Evaluation of gait termination strategy in individuals with Essential Tremor and Parkinson's disease.

Introduction: Gait termination (GT) is a challenging transitory task involving converting from a dynamic state of motion to a static state. These transitional locomotor tasks are particularly troublesome for populations with postural deficits, i.e.

Advancing Our Understanding of Brain Disorders: Research Using Postmortem Brain Tissue.

It is thought that proliferative potential of neural progenitor cells, from postmortem tissue obtained from idiopathic PD patients, present in the substantia nigra (SN) as well as other brain regions can be maintained in vitro. While they might be lacking in factors required for differentiation into mature neurons, their regenerative potential is undeniable and suggestive that progenitor cells are found endogenously in the diseased brain. Adult stem/progenitor cells exist in several regions within the PD brain and are likely a valuable source of progenitor cells for understanding disease course, as well as useful tools for generating potential cellular and pharmacologic therapies.

Proceedings of the Seventh Annual Deep Brain Stimulation Think Tank: Advances in Neurophysiology, Adaptive DBS, Virtual Reality, Neuroethics and Technology.

The Seventh Annual Deep Brain Stimulation (DBS) Think Tank held on September 8th of 2019 addressed the most current: (1) use and utility of complex neurophysiological signals for development of adaptive neurostimulation to improve clinical outcomes; (2) Advancements in recent neuromodulation techniques to treat neuropsychiatric disorders; (3) New developments in optogenetics and DBS; (4) The use of augmented Virtual reality (VR) and neuromodulation; (5) commercially available technologies; and (6) ethical issues arising in and from research and use of DBS. These advances serve as both "markers of progress" and challenges and opportunities for ongoing address, engagement, and deliberation as we move to improve the functional capabilities and translational value of DBS. It is in this light that these proceedings are presented to inform the field and initiate ongoing discourse.

Parkinson's disease: Diagnosis and appreciation of comorbidities.

Parkinson's disease (PD) is a complex neuropsychiatric disorder that manifests with a variety of motor and nonmotor symptoms. Its incidence increases with age. It is important for clinicians to be able to distinguish symptoms of aging and other comorbidities from those of PD.

Square Biphasic Pulse Deep Brain Stimulation for Parkinson's Disease: The BiP-PD Study.

Background: Conventional Parkinson's disease (PD) deep brain stimulation (DBS) utilizes a pulse with an active phase and a passive charge-balancing phase. A pulse-shaping strategy that eliminates the passive phase may be a promising approach to addressing movement disorders.

Objectives: The current study assessed the safety and tolerability of square biphasic pulse shaping (sqBIP) DBS for use in PD.

Mild cognitive impairment and dementia in motor manifest Huntington's disease: Classification and prevalence.

Objectives: To identify the characteristics and prevalence of mild cognitive impairment in patients with motor-manifest Huntington's disease (HD) and to propose a new mild cognitive impairment (HD-MCI) classification for HD.

Methods: We included 307 motor-manifest HD participants from the ENROLL-HD study who completed the evaluation in four neurocognitive domains including executive functions, processing speed, language, and memory. Cognitive impairment in each domain was determined by age- and education-adjusted cutoffs (> 1.

A novel approach to study markers of dopamine signaling in peripheral immune cells.

Human monocytes express known markers of dopamine synthesis, storage and clearance, including dopamine transporter (DAT), tyrosine hydroxylase (TH), all subtypes of dopamine receptors and vesicular monoamine transporter 2 (VMAT2). Immunohistochemical and immunofluorescent methodologies have traditionally been employed to determine DAT and TH expression in the CNS, their detection in the blood and specifically in the peripheral monocytes has not been studied by flow cytometry. Flow cytometry assays are widely used in medicine and in basic, preclinical or clinical research to quantify physical and chemical characteristics of target cell populations.

Decreased number of striatal cholinergic interneurons and motor deficits in dopamine receptor 2-expressing-cell-specific Dyt1 conditional knockout mice.

DYT1 early-onset generalized torsion dystonia is a hereditary movement disorder characterized by abnormal postures and repeated movements. It is caused mainly by a heterozygous trinucleotide deletion in DYT1/TOR1A, coding for torsinA. The mutation may lead to a partial loss of torsinA function.

Neurite orientation dispersion and density imaging (NODDI) and free-water imaging in Parkinsonism.

Neurite orientation dispersion and density imaging (NODDI) uses a three-compartment model to probe brain tissue microstructure, whereas free-water (FW) imaging models two-compartments. It is unknown if NODDI detects more disease-specific effects related to neurodegeneration in Parkinson's disease (PD) and atypical Parkinsonism. We acquired multi- and single-shell diffusion imaging at 3 Tesla across two sites.

Acute Effects of Subthalamic Deep Brain Stimulation on Motor Outcomes in Parkinson's Disease; 13 Year Follow Up.

Deep brain stimulation of the Subthalamic nucleus (STN-DBS) is a safe and well-established therapy for the management of refractory motor symptoms in Parkinson's disease (PD). Marked improvement in axial symptoms has been reported in the short term with STN-DBS but questions remain regarding the long-term efficacy of this intervention. We assessed the acute ON and OFF effects of STN-DBS in PD patients who have been treated with STN-DBS for over a decade.

