Objective: To elucidate the electrophysiological changes for executive and inhibitory control of responses in STN-DBS patient subjected to different frequencies of electrical stimulation.

Background: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is the main treatment option for Parkinson’s disease (PD) at an advanced stage. The correct programming of the stimulation parameters is required to achieve the maximum effectiveness. Although high-frequency STN-DBS improves motor functions of patients, it can worsen higher frontal cognitive functions, such as executive functions (monitoring, set-shifting, response-inhibition). A beneficial effect of low-frequency STN-DBS on some frontal cognitive abilities has been suggested [1]. Indeed, a frequency-dependent modulation of cognitive circuits involving the subthalamic nucleus is plausible. Event-related potentials (ERP) involving P300 allow to investigate electrophysiological basis of selective attention and executive functions. Interestingly, the P300 configuration is modulated by STN-DBS [2].

Methods: We studied acoustic and visual P300 in 20 med-off PD patients without dementia during a response inhibition task. The acquisition sequence was randomized on the basis of 3 stimulation frequencies (stim-off; 60Hz; 80Hz; 130Hz). We measured peak latency, amplitude, and topographic distribution of the ERP components. Patients underwent: a) a quantitative EEG for the measurement of the electrical configurations on the surface of the scalp; b) the mental count of high-frequency tones in a randomized sequence of low-frequency tones at high rate of habituation (20/100 ratio); c) a response-inhibition task for sporadic NOGO stimuli (17%) in a randomized sequence of 232 trials.

Results: A selective impairment of inhibitory function in PD patients was found. This deficit was related to impaired inhibitory executive function in the frontal lobe. Different frequencies of electrical stimulation produce different effects in peak latency, amplitude, and topographic distribution of the analyzed components.

Conclusions: The inhibition of action and the prevention of detrimental events are important executive mechanisms in human behavior. The functional and neuropsychological consequences of different DBS stimulation on P300 potentials are supposed to be due to difference in top-down monitoring by frontal attention mechanisms engaged to evaluate incoming stimuli.

References:

1. Wojtecki  L,  Timmermann  L,  Jörgens  S,  Südmeyer  M,  Maarouf M,  Treuer  H,  Gross  J, Lehrke R, Koulousakis A, Voges J, Sturm V, Schnitzler A. Frequency-dependent reciprocal modulation  of  verbal  fluency  and  motor  functions  in  subthalamic  deep  brain  stimulation. Arch Neurol. 2006 Sep;63(9):1273-6.
2. Naskar  S1,  Sood  SK,  Goyal  V.  Effect  of  acute  deep  brain  stimulation  of  the  subthalamic nucleus  on  auditory  event-related  potentials  in  Parkinson’s  disease.  Parkinsonism  Relat Disord. 2010 May;16(4):256-60. 

« Back to 2017 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/deep-brain-stimulation-influences-on-event-related-potentials-p300-in-parkinsons-disease/