Abstract
Deep brain stimulation (DBS) has compelling results in the desynchronization of the basal ganglia neuronal activities and thus, is used in treating the motor symptoms of Parkinson's disease (PD). Accurate definition of DBS waveform parameters could avert tissue or electrode damage, increase the neuronal activity and reduce energy cost which will prolong the battery life, hence avoiding device replacement surgeries. This study considers the use of a charge balanced Gaussian waveform pattern as a method to disrupt the firing patterns of neuronal cell activity. A computational model was created to simulate ganglia cells and their interactions with thalamic neurons. From the model, we investigated the effects of modified DBS pulse shapes and proposed a delay period between the cathodic and anodic parts of the charge balanced Gaussian waveform to desynchronize the firing patterns of the GPe and GPi cells. The results of the proposed Gaussian waveform with delay outperformed that of rectangular DBS waveforms used in in-vivo experiments. The Gaussian Delay Gaussian (GDG) waveforms achieved lower number of misses in eliciting action potential while having a lower amplitude and shorter length of delay compared to numerous different pulse shapes. The amount of energy consumed in the basal ganglia network due to GDG waveforms was dropped by 22% in comparison with charge balanced Gaussian waveforms without any delay between the cathodic and anodic parts and was also 60% lower than a rectangular charged balanced pulse with a delay between the cathodic and anodic parts of the waveform. Furthermore, by defining a Synchronization Level metric, we observed that the GDG waveform was able to reduce the synchronization of GPi neurons more effectively than any other waveform. The promising results of GDG waveforms in terms of eliciting action potential, desynchronization of the basal ganglia neurons and reduction of energy consumption can potentially enhance the performance of DBS devices.
Highlights
Parkinson’s disease is associated with a complex variation in neuronal spiking patterns in the basal ganglia such as more observed burst and oscillatory patterns (Levy et al, 2000)
Where I(t) is the Deep brain stimulation (DBS) current waveform, Z(t) is the constant impedance set to 1 k, W is the width of the waveform used and M is the number of misses in eliciting an action potential
The results of this study show how modification of DBS waveforms in the network of the basal ganglia can be beneficial in comparison with standard rectangular DBS used in surgeries
Summary
Parkinson’s disease is associated with a complex variation in neuronal spiking patterns in the basal ganglia such as more observed burst and oscillatory patterns (Levy et al, 2000). Experimental recordings of patients with Parkinson’s disease (PD) show an increase in burst firing patterns and synchronization in the Sub Thalamic Nucleus (STN) and Globus Pallidus inturnus (GPi) while a decrease in the firing rate of Globus Pallidus externus (GPe; Bergman et al, 1994; Nini et al, 1995; Wichmann et al, 1999). This synchronization happening in the beta range might be a source to intensify motor symptoms of PD (Brown, 2007; Rivlin-Etzion et al, 2010). The underlying mechanism remains unclear. Tang et al (2016) constructed a minimal neuronastrocyte network model by connecting a neurons chain and an astrocytes chain to investigate the local propagation of abnormal firings
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
