Magnetic resonance elastography (MRE) to measure the brain activity in milliseconds

Researchers have discovered a new way to measure brain function in milliseconds using magnetic resonance elastography (MRE). This could help with diagnosing and understanding neurological diseases like Alzheimer's, dementia, multiple sclerosis, or epilepsy.

Currently the speed at which scientists can measure brain function in humans is limited to up to six seconds. However, in paper published in Science Advances, an international team of researchers, have discovered a new way to 'see the brain thinking' within a 100 milliseconds time scale. This signals a major development in the science of tracking brain activity as it could now allow scientists to visualize responses in the brain as they unfold.

The team successfully used a technology called magnetic resonance elastography (MRE) to track brain activity. Lead researcher said: "While the brain is capable of processing signals at very high speeds, functional MRI technology can't follow fast neuronal changes, so we can't 'see the brain think'.

"We've now discovered that MRE technology allows us to see brain activity on a much shorter time scale. This is a fascinating and unprecedented result as it shows that brain tissue changes in quasi real time. It will open a new gateway to understand how the brain is functioning."

While the technique has currently been tested on mice, co- said: "Translation of this technology to humans is straightforward and initial studies are currently underway."

Initially interested in scanning the lungs using MRE, the team switched focus when brain scans showed parts of the brain reacting without reason. They then conducted studies on mice, and found that regions of the brain react under different types of stimulus timing using MRE.

The authors show brain stiffness changes of ~10% in response to repetitive electric stimulation of a mouse hind paw over two orders of frequency from 0.1 to 10 Hz. They demonstrate in mice that regional patterns of stiffness modulation are synchronous with stimulus switching and evolve with frequency. For very fast stimuli (100 ms), mechanical changes are mainly located in the thalamus, the relay location for afferent cortical input.

They are now looking to use MREs to observe brain activity, which they hope will help diagnose and understand neurological diseases like Alzheimer's, dementia, multiple sclerosis, or epilepsy.

https://www.kcl.ac.uk/news/measuring-brain-activity-in-milliseconds