Drug development for neurodegenerative diseases has been very challenging and largely unsuccessful. Researchers are increasingly looking at alternative therapies, one of which is electrical brain stimulation. This strategy has already been used for a while in humans, for instance to eleviate the motor symptoms in Parkinson's disease patients.

Brain stimulation could also be beneficial to Alzheimer's disease patients, because that disease is also associated with abnormal activity of important brain networks. In animal models, brain stimulation was able to counteract two major hallmarks of Alzheimer's disease: the abnormal build-up of a toxic protein called amyloid-beta, and the activation of microglia, the immune cells of our brain.

Moreover, brain stimulation holds potential to boost the communication between brain cells and the generation of new cells, all of which could slow down neurodegeneration and cognitive decline.

We are developing a new, minimally invasive method to stimulate deep brain networks, especially those involved in memory and cognition. We envision to design a compact, fully portable device, allowing long-term treatment with the new brain stimulation method while the patient is at home.

Brain stimulation alone may not cure neurodegeneration, but it could help to delay the onset of cognitive decline by several years, which would make a crucial difference to millions of people. While our initial focus is on Alzheimer’s disease, such a new brain stimulation tool could also be applied to other neurodegenerative diseases in the future.

• van Boekholdt et al. 2020 (Mol Psychiatry) tDCS peripheral nerve stimulation: a neglected mode of action?
• Asamoah et al. 2019 (Nature Communications) tACS motor system effects can be caused by transcutaneous stimulation of peripheral nerves 
• Khatoun et al. 2019 (Front Neurosci) Investigating the Feasibility of Epicranial Cortical Stimulation Using Concentric-Ring Electrodes: A Novel Minimally Invasive Neuromodulation Method
• Romero et al. 2019 (Nature Communications) Neural effects of transcranial magnetic stimulation at the single-cell level
  In this study led by Peter Janssen, macaque monkeys received transcranial magnetic brain stimulation while they were performing a motor task, revealing insights in the effects of brain stimulation at the single-cell level.