Parkinson's disease and pathological oscillatory activity: Is the beta band the bad guy? — New lessons learned from low-frequency deep brain stimulation

Professor Peter Brown is Professor of Experimental Neurology and Director of the Medical Research Council Brain Network Dynamics Unit at the University of Oxford. Prior to 2010 he was a Professor of Neurology at University College London.For decades we have had cardiac pacemakers that adjust their pacing according to demand and yet therapeutic adaptive stimulation approaches for the central nervous system are still not clinically available. Instead, to treat patients with advanced Parkinson’s disease we stimulate the basal ganglia with fixed regimes, unvarying in frequency or intensity. Although effective, this comes with side-effects and in terms of sophistication this treatment approach could be compared to having central heating system on all the time, regardless of temperature. This talk will describe recent steps being taken to define the underlying circuit dysfunction in Parkinson’s and to improve deep brain stimulation by controlling its delivery according to the state of pathological activity.Evidence is growing that motor symptoms in Parkinson’s disease are due, at least in part, to excessive synchronisation between oscillating neurons. Recordings confirm bursts of oscillatory synchronisation in the basal ganglia centred around 20 Hz. The bursts of 20 Hz activity are prolonged in patients withdrawn from their usual medication and the dominance of these long duration bursts negatively correlates with motor impairment. Longer bursts attain higher amplitudes, indicative of more pervasive oscillatory synchronisation within the neural circuit. In contrast, in heathy primates and in treated Parkinson’s disease bursts tend to be short. Accordingly, it might be best to use closed-loop controlled deep brain stimulation to selectively terminate longer, bigger, pathological beta bursts to both save power and to spare the ability of underlying neural circuits to engage in more physiological processing between long bursts. It is now possible to record and characterise bursts on-line during stimulation of the same site and trial adaptive stimulation. Thus far, this has demonstrated improvements in efficiency and side-effects over conventional continuous stimulation, with at least as good symptom control in Parkinsonian patients.

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Low-frequency subthalamic nucleus deep brain stimulation for axial symptoms in advanced Parkinson’s disease

Journal of Neurology ◽

10.1007/s00415-013-6983-2 ◽

2013 ◽

Vol 260 (9) ◽

pp. 2306-2311 ◽

Cited By ~ 59

Author(s):

Christos Sidiropoulos ◽

Richard Walsh ◽

Christopher Meaney ◽

Y. Y. Poon ◽

Melanie Fallis ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Deep Brain Stimulation ◽

Subthalamic Nucleus ◽

Brain Stimulation ◽

Low Frequency ◽

Advanced Parkinson’S Disease ◽

Axial Symptoms ◽

Deep Brain

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Deep Brain Stimulation Frequency of the Subthalamic Nucleus Affects Phonemic and Action Fluency in Parkinson’s Disease

Parkinson s Disease ◽

10.1155/2016/6760243 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Valéria de Carvalho Fagundes ◽

Carlos R. M. Rieder ◽

Aline Nunes da Cruz ◽

Bárbara Costa Beber ◽

Mirna Wetters Portuguez

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Deep Brain Stimulation ◽

Subthalamic Nucleus ◽

Brain Stimulation ◽

High Frequency ◽

Verbal Fluency ◽

Low Frequency ◽

Stn Dbs ◽

Deep Brain

Introduction.Deep brain stimulation of the subthalamic nucleus (STN-DBS) in Parkinson’s disease (PD) has been linked to a decline in verbal fluency. The decline can be attributed to surgical effects, but the relative contributions of the stimulation parameters are not well understood. This study aimed to investigate the impact of the frequency of STN-DBS on the performance of verbal fluency tasks in patients with PD.Methods.Twenty individuals with PD who received bilateral STN-DBS were evaluated. Their performances of verbal fluency tasks (semantic, phonemic, action, and unconstrained fluencies) upon receiving low-frequency (60 Hz) and high-frequency (130 Hz) STN-DBS were assessed.Results.The performances of phonemic and action fluencies were significantly different between low- and high-frequency STN-DBS. Patients showed a decrease in these verbal fluencies for high-frequency STN-DBS.Conclusion.Low-frequency STN-DBS may be less harmful to the verbal fluency of PD patients.

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Theta Oscillations at Subthalamic Region Predicts Hypomania State After Deep Brain Stimulation in Parkinson's Disease

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.797314 ◽

2021 ◽

Vol 15 ◽

Author(s):

Yi-Chieh Chen ◽

Hau-Tieng Wu ◽

Po-Hsun Tu ◽

Chih-Hua Yeh ◽

Tzu-Chi Liu ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Deep Brain Stimulation ◽

Brain Stimulation ◽

Emotional Processing ◽

Motor Impairment ◽

Field Potential ◽

Low Frequency ◽

Patient Specific ◽

Deep Brain

Subthalamic nucleus (STN) deep brain stimulation (DBS) is an effective treatment for the motor impairments of patients with advanced Parkinson's disease. However, mood or behavioral changes, such as mania, hypomania, and impulsive disorders, can occur postoperatively. It has been suggested that these symptoms are associated with the stimulation of the limbic subregion of the STN. Electrophysiological studies demonstrate that the low-frequency activities in ventral STN are modulated during emotional processing. In this study, we report 22 patients with Parkinson's disease who underwent STN DBS for treatment of motor impairment and presented stimulation-induced mood elevation during initial postoperative programming. The contact at which a euphoric state was elicited by stimulation was termed as the hypomania-inducing contact (HIC) and was further correlated with intraoperative local field potential recorded during the descending of DBS electrodes. The power of four frequency bands, namely, θ (4–7 Hz), α (7–10 Hz), β (13–35 Hz), and γ (40–60 Hz), were determined by a non-linear variation of the spectrogram using the concentration of frequency of time (conceFT). The depth of maximum θ power is located approximately 2 mm below HIC on average and has significant correlation with the location of contacts (r = 0.676, p < 0.001), even after partializing the effect of α and β, respectively (r = 0.474, p = 0.022; r = 0.461, p = 0.027). The occurrence of HIC was not associated with patient-specific characteristics such as age, gender, disease duration, motor or non-motor symptoms before the operation, or improvement after stimulation. Taken together, these data suggest that the location of maximum θ power is associated with the stimulation-induced hypomania and the prediction of θ power is frequency specific. Our results provide further information to refine targeting intraoperatively and select stimulation contacts in programming.

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