Microstimulation in The Brain – Does microdialysis influence the activated tissue volume?

Deep brain stimulation (DBS) has been established as an effective treatment for Parkinson's disease and other movement disor-ders. The stimulation is currently administered using tetrode-macroelectrodes that target the subthalamic nucleus (STN). This often leads to side effects which bias the surrounding ar-eas, e.g. the speech centre. Targeting a spe-cific brain region can better be achieved with micro-stimulation electrodes with directed elec-trical field distribution. Experimental studies showed the effectiveness of microelectrode DBS by comparing neurotransmitter outflow before and after the stimulation. The neurotransmit-ter outflow in close proximity to the stimulation is hereby measured by means of microdialysis. To establish ideal distances and stimulation strength, the electric potential around the stim-ulation electrode and microdialysis membrane were modelled using comsol Multiphysics.