New ways to measure brain activity could help people with multiple sclerosis

Researchers at the Human Brain Project have developed a new method to calculate the delay
in signal propagation in the brains of multiple sclerosis patients.
Multiple sclerosis is a chronic inflammatory disease that affects more than 2 million people
worldwide.
Researchers at the Institute of Neuroscience Systèmes in Marseille, France, the University of Naplespatnop in Italy and the University of Caserta Campania published their findings in the Journal of
Neuroscience.

In multiple sclerosis, the body's immune cells attack myelin, an insulating sheath
that covers all neurons.
Myelin acts like the plastic of insulated cables, causing the current to travel faster
.
Damage to the myelin layer in the brain causes electrical signals to slow down, translating into delayed communication between brain regions and reduced or impaired
capacity.
Measuring the precise effects of spinal cord injuries can help doctors provide personalized treatment
to patients.

This is more difficult than multiple sclerosis: "The disease is a diagnostic paradox," explains
Pierpaolo Sorrentino, lead author of the study.
Some patients have an MRI scan showing extensive degeneration of myelin without corresponding damage, while others have little to no noticeable damage but still have considerable problems
.
Often, we can't judge
just by scanning.
"Stimulating the brain to measure real-time latency between regions is also ineffective when trying to estimate the delay of many brain connections (not just one): the signal ends up becoming too cluttered to be a reliable indicator
of propagation.
"

Instead, the researchers developed a method to measure delay that does not involve direct stimulation but instead uses an avalanche of neurons (bursts of activity that occur in cascades)
that spread spontaneously in the brain.
"These spontaneous bursts of activity can be used to measure the time it takes for signals to cross the white matter tract connecting any two brain regions, and then compare
them to a healthy control group without any myeloid damage," Sorrentino said.
"By not directly interfering with the signal, we can estimate the delay between most brain regions in a matter of minutes and then integrate it with the results shown by the MRI scan
.
"

In addition to providing treatment information, the method can be used to refine the patient's virtual brain model, further increasing the level of
personalization.
Large-scale brain modeling often assumes a constant velocity of signals across the edges, but that's not entirely true
even in healthy brains.
Sorrentino concludes, "We are now able to add time delay factors to these simulations to improve the diagnostic and predictive tools
available to physicians and patients.
"