Non-invasive hypothalamic stimulation offers hope for dementia treatment
A new form of deep brain stimulation could form the basis for treating dementia without surgery. The study is published in the journal Nature Neuroscience.Researchers from Imperial College London have completed a successful human safety trial of high-frequency stimulation of neurons in the hippocampus - the area responsible for forming, organizing and retrieving memories. This non-invasive and painless treatment is now being tested on older people with cognitive impairment as a potential way to improve memory and function loss caused by Alzheimer's disease and other forms of dementia.
Scientists have investigated brain stimulation using the Time Interference (TI) technique. The technique involves non-invasively targeting neurons with two high-frequency electric fields. The beams are tuned to 2000 Hz and 2005 Hz, and where they intersect, a third current of 5 Hz is created. This current is the key current: it has the same frequency at which brain cells are triggered.
In the experiment, the 5 Hz current stimulated neurons in the hippocampus without affecting healthy brain tissue in other areas. The researchers began with postmortem tests to see if the electric fields would have an accurate effect on the hippocampus. TI stimulation was then administered to 20 healthy volunteers. During the treatment, participants memorized pairs of faces and names. Functional magnetic resonance imaging (fMRI) showed that TI selectively affected specific hippocampal activity directly related to memory.
By extending TI stimulation to 30 minutes, the scientists noticed that memories formed during stimulation were retained when tested again, although the rate of forgetting was similar in the experimental and control groups. The researchers are continuing the trials now with older adults with signs of developing dementia.
Scientists hope that under the influence of such stimulation, sick neurons will begin to act again, and mitochondria damaged by Alzheimer's, which provide nutrition to cells, will restore work.