A high-tech MRI may be able to detect precisely how brain function changes with lack of sleep. It’s part of a troop study getting underway at the Uniformed Services University of Health Sciences in Bethesda, Maryland.
Researchers will use General Electric’s MRI system Microstructure Anatomy Gradient for Neuroimaging with Ultrafast Scanning ― or MAGNUS ― to watch the brains of both healthy sleepers and the chronically sleep-deprived to see if the process the brain undergoes to clear out “waste” every night is affected by insomnia.
“So, you now have, essentially, a hypothesis that if deep sleep is disrupted, and you’re looking at short naps or going through incomplete stages of sleep ― the question that some researchers asked was, does that pathway become less efficient?” Luca Marinelli, GE’s product leader, told Military Times on Thursday.
The idea is a follow-up from a previous USUHS-GE study using MAGNUS, a head-only system, to look at traumatic brain injury markers in troops that can’t be seen on a regular MRI.
“That was kind of like the pilot, you know, to prove out that the device works,” Marinelli said. “It’s powerful. It gives us insights that we were not able to get with conventional whole-body MRI systems.”
The next step is to interrogate how the sleep disturbances, including those known to accompany TBI, affect the brain’s ability to wash away waste products at the end of the day, the way the lymphatic system does for the body’s other tissues.
The glymphatic pathway in the brain, according to a November release from GE, is basically the body’s way of “clearing your head” during the night, and studies have shown it’s particularly active during deep sleep.
Some studies have shown that active duty troops are regularly getting fewer than six hours of sleep every night — even fewer than that when they’re deployed.
GE is specifically interested in “watchstanders,” Marinelli said, those who have regularly had to stay up all or most of the night as part of their duties, a common occurrence for sailors on ships underway or troops deployed to combat.
Troops and veterans being treated for sleep disturbances are the main recruiting pool, along with some subjects with normal sleep patterns for comparison.
The study, funded by a Defense Department grant, is scheduled to take three years with 75 subjects total. After signing on for the study, Marinelli said, subjects will spend two weeks tracking their sleep, so researchers know whether to consider them for the test group or the control group.
There will then be an acclimation period in which subjects get comfortable while in the machine, followed by one solid sleep session with the MAGNUS, about three hours.
Then they’ll have to see what the data says. If, as they hypothesize, the glymphatic pathway is disrupted by prolonged sleep deprivation, that’s an interesting data point, but there’s no treatment for it.
“So, this is going to be an opportunity to prove it out in a research domain — if that becomes something that you’re able to say, ‘Yep, it works,” Marinelli said. “The hypothesis confirms there is this link that tells me that I can show, for certain people, there is this lack of glymphatic circulation during specific stages of sleep.”
Further study can then be done to see whether restoring sleep through existing treatments — whether medication or other therapy — can get the glymphatic process back to normal.
“If I can tell you that your glymphatic system is not doing as well as it could be … and you respond well to sleep hygiene, then I’m going to prescribe to you get eight hours of sleep a night,” he said. “But if I need to give you a drug that improves your glymphatic system, I don’t have that drug today.”
Diagnostics tend to arrive long before therapeutic tools, he added, but learning about the biological processes around illnesses is often the first step toward developing treatments targeting those misaligned processes.
Meghann Myers is the Pentagon bureau chief at Military Times. She covers operations, policy, personnel, leadership and other issues affecting service members.