NON-INVASIVE BRAIN STIMULATION
Non-invasive brain stimulation is a way to influence the activity of brain cells from the outside - with virtually no side effects. Besides direct effects on neuronal activity, it can also promote neuroplasticity, the ability to form new connections between neurons. This helps to protect the brain against pathology, and build more cognitive reserve.
We investigate the potential of these new techniques in Alzheimer patients. Patient data and virtual brain model simulation are combined to search for optimal treatment strategies, decreasing the burden of patient experiments and unwanted side-effects.
Currently, we are running two stimulation projects: one is the Ex Machina study funded by the Dutch government (ZonMw), where we investigate the mechanism of trancranial direct current stimulation (tDCS) in Alzheimer. In a second study funded by Alzheimer Nederland, we will use transcranial alternating current stimulation (tACS) to target the precuneus region in Alzheimer, a site of early damage and altered activity. Later this year, transcranial magnetic stimulation (TMS) of the precuneus region might be added to our research line.
Virtual neural network-guided optimization of non-invasive brain stimulation in Alzheimer’s disease
Patient-friendly and non-invasive forms of brain stimulation are being investigated as alternative or additional treatments to medication in Alzheimer’s disease, but there is still no general agreement on how to best perform them. Transcranial direct current stimulation (tDCS) is one of these techniques, in which a low electrical current is passed between electrodes placed on the scalp in order to regulate brain activity. In this study, we used a computer model of the Alzheimer’s disease brain to simulate the effects that tDCS would have on brain activity, with the aim of predicting where the electrodes should be placed to see the most beneficial changes in brain activity. We compared 20 different electrode placements, and discovered placing the positive electrode at the back of the head resulted in the best improvement. For example, we saw a general increase in the speed of brain activity and increase in connectivity between brain regions, both of which are reduced in Alzheimer’s disease. We believe that our approach can help guide non-invasive brain stimulation treatments in Alzheimer’s disease and potentially other disorders, while helping keep the burden on patients to a minimum.