TY - JOUR A1 - Farinelli, Veronica A1 - Palmisano, Chiara A1 - Marchese, Silvia Maria A1 - Strano, Camilla Mirella Maria A1 - D’Arrigo, Stefano A1 - Pantaleoni, Chiara A1 - Ardissone, Anna A1 - Nardocci, Nardo A1 - Esposti, Roberto A1 - Cavallari, Paolo T1 - Postural control in children with cerebellar ataxia JF - Applied Sciences N2 - Controlling posture, i.e., governing the ensemble of involuntary muscular activities that manage body equilibrium, represents a demanding function in which the cerebellum plays a key role. Postural activities are particularly important during gait initiation when passing from quiet standing to locomotion. Indeed, several studies used such motor task for evaluating pathological conditions, including cerebellar disorders. The linkage between cerebellum maturation and the development of postural control has received less attention. Therefore, we evaluated postural control during quiet standing and gait initiation in children affected by a slow progressive generalized cerebellar atrophy (SlowP) or non-progressive vermian hypoplasia (Joubert syndrome, NonP), compared to that of healthy children (H). Despite the similar clinical evaluation of motor impairments in NonP and SlowP, only SlowP showed a less stable quiet standing and a shorter and slower first step than H. Moreover, a descriptive analysis of lower limb and back muscle activities suggested a more severe timing disruption in SlowP. Such differences might stem from the extent of cerebellar damage. However, literature reports that during childhood, neural plasticity of intact brain areas could compensate for cerebellar agenesis. We thus proposed that the difference might stem from disease progression, which contrasts the consolidation of compensatory strategies. KW - children KW - gait initiation KW - postural control KW - generalized cerebellar atrophy KW - cerebellar vermis hypoplasia KW - progressive ataxia KW - compensatory strategies Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200692 SN - 2076-3417 VL - 10 IS - 5 ER - TY - THES A1 - Palmisano, Chiara T1 - Supraspinal Locomotor Network Derangements: A Multimodal Approach T1 - Störungen des Supraspinalen Lokomotorischen Netzwerks: ein Multimodaler Ansatz N2 - Parkinson’s Disease (PD) constitutes a major healthcare burden in Europe. Accounting for aging alone, ~700,000 PD cases are predicted by 2040. This represents an approximately 56% increase in the PD population between 2005 and 2040, with a consequent rise in annual disease‐related medical costs. Gait and balance disorders are a major problem for patients with PD and their caregivers, mainly because to their correlation with falls. Falls occur as a result of a complex interaction of risk factors. Among them, Freezing of Gait (FoG) is a peculiar gait derangement characterized by a sudden and episodic inability to produce effective stepping, causing falls, mobility restrictions, poor quality of life, and increased morbidity and mortality. Between 50–70% of PD patients have FoG and/or falls after a disease duration of 10 years, only partially and inconsistently improved by dopaminergic treatment and Deep Brain Stimulation (DBS). Treatment-induced worsening has been also observed under certain conditions. Effective treatments for gait disturbances in PD are lacking, probably because of the still poor understanding of the supraspinal locomotor network. In my thesis, I wanted to expand our knowledge of the supraspinal locomotor network and in particular the contribution of the basal ganglia to the control of locomotion. I believe this is a key step towards new preventive and personalized therapies for postural and gait problems in patients with PD and related disorders. In addition to patients with PD, my studies also included people affected by Progressive Supranuclear Palsy (PSP). PSP is a rare primary progressive parkinsonism characterized at a very early disease stage by poor balance control and frequent backwards falls, thus providing an in vivo model of dysfunctional locomotor control. I focused my attention on one of the most common motor transitions in daily living, the initiation of gait (GI). GI is an interesting motor task and a relevant paradigm to address balance and gait impairments in patients with movement disorders, as it is associated with FoG and high risk of falls. It combines a preparatory (i.e., the Anticipatory Postural Adjustments [APA]) and execution phase (the stepping) and allows the study of movement scaling and