Unraveling the neural signatures: Distinct pallidal patterns in dystonia subtypes.

Introduction: Dystonia manifests as slow twisting movements (pure dystonia) or repetitive, jerky motions (jerky dystonia). Dystonia can coexist with myoclonus (myoclonus dystonia) or tremor (tremor dystonia). Each of these presentations can have distinct etiology, can involve discrete sensorimotor networks, and may have characteristic neurophysiological signature.

Neuronal activity features of the subthalamic nucleus associated with optimal deep brain stimulation electrode insertion path in Parkinson's disease.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a standard treatment for advanced Parkinson's disease (PD). The precise positioning of the electrode can significantly influence the results of DBS and the overall improvement in the quality of life for PD patients receiving this therapy. We hypothesize that single unit activity (SUA) features can serve as a valid marker of the optimal DBS-electrode insertion trajectory, leading to the most favorable outcome of STN-DBS surgery.

Pallidal multifractal complexity is a new potential physiomarker of dystonia.

Objective: Low-frequency 4-12 Hz pallidal oscillations are being considered as potential physiomarkers for dystonia. We suggest investigating the multifractal properties of pallidal activity as an additional marker.

Methods: We employed local field potentials (LFP) recordings from 23 patients with dystonia who were undergoing deep brain stimulation (DBS) surgery to explore the connection between disease severity and the multifractal characteristics of pallidal activity.

Proprioceptive Modulation of Pallidal Physiology in Cervical Dystonia.

Background: There is a growing body of evidence suggesting that botulinum toxin can alter proprioceptive feedback and modulate the muscle-spindle output for the treatment of dystonia. However, the mechanism for this modulation remains unclear.

Methods: We conducted a study involving 17 patients with cervical dystonia (CD), seven of whom had prominent CD and 10 with generalized dystonia (GD) along with CD.

Does Pallidal Physiology Determine the Success of Unilateral Deep Brain Stimulation in Cervical Dystonia?

Pallidal deep brain stimulation is a well-known surgical treatment for cervical dystonia. The resolution of dystonia typically requires bilateral pallidal stimulation, but in some instances, unilateral stimulation has been successful. In such instances, generally, the stimulated hemisphere was contralateral to the dystonic sternocleidomastoid, but rarely it was ipsilateral.

DYT1 dystonia: Neurophysiological properties of the pallidal activity.

Objectives: The aim of this paper is to find the differences in the physiology of the pallidal neurons in DYT1 and non-DYT1 dystonia.

Methods: We performed microelectrode recording of the single unit activity in both segments of the globus pallidus during stereotactic implantation of electrodes for deep brain stimulation (DBS).

Results: We found a reduced firing rate, reduced burst rate, and increased pause index in both pallidal segments in DYT1.

Effects of neck proprioceptive modulation on pallidal network connectivity in dystonia.

Cervical dystonia (CD) is the third most common movement disorder affecting 1 million people worldwide. Proprioceptive modulation is the hallmark of contemporary therapies for dystonia, but the mechanism for this intervention is unclear. We studied proprioceptive influence on CD by measuring the spontaneous single-neuron responses and local field potentials (LFP) from the globus pallidus interna (GPi) in 17 CD patients (9 isolated CD and 8 with CD as a feature of generalized dystonia).

Excessive α-β Oscillations Mark Enlarged Motor Sign Severity and Parkinson's Disease Duration.

Background: β Oscillations in the subthalamic nucleus (STN) have been proven to contribute to Parkinson's disease (PD), but the exact borders of β subbands vary substantially across the studies, and information regarding heterogeneity of β rhythmic activity is still limited. Recently, α oscillations in the basal ganglia have also become the focus of PD research.

Objectives: The aim was to study rhythmic oscillations in the STN in PD patients to identify different subbands with stable oscillatory peaks within a broad α-β range and to establish their associations with motor symptoms.

Oscillations of pause-burst neurons in the STN correlate with the severity of motor signs in Parkinson's disease.

Background: Oscillatory activity in the subthalamic nucleus (STN) in Parkinson's disease (PD) is under extensive study. While rhythmic features of local field potentials are implicated in the manifestation of PD motor signs, less is known about single unit activity (SUA). SUA parameters inside the STN show significant heterogeneity, and various firing patterns may contribute unequally to PD pathophysiology.

Patients selection for psychiatric neurosurgery: pitfalls and considerations.

Neurosurgical interventions (destructive or neuromodulation) are considered as a therapeutic option for patients with treatment resistant mental disorders. However, the issues of indications and contraindications for psychiatric surgery, method and patient selection remain unresolved. This article discusses possible problems and contradictions in the selection of patients, the need for an interdisciplinary team to work to solve the question of the feasibility of using neurosurgical methods.

Pallidal neuron activity determines responsiveness to deep brain stimulation in cervical dystonia.

Objective: In patients with cervical dystonia we sought for the differences in neuronal behavior of pallidal regions where deep brain stimulation resulted in favorable therapeutic response compared to those where the response was absent.

Methods: We compared single-unit activity of 564 neurons recorded from deep brain stimulation sensitive and non-sensitive regions in 17 cervical dystonia patients.

Results: Globus pallidus internus regions responsive to the deep brain stimulation had lower firing rates and bursting compared to non-responsive areas.

Is there a single beta oscillation band interfering with movement in Parkinson's disease?

Beta oscillations in basal ganglia are considered to contribute to motor dysfunction in Parkinson's disease (PD). However, there is a high variety in frequency borders for beta oscillations between studies, which complicates the comparison and interpretation of results. Here we aimed to study the homogeneity of oscillations in the broad "beta" range (8-30 Hz) and their implication to motor functioning in PD.

Voluntary movements cause beta oscillations increase and broadband slope decrease in the subthalamic nucleus of parkinsonian patients.

Periodic features of local field potentials (LFP) are extensively studied to establish the pathophysiological features contributing to Parkinson's disease (PD). Pathological LFP synchronization in the subthalamic nucleus (STN) was assumed to link with motor signs of PD. Commonly, the association between oscillations and clinical signs is studied while the patients are at rest.

Pallidal Activity in Cervical Dystonia with and Without Head Tremor.

The relationship between two common movement disorders, dystonia and tremor, is controversial. Both deficits have correlates in the network that includes connections between the cerebellum and the basal ganglia. In order to assess the physiological relationship between tremor and dystonia, we measured the activity of 727 pallidal single-neurons during deep brain stimulation surgery in patients with cervical dystonia without head oscillations, cervical dystonia plus jerky oscillations, and cervical dystonia with sinusoidal oscillations.

The role of pallidum in the neural integrator model of cervical dystonia.

Dystonia is the third most common movement disorder affecting three million people worldwide. Cervical dystonia is the most common form of dystonia. Despite common prevalence the pathophysiology of cervical dystonia is unclear.