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Objective. Impaired trunk stability is frequent in spinal cord injury (SCI), but there is a lack of quantitative measures for assessing trunk function. Our objectives were to: (a) evaluate trunk muscle activity and movement patterns during a reaching task in SCI patients, (b) compare the impact of cervical (cSCI) and thoracic (tSCI) injuries in trunk function, and (c) investigate the effects of a startling acoustic stimulus (SAS) in these patients. Approach. Electromyographic (EMG) and smartphone accelerometer data were recorded from 15 cSCI patients, nine tSCI patients, and 24 healthy controls, during a reaching task requiring trunk tilting. We calculated the response time (RespT) until pressing a target button, EMG onset latencies and amplitudes, and trunk tilt, lateral deviation, and other movement features from accelerometry. Statistical analysis was applied to analyze the effects of group (cSCI, tSCI, control) and condition (SAS, non-SAS) in each outcome measure. Main results. SCI patients, especially those with cSCI, presented significantly longer RespT and EMG onset latencies than controls. Moreover, in SCI patients, forward trunk tilt was accompanied by significant lateral deviation. RespT and EMG latencies were remarkably shortened by the SAS (the so-called StartReact effect) in tSCI patients and controls, but not in cSCI patients, who also showed higher variability. Significance. The combination of EMG and smartphone accelerometer data can provide quantitative measures for the assessment of trunk function in SCI. Our results show deficits in postural control and compensatory strategies employed by SCI patients, including delayed responses and higher lateral deviations, possibly to improve