timing as an expression of muscular synergies, which follow precise and online feedback information processing and integration into established feedforward patterns of motor control. By applying a multimodal approach that combines biomechanical assessments and neuroimaging investigations, my work unveiled the fundamental contribution of striatal dopamine to GI in patients with PD. Results in patients with PSP further supported the fundamental role of the striatum in GI execution, revealing correlations between the metabolic intake of the left caudate nucleus with diverse GI measurements. This study also unveiled the interplay of additional brain areas in the motor control of GI, namely the Thalamus, the Supplementary Motor Area (SMA), and the Cingulate cortex. Involvement of cortical areas was also suggested by the analysis of GI in patients with PD and FoG. Indeed, I found major alterations in the preparatory phase of GI in these patients, possibly resulting from FoG-related deficits of the SMA. Alterations of the weight shifting preceding the stepping phase were also particularly important in PD patients with FoG, thus suggesting specific difficulties in the integration of somatosensory information at a cortical level. Of note, all patients with PD showed preserved movement timing of GI, possibly suggesting preserved and compensatory activity of the cerebellum. Postural abnormalities (i.e., increased trunk and thigh flexion) showed no relationship with GI, ruling out an adaptation of the motor pattern to the altered postural condition. In a group of PD patients implanted with DBS, I further explored the pathophysiological functioning of the locomotor network by analysing the timely activity of the Subthalamic Nucleus (STN) during static and dynamic balance control (i.e., standing and walking). For this study, I used novel DBS devices capable of delivering stimulation and simultaneously recording Local Field Potentials (LFP) of the implanted nucleus months and years after surgery. I showed a gait-related frequency shift in the STN activity of PD patients, possibly conveying cortical (feedforward) and cerebellar (feedback) information to mesencephalic locomotor areas. Based on this result, I identified for each patient a Maximally Informative Frequency (MIF) whose power changes can reliably classify standing and walking conditions. The MIF is a promising input signal for new DBS devices that can monitor LFP power modulations to timely adjust the stimulation delivery based on the ongoing motor task (e.g., gait) performed by the patient (adaptive DBS). Altogether my achievements allowed to define the role of different cortical and subcortical brain areas in locomotor control, paving the way for a better understanding of the pathophysiological dynamics of the supraspinal locomotor network and the development of tailored therapies for gait disturbances and falls prevention in PD and related disorders. N2 - Die Parkinson-Krankheit (PD) stellt in Europa eine große Belastung für das Gesundheitswesen dar. Allein unter Berücksichtigung der Alterung werden bis zum Jahr 2040 etwa 700 000 Fälle von Parkinson prognostiziert. Dies entspricht einer Zunahme der Parkinson-Population um etwa 56 % zwischen 2005 und 2040, was zu einem Anstieg der jährlichen krankheitsbedingten medizinischen Kosten führt. Gang- und Gleichgewichtsstörungen sind ein großes Problem für Morbus-Parkinson-Patienten und ihre Betreuer, vor allem, weil sie mit Stürzen zusammenhängen. Stürze sind das Ergebnis einer komplexen Interaktion von Risikofaktoren. Zu diesen Faktoren gehört das Freezing of Gait (FoG), eine besondere Gangstörung, die durch eine plötzliche und episodische Unfähigkeit gekennzeichnet ist, einen effektiven Schritt zu machen, was zu Stürzen, Mobilitätseinschränkungen, schlechter Lebensqualität und erhöhter Morbidität und Mortalität führt. Zwischen 50 und 70 % der Morbus-Parkinson-Patienten haben nach einer Krankheitsdauer von 10 Jahren FoG und/oder Stürze, die sich durch dopaminerge Behandlung und Tiefe Hirnstimulation (DBS) nur teilweise und uneinheitlich verbessern. Unter bestimmten Bedingungen wurde auch eine behandlungsbedingte Verschlechterung beobachtet. Es gibt keine wirksamen Behandlungen für Gangstörungen bei Morbus Parkinson, was wahrscheinlich auf das noch immer unzureichende Verständnis des supraspinalen lokomotorischen Netzwerks zurückzuführen ist. In meiner Dissertation wollte ich unser Wissen über das supraspinale Bewegungsnetzwerk und insbesondere