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Choubdar, H.

Publications and source records attributed to Choubdar, H..

2 recordsLinked to original sources

Cortical spectral rebalancing underlies pregabalin's efficacy in restless legs syndrome

Restless legs syndrome afflicts nearly half of all patients with end-stage renal disease, imposing profound burdens through relentless insomnia and functional decline. Dopaminergic agents--the established first-line therapy--trigger augmentation, a paradoxical intensification of symptoms that leaves patients worse than when they began treatment. The resultant therapeutic impasse has left a vulnerable population without effective recourse. Here we demonstrate that pregabalin, an 2{delta} calcium channel ligand with established renal safety, provides robust and sustained symptom relief in a randomized, placebo-controlled trial of dialysis patients with uremic restless legs syndrome. Clinical benefits emerged rapidly and intensified over three months, with pregabalin-treated patients showing more than twofold greater likelihood of categorical improvement in disease severity. In complementary animal electrophysiology experiments, pregabalin distinctively suppressed cortical hyperarousal--a hallmark of restless legs syndrome--by rebalancing low- and high-frequency oscillatory activity patterns, particularly in motor regions. This neural signature closely resembled that of gabapentin, another therapeutically effective 2{delta} ligand, suggesting convergent mechanisms. Beyond establishing pregabalin as an urgently needed alternative to dopaminergic therapy, our results demonstrate that cortical oscillatory profiling can reveal mechanistic convergence among candidate therapeutics, offering a rational preclinical screening strategy for neurological disorders before exposure of high-risk patient populations to experimental interventions. This framework may accelerate therapeutic discovery while reducing clinical trial risks in vulnerable populations.

neuroscience↗

Neural Oscillatory Characteristics of Feedback Associated Activity in Globus Pallidus Interna

Neural oscillatory activities in basal ganglia have prominent roles in cognitive processes on local and global scales. However, the characteristics of high frequency oscillatory activities during cognitive tasks have not been extensively explored in human Globus Pallidus internus (GPi). This study aimed to investigate amplitude and interhemispheric coupling of bilateral GPi high gamma bursts in dystonia and Parkinsons Disease (PD) patients, in on and off medication states, after feedback during the Intra-Extra-Dimension shift (IED) task. Bilateral GPi Local Field Potentials (LFP) activity was recorded via externalized DBS electrodes during the IED task. Inter hemisphere phase synchrony was assessed using Inter-Site Phase Clustering (ISPC). Transient high gamma activity ([~]100-150Hz) was observed immediately after feedback in the dystonia patient. Moreover, these bursts were phase synchronous between left and right GPis with an antiphase clustering of phase differences. In contrast, no synchronous high gamma activity was detected in the PD patient with or without dopamine administration. The off-med PD patient displayed enhanced low frequency clusters ameliorated by medication in the on-med state. Furthermore, an increased low frequency activity was observed after feedback of incorrect trials in both disease states. The current study provides a rare report of antiphase homotopic synchrony in human GPi, potentially related to incorporating and processing feedback information. The absence of these activities in off and on-med PD indicates the potential presence of impaired medication independent circuits related to feedback processing. Together, these findings are helpful in pointing to the potential role of GPis synchronized high frequency activity in cognitive tasks and feedback information processing.

neuroscience↗