MD, assistant professor of neurology and neurological sciences at Stanford University.

The technology picked up if participants were relaxing, singing to themselves, performing mental math calculations or remembering the day's events. So fMRI may help scientists learn more about how the brain operates in its natural, free-flowing movement.

Previous studies have asked participants to perform a specific mental task in a particular timeframe. Grecius' experiments eliminated the controls to look at how a person normally thinks.

The study involved a group of 14 healthy women and men, each of whom had four 10-minute scans. Participants weren't given any instructions about what to think during the scans.

The scans documented that different thought processes appeared in different networks or regions talking with each other. Researchers were able to correctly identify the mental state with 85 percent accuracy.

When Alzheimer's disease is present, as an example, the network linked to memory doesn't work properly, and this shows up in brain regions that no longer fire in a normal fashion.

This network approach to examining brain function and dysfunction is now being widely used to study both psychiatric and neurological conditions.

Reviewed by: 
Review Date: 
May 31, 2011
Last Updated:
June 2, 2011