den Beitrag der Basalganglien zur Steuerung der Fortbewegung erweitern. Ich glaube, dass dies ein wichtiger Schritt auf dem Weg zu neuen präventiven und personalisierten Therapien für Haltungs- und Gangprobleme bei Patienten mit Parkinson und verwandten Erkrankungen ist. Neben Morbus-Parkinson-Patienten wurden in meine Studien auch Menschen mit progressiver supranukleärer Lähmung (PSP) einbezogen. PSP ist ein seltener primär progressiver Parkinsonismus, der in einem sehr frühen Krankheitsstadium durch eine schlechte Gleichgewichtskontrolle und häufige Rückwärtsstürze gekennzeichnet ist und somit ein In-vivo-Modell für eine gestörte Bewegungskontrolle darstellt. Ich habe mich auf einen der häufigsten motorischen Übergänge im täglichen Leben konzentriert, die Initiierung des Gangs (GI). GI ist eine interessante motorische Aufgabe und ein relevantes Paradigma zur Untersuchung von Gleichgewichts- und Gangstörungen bei Patienten mit Bewegungsstörungen, da sie mit FoG und einem hohen Sturzrisiko verbunden ist. Sie kombiniert eine Vorbereitungsphase (d. h. die antizipatorischen posturalen Anpassungen [APA]) und eine Ausführungsphase (den Schritt) und ermöglicht die Untersuchung der Bewegungsskalierung und des Timings als Ausdruck muskulärer Synergien, die einer präzisen und online erfolgenden Verarbeitung von Feedback-Informationen und der Integration in etablierte Feedforward-Muster der motorischen Kontrolle folgen. Durch Anwendung eines multimodalen Ansatzes, der biomechanische Bewertungen und bildgebende Untersuchungen kombiniert, hat meine Arbeit den grundlegenden Einfluss des striatalen Dopamins auf GI bei Patienten mit Parkinson enthüllt. Die Ergebnisse bei Patienten mit PSP untermauerten die grundlegende Rolle des Striatums bei der Ausführung von GI, indem sie Korrelationen zwischen der metabolischen Aufnahme des linken Nucleus caudatus und verschiedenen GI-Parametern aufzeigten. Diese Studie enthüllte auch das Zusammenspiel weiterer Hirnareale bei der motorischen Kontrolle von GI, nämlich des Thalamus, der Supplementary Motor Area (SMA) und des Cingulum-Kortex. Die Beteiligung kortikaler Areale wurde auch durch die Analyse der GI bei Patienten mit Parkinson und FoG nahegelegt. In der Tat fand ich bei diesen Patienten erhebliche Veränderungen in der Vorbereitungsphase des GI, die möglicherweise auf FoG-bedingte Defizite der SMA zurückzuführen sind. Veränderungen der Gewichtsverlagerung, die der Schrittphase vorausgeht, waren bei Morbus-Parkinson-Patienten mit FoG ebenfalls besonders ausgeprägt, was auf spezifische Schwierigkeiten bei der Integration somatosensorischer Informationen auf kortikaler Ebene schließen lässt. Bemerkenswert ist, dass alle Morbus-Parkinson-Patienten ein gut erhaltenes Bewegungs-Timing von GI aufwiesen, was möglicherweise auf eine ebenfalls gut erhaltene und kompensatorische Aktivität des Kleinhirns hindeutet. Haltungsanomalien (d. h. verstärkte Rumpf- und Oberschenkelflexion) standen in keinem Zusammenhang mit GI, was eine Anpassung des motorischen Musters an die veränderten Haltungsbedingungen ausschließt. Bei einer Gruppe von Morbus-Parkinson-Patienten, denen eine DBS implantiert wurde, untersuchte ich die pathophysiologische Funktionsweise des lokomotorischen Netzwerks weiter, indem ich die rechtzeitige Aktivität des subthalamischen Nucleus (STN) während der statischen und dynamischen Gleichgewichtskontrolle (d. h. Stehen und Gehen) analysierte. Für diese Studie habe ich neuartige DBS-Geräte verwendet, die in der Lage sind, Stimulationen abzugeben und gleichzeitig lokale Feldpotentiale (LFP) des implantierten Nucleus Monate und Jahre nach der Operation aufzuzeichnen. Ich konnte eine gehbezogene Frequenzverschiebung in der STN-Aktivität von Morbus-Parkinson-Patienten nachweisen, die möglicherweise kortikale (feedforward) und zerebelläre (feedback) Informationen an mesenzephale Bewegungsbereiche weiterleitet. Auf der Grundlage dieses Ergebnisses habe ich für jeden Patienten eine maximal informative Frequenz (MIF) identifiziert, deren Leistungsänderungen eine zuverlässige Klassifizierung von Steh- und Gehzuständen ermöglichen. Die MIF ist ein vielversprechendes Eingangssignal für neue DBS-Geräte, die LFP-Leistungsmodulationen überwachen können, um die Stimulationsabgabe zeitnah an die laufende motorische Aufgabe (z. B. Gehen) des Patienten anzupassen (adaptive DBS). Insgesamt ist es mir gelungen, die Rolle verschiedener kortikaler und subkortikaler Hirnareale bei der Bewegungskontrolle zu definieren. Dies