Deep brain stimulation does not change neurovascular coupling in non-motor visual cortex An autonomic and visual evoked blood flow velocity response study

Background and Purpose In Parkinson s disease (PD) subthalamic nucleus deep brain stimulation (STN-DBS) improves motor function Also an effect on the neurovascular coupling in motor cortex was reported due to a parallel activation of a subthalamic vasodilator area (SVA) To address this issue further we analysed neurovascular coupling in a non-motor area Methods Twenty PD patients selected for bilateral STN-DBS were investigated with functional transcranial Doppler (f-TCD) before and after surgery Hemodynamic responses to visual stimulation were registered in left posterior cerebral artery (PCA) and analysed with a control-system approach (parameters gain rate time attenuation and natural frequency) To exclude autonomic effects of STN-DBS we also addressed spectrum analysis of heart rate and of systolic arterial blood pressure variability and baroreceptor gain Findings in the PD group were compared with healthy age-matched controls Results PD patients showed no neurovascular coupling changes in PCA territory compared to controls and STN-DBS changed neither blood flow regulatory parameters nor autonomic function Conclusions Improvement of vasoregulation in some motor cortical areas after STN-DBS might be related to an Improved neuronal functional rather than indicating an effect on the neurovascular coupling or autonomic function (C) 2010 Elsevier Ltd All rights reserved