Neurophysiological insights into the pathophysiology of REM sleep behavior disorders: A review

Building capacity through open approaches: Lessons from developing undergraduate electrophysiology practicals

Background: Electrophysiology has a wide range of biomedical research and clinical applications. As such, education in the theoretical basis and hands-on practice of electrophysiological techniques is essential for biomedical students, including at the undergraduate level. However, offering hands-on learning experiences is particularly difficult in environments with limited resources and infrastructure. Methods: In 2017, we began a project to design and incorporate electrophysiology laboratory practicals into our Biomedical Physics undergraduate curriculum at the Universidad Nacional Autónoma de México. We describe some of the challenges we faced, how we maximized resources to overcome some of these challenges, and in particular, how we used open scholarship approaches to build both educational and research capacity. Results: We succeeded in developing a number of experimental and data analysis practicals in electrophysiology, including electrocardiogram, electromyogram, and electrooculogram techniques. The use of open tools, open platforms, and open licenses was key to the success and broader impact of our project. We share examples of our practicals and explain how we use these activities to strengthen interdisciplinary learning, namely the application of concepts in physics to understanding functions of the human body. Conclusions: Open scholarship provides multiple opportunities for universities to build capacity. Our goal is to provide ideas, materials, and strategies for educators working in similar resource-limited environments.

RBD and Neurodegenerative Diseases

Rapid eye movement (REM) sleep behavior disorder (RBD) is a sleep disorder characterized by enacting one's dreams during the REM sleep, with most of the dreams being violent or aggressive, so that patients often come to see the doctor complaining hurting themselves or bed partners during sleep. Prevalence of RBD, based on population, is 0.38-2.01 %, but much higher in patients with neurodegenerative diseases, especially synucleinopathies. RBD may herald the emergence of synucleinopathies by decades, such that it may be used as an effective early marker of neurodegenerative diseases. Pharmaceutical treatment of RBD includes clonazepam, melatonin, pramipexole, and some newly reported medications. In this review, we summarized the clinical and PSG features of RBD, the pathophysiology and the therapy of it, focusing on the correlation between neurodegenerative diseases and RBD, in order to emphasize the significance of RBD as an early marker of neurodegenerative diseases.

Reduced thalamic volume in Parkinson disease with REM sleep behavior disorder: volumetric study

INTRODUCTION

REM sleep behavior disorder (RBD) is a common non motor feature of Parkinson's Disease (PD) affecting about half the patients with this disease. Distinct structural brain tissue abnormalities have been reported in several regions modulating REM sleep of the patients with idiopathic RBD. At the present time, there are no conventional MRI studies investigating patients with PD associated with RBD.

METHODS

Herein, we used voxel-based morphometry (VBM) to detect the neuroanatomical profile of PD patients with and without RBD. Optimized VBM was applied to the MRI brain images in 11 PD patients with RBD (PD-RBD), 11 PD patients without RBD (PD) and 18 age-and sex-matched controls. To corroborate VBM findings we used automated volumetric method (FreeSurfer) to quantify subcortical brain regions volumes. Patients and controls also underwent DAT-SPECT and cardiac MIBG scintigraphies.

RESULTS

The VBM analysis showed markedly reduced gray matter volume in the right thalamus of PD-RBD patients in comparison with PD patients and controls. Automatic thalamic segmentation in PD-RBD patients showed a bilaterally reduced thalamic volume as compared with PD patients or controls. All PD patients (with and without RBD) showed a reduced tracer uptake on DAT-SPECT and cardiac MIBG scintigraphies as compared to controls.

CONCLUSIONS

Our findings suggest that the presence of RBD symptoms in PD patients is associated with a reduced thalamic volume suggesting a pathophysiologic role of the thalamus in the complex circuit causing RBD.