ebnet den Weg für ein besseres Verständnis der pathophysiologischen Dynamik des supraspinalen Bewegungsnetzwerks und die Entwicklung maßgeschneiderter Therapien für Gangstörungen und Sturzprävention bei Morbus Parkinson und verwandten Erkrankungen. KW - locomotor network KW - gait initiation KW - deep brain stimulation KW - gait analysis KW - movement disorders KW - neural biomarkers KW - parkinson's disease Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266442 ER - TY - JOUR A1 - Pozzi, Nicoló G. A1 - Palmisano, Chiara A1 - Reich, Martin M. A1 - Capetian, Philip A1 - Pacchetti, Claudio A1 - Volkmann, Jens A1 - Isaias, Ioannis U. T1 - Troubleshooting gait disturbances in Parkinson’s disease with deep brain stimulation JF - Frontiers in Human Neuroscience N2 - Deep brain stimulation (DBS) of the subthalamic nucleus or the globus pallidus is an established treatment for Parkinson’s disease (PD) that yields a marked and lasting improvement of motor symptoms. Yet, DBS benefit on gait disturbances in PD is still debated and can be a source of dissatisfaction and poor quality of life. Gait disturbances in PD encompass a variety of clinical manifestations and rely on different pathophysiological bases. While gait disturbances arising years after DBS surgery can be related to disease progression, early impairment of gait may be secondary to treatable causes and benefits from DBS reprogramming. In this review, we tackle the issue of gait disturbances in PD patients with DBS by discussing their neurophysiological basis, providing a detailed clinical characterization, and proposing a pragmatic programming approach to support their management. KW - Parkinson’s disease KW - freezing of gait (FOG) KW - deep brain stimulation (DBS) KW - subthalamic nucleus (STN) KW - globus pallidus pars interna (GPi) KW - pedunculopontine nucleus (PPN) Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-274007 SN - 1662-5161 VL - 16 ER - TY - JOUR A1 - Palmisano, Chiara A1 - Kullmann, Peter A1 - Hanafi, Ibrahem A1 - Verrecchia, Marta A1 - Latoschik, Marc Erich A1 - Canessa, Andrea A1 - Fischbach, Martin A1 - Isaias, Ioannis Ugo T1 - A fully-immersive virtual reality setup to study gait modulation JF - Frontiers in Human Neuroscience N2 - Objective: Gait adaptation to environmental challenges is fundamental for independent and safe community ambulation. The possibility of precisely studying gait modulation using standardized protocols of gait analysis closely resembling everyday life scenarios is still an unmet need. Methods: We have developed a fully-immersive virtual reality (VR) environment where subjects have to adjust their walking pattern to avoid collision with a virtual agent (VA) crossing their gait trajectory. We collected kinematic data of 12 healthy young subjects walking in real world (RW) and in the VR environment, both with (VR/A+) and without (VR/A-) the VA perturbation. The VR environment closely resembled the RW scenario of the gait laboratory. To ensure standardization of the obstacle presentation the starting time speed and trajectory of the VA were defined using the kinematics of the participant as detected online during each walking trial. Results: We did not observe kinematic differences between walking in RW and VR/A-, suggesting that our VR environment per se might not induce significant changes in the locomotor pattern. When facing the VA all subjects consistently reduced stride length and velocity while increasing stride duration. Trunk inclination and mediolateral trajectory deviation also facilitated avoidance of the obstacle. Conclusions: This proof-of-concept study shows that our VR/A+ paradigm effectively induced a timely gait modulation in a standardized immersive and realistic scenario. This protocol could be a powerful research tool to study gait modulation and its derangements in relation to aging and clinical conditions. KW - gait modulation KW - virtual reality KW - obstacle avoidance KW - gait analysis KW - kinematics Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-267099 SN - 1662-5161 VL - 16 ER - TY - JOUR A1 - Isaias, Ioannis U. A1 - Brumberg, Joachim A1 - Pozzi, Nicoló G. A1 - Palmisano, Chiara A1 - Canessa, Andrea A1 - Marotta, Giogio A1 - Volkmann, Jens A1 - Pezzoli, Gianni T1 - Brain metabolic alterations herald falls in patients with Parkinson's disease JF - Annals of Clinical and Translational Neurology N2 - Pathophysiological understanding of gait and balance disorders in Parkinson’s disease is