Relationship Between Respiratory Sensory Perception, Speech, and Swallow in Parkinson's Disease.

Background: It has been suggested that sensory impairments contribute significantly to the motor deficits secondary to impaired sensorimotor integration in Parkinson's disease. Speech and swallowing are likely to become disordered in PD, and there is evidence that impaired upper airway sensation also contributes to these disorders.

Objectives: The goal of this study was to investigate the relationship between perception of general respiratory sensation, speech, and swallowing in PD.

Gait worsening and the microlesion effect following deep brain stimulation for essential tremor.

Objective: To investigate the effects of unilateral thalamic deep brain stimulation (DBS) on walking in persons with medication-refractory essential tremor (ET).

Methods: We performed laboratory-based gait analyses on 24 persons with medication-refractory ET before and after unilateral thalamic DBS implantation. Normal and tandem walking parameters were analysed across sessions (PRE-DBS/DBS OFF/DBS ON) by repeated measures analyses of variance.

A randomized study of botulinum toxin versus botulinum toxin plus physical therapy for treatment of cervical dystonia.

Background: Physical therapy (PT) for cervical dystonia is not well studied, and the underlying physiological effects are not known.

Methods: We enrolled 26 subjects comprising of 16 cervical dystonia and 10 healthy controls for normative physiological data. We randomized cervical dystonia patients who reported suboptimal benefits on botulinum toxin (BoNT) injections to BoNT alone (BoNT arm) or BoNT plus PT (PT-BoNT arm).

Structural brain correlates of fatigue in older adults with and without Parkinson's disease.

Fatigue is one of the most common and disabling nonmotor symptoms seen in Parkinson's disease (PD) and is also commonly seen in healthy older adults. Our understanding of the etiology of fatigue in older adults with or without PD is limited and it remains unclear whether fatigue in PD is specifically related to PD pathology. The objective of this study was thus to determine whether fatigue in PD was associated with structural changes in gray or white matter and explore whether these changes were similar in older adults without PD.

Deep Brain Stimulation at Variable Frequency to Improve Motor Outcomes in Parkinson's Disease.

Introduction: Deep brain stimulation (DBS) with high frequency (HFS) is a well-established therapy for Parkinson's disease (PD); however, low frequency DBS (LFS) may control axial symptoms including freezing of gait (FOG). We conducted a pilot safety and feasibility study to examine if a novel DBS paradigm of variable frequency stimulation (VFS) that combined HFS and LFS would capture a broader set of motor symptoms.

Methods: Four PD patients with bilateral STN DBS and FOG were enrolled.

Ventral Intermediate Nucleus Versus Zona Incerta Region Deep Brain Stimulation in Essential Tremor.

Background: The ventral intermediate nucleus (VIM) is the target of choice for Essential Tremor (ET) deep brain stimulation (DBS). Renewed interest in caudal zona incerta (cZI) stimulation for tremor control has recently emerged and some groups believe this approach may address long-term reduction of benefit seen with VIM-DBS.

Objectives: To compare clinical outcomes and DBS programming in the long-term between VIM and cZI neurostimulation in ET-DBS patients.

Predictors of alcohol responsiveness in dystonia.

Objective: To determine predictors of alcohol responsiveness in a large cohort of patients with dystonia.

Methods: A total of 2,159 participants with dystonia were prospectively enrolled in the cross-sectional Dystonia Coalition multicenter study. Patients with secondary, combined, or confirmed genetic dystonia (total n = 164) or unknown alcohol responsiveness (n = 737) were excluded.

STN vs. GPi deep brain stimulation for tremor suppression in Parkinson disease: A systematic review and meta-analysis.

Objective: To compare subthalamic nucleus (STN) deep brain stimulation (DBS) with globus pallidus interna (GPi) DBS for tremor suppression in Parkinson disease (PD).

Background: DBS is an effective surgical therapy that has been shown to provide significant benefit for motor symptoms in PD. Currently, two main structures targeted to treat motor complications in PD are the STN and GPi.

Non-motor Characterization of the Basal Ganglia: Evidence From Human and Non-human Primate Electrophysiology.

Although the basal ganglia have been implicated in a growing list of human behaviors, they include some of the least understood nuclei in the brain. For several decades studies have employed numerous methodologies to uncover evidence pointing to the basal ganglia as a hub of both motor and non-motor function. Recently, new electrophysiological characterization of the basal ganglia in humans has become possible through direct access to these deep structures as part of routine neurosurgery.

Pallidal deep brain stimulation and intraoperative neurophysiology for treatment of poststroke hemiballism.

Deep brain stimulation is a recognized and effective treatment for several movement disorders. Nevertheless, the efficacy of this intervention on abnormal movements secondary to structural brain pathologies is less consistent. In this report, we describe a case of hemiballism-hemichorea due to a peripartum ischemic stroke-treated with deep brain stimulation of the globus pallidus internus.