Moving a paralyzed hand with your thoughts – smart prosthetics can do it. In stroke patients, orthoses help create new connections between the brain and the paralyzed muscle, researchers from Tübingen report.
What is being researched at the Institute for Neuromodulation and Neurotechnology at the University Hospital Tübingen sounds a bit like science fiction: about navigating one by one brain attack To improve the paralyzed hand, brain impulses generated by an imagined attempt or movement are transmitted in a very short time to technological means such as robotic orthotics, which allow the paralyzed hand to be opened.
Neuroma reorganization of the brain
In this way, Professor Alireza Grapgis explains, the test subjects felt that their fingers were already moving despite their paralysis, so they weren’t just watching. And: “These tactile impressions create a feedback loop between the brain and the paralyzed muscle,” says the researcher.
Recently the Tübingen researchers were able to demonstrate that after a severe stroke, even very large areas of both cerebral hemispheres are attached to the paralyzed hand. And that these brain regions are larger, the more severely impaired the patient is. Apparently, after a stroke, the brain tries to find everything that suits it on its own neural resources Scientists suspect its activation to overcome paralysis.
Neuroprostheses activate new connections in the brain
In a recent study, Grabage’s team was able to prove one more thing: the previously observed neuroplastic reorganization could be supported by training with an intelligent neuromodulator. The researchers were also able to show exactly where this occurs and how new connections between the brain and the paralyzed muscle are strengthened, that is, new connections are activated.
Neurons in these additional brain regions sync up with neurons in the spinal cord responsible for opening the hand. The higher the strength of this synchronization in the frequency band around 20 Hz, the better clinical successes can be observed later,” the study authors report now in the Journal of Neuroscience.
According to the Institute for Neuromodulation and Neurotechnology, it was established in 2020 to “bring together experts in medicine, neuroscience, medical technology, and computer science under one roof” so that they can jointly develop treatments that truly help those affected. “We’re still at the beginning, but now we understand better the direction we need to look at,” Institute Director Grabagi says.
Stroke patients with hand paralysis wanted
A paralyzed hand is common with strokes. For example, if the left hand is paralyzed, then the right half of the brain has been damaged by a stroke. Because: the impulses of left hemisphere movements are usually controlled by a restricted area in the right hemisphere of the brain and vice versa.
The Institute is still looking for subjects for follow-up studies: Patients with permanent hand paralysis after stroke can register for follow-up studies by sending an email to [email protected] or calling 07071 29 85138.