insufficient and late recognition of fall risk limits efficacious followup to prevent or delay falls. We show a distinctive reduction of glucose metabolism in the left posterior parietal cortex, with increased metabolic activity in the cerebellum, in parkinsonian patients 6–8 months before their first fall episode. Falls in Parkinson’s disease may arise from altered cortical processing of body spatial orientation, possibly predicted by abnormal cortical metabolism. KW - Parkionson's disease KW - brain metabolic alterations Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235982 VL - 7 IS - 4 ER - TY - JOUR A1 - Palmisano, Chiara A1 - Brandt, Gregor A1 - Vissani, Matteo A1 - Pozzi, Nicoló G. A1 - Canessa, Andrea A1 - Brumberg, Joachim A1 - Marotta, Giorgio A1 - Volkmann, Jens A1 - Mazzoni, Alberto A1 - Pezzoli, Gianni A1 - Frigo, Carlo A. A1 - Isaias, Ioannis U. T1 - Gait Initiation in Parkinson’s Disease: Impact of Dopamine Depletion and Initial Stance Condition JF - Frontiers in Bioengineering and Biotechnology N2 - Postural instability, in particular at gait initiation (GI), and resulting falls are a major determinant of poor quality of life in subjects with Parkinson’s disease (PD). Still, the contribution of the basal ganglia and dopamine on the feedforward postural control associated with this motor task is poorly known. In addition, the influence of anthropometric measures (AM) and initial stance condition on GI has never been consistently assessed. The biomechanical resultants of anticipatory postural adjustments contributing to GI [imbalance (IMB), unloading (UNL), and stepping phase) were studied in 26 unmedicated subjects with idiopathic PD and in 27 healthy subjects. A subset of 13 patients was analyzed under standardized medication conditions and the striatal dopaminergic innervation was studied in 22 patients using FP-CIT and SPECT. People with PD showed a significant reduction in center of pressure (CoP) displacement and velocity during the IMB phase, reduced first step length and velocity, and decreased velocity and acceleration of the center of mass (CoM) at toe off of the stance foot. All these measurements correlated with the dopaminergic innervation of the putamen and substantially improved with levodopa. These results were not influenced by anthropometric parameters or by the initial stance condition. In contrast, most of the measurements of the UNL phase were influenced by the foot placement and did not correlate with putaminal dopaminergic innervation. Our results suggest a significant role of dopamine and the putamen particularly in the elaboration of the IMB phase of anticipatory postural adjustments and in the execution of the first step. The basal ganglia circuitry may contribute to defining the optimal referent body configuration for a proper initiation of gait and possibly gait adaptation to the environment. KW - gait initiation KW - Parkinson’s disease KW - basal ganglia KW - dopamine KW - base of support KW - anthropometric measurements Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200801 SN - 2296-4185 VL - 8 ER - TY - JOUR A1 - Palmisano, Chiara A1 - Beccaria, Laura A1 - Haufe, Stefan A1 - Volkmann, Jens A1 - Pezzoli, Gianni A1 - Isaias, Ioannis U. T1 - Gait initiation impairment in patients with Parkinson’s disease and freezing of gait JF - Bioengineering N2 - Freezing of gait (FOG) is a sudden episodic inability to produce effective stepping despite the intention to walk. It typically occurs during gait initiation (GI) or modulation and may lead to falls. We studied the anticipatory postural adjustments (imbalance, unloading, and stepping phase) at GI in 23 patients with Parkinson’s disease (PD) and FOG (PDF), 20 patients with PD and no previous history of FOG (PDNF), and 23 healthy controls (HCs). Patients performed the task when off dopaminergic medications. The center of pressure (CoP) displacement and velocity during imbalance showed significant impairment in both PDNF and PDF, more prominent in the latter patients. Several measurements were specifically impaired in PDF patients, especially the CoP displacement along the anteroposterior axis during unloading. The pattern of segmental center of mass (SCoM) movements did not show differences between groups. The standing postural profile preceding GI did not correlate with outcome measurements. We have shown impaired motor programming at GI in Parkinsonian patients. The more prominent deterioration of unloading in PDF patients might suggest impaired processing and integration of somatosensory information subserving GI. The unaltered temporal movement sequencing of SCoM might indicate some compensatory cerebellar mechanisms triggering time-locked models of body mechanics in PD. KW - freezing of gait KW - gait initiation KW - Parkinson’s disease KW - posture KW - segmental centers of mass KW - anthropometric measurement KW - base of support Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-297579 SN - 2306-5354 VL - 9 IS - 11 ER - TY - JOUR A1 - Haufe, Stefan A1 - Isaias, Ioannis U. A1 - Pellegrini, Franziska A1 - Palmisano, Chiara T1 - Gait event prediction using surface electromyography in parkinsonian patients JF - Bioengineering N2 - Gait disturbances are common manifestations of Parkinson’s disease (PD), with unmet therapeutic needs. Inertial measurement units (IMUs) are capable of monitoring gait, but they lack neurophysiological information that may be crucial for studying gait disturbances in these patients. Here, we present a machine learning approach to approximate IMU angular velocity profiles and subsequently gait events using electromyographic (EMG) channels during overground walking in patients with PD. We recorded six parkinsonian patients while they walked for at least three minutes. Patient-agnostic regression models were trained on temporally embedded EMG time series of different combinations of up to five leg muscles bilaterally (i.e., tibialis anterior, soleus, gastrocnemius medialis, gastrocnemius lateralis, and vastus lateralis). Gait events could be detected with high temporal precision (median displacement of <50 ms), low numbers of missed events (<2%), and next to no false-positive event detections (<0.1%). Swing and stance phases could thus be determined with high fidelity (median F1-score of ~0.9). Interestingly, the best performance was obtained using as few as two EMG probes placed on the left and right vastus lateralis. Our results demonstrate the practical utility of the proposed EMG-based system for gait event prediction, which allows the simultaneous acquisition of an electromyographic signal to be performed. This gait analysis approach has the potential to make additional measurement devices such as IMUs and force plates less essential, thereby reducing financial and preparation overheads and discomfort factors in gait studies. KW - electromyography KW - inertial measurement units KW - gait-phase prediction KW - machine learning KW - Parkinson’s disease Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304380 SN - 2306-5354 VL - 10 IS - 2 ER - TY - JOUR A1 - Del Vecchio, Jasmin A1 - Hanafi, Ibrahem A1 - Pozzi, Nicoló Gabriele A1 - Capetian, Philipp A1 - Isaias, Ioannis U. A1 - Haufe, Stefan A1 - Palmisano, Chiara T1 - Pallidal recordings in chronically implanted dystonic patients: mitigation of tremor-related artifacts JF - Bioengineering N2 - Low-frequency oscillatory patterns of pallidal local field potentials (LFPs) have been proposed as a physiomarker for dystonia and hold the promise for personalized adaptive deep brain stimulation. Head tremor, a low-frequency involuntary rhythmic movement typical of cervical dystonia, may cause movement artifacts in LFP signals, compromising the reliability of low-frequency oscillations as biomarkers for adaptive neurostimulation. We investigated chronic pallidal LFPs with the Percept\(^{TM}\) PC (Medtronic PLC) device in eight subjects with dystonia (five with head tremors). We applied a multiple regression approach to pallidal LFPs in patients with head tremors using kinematic information measured with an inertial measurement unit (IMU) and an electromyographic signal (EMG). With IMU regression, we found tremor contamination in all subjects, whereas EMG regression identified it in only three out of five. IMU regression was also superior to EMG regression in removing tremor-related artifacts and resulted in a significant power reduction, especially in the theta-alpha band. Pallido-muscular coherence was affected by a head tremor and disappeared after IMU regression. Our results show that the Percept PC can record low-frequency oscillations but also reveal spectral contamination due to movement artifacts. IMU regression can identify such artifact contamination and be a suitable tool for its removal. KW - dystonia KW - tremor KW - local field potentials KW - globus pallidus KW - deep brain stimulation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313498 SN - 2306-5354 VL - 10 IS - 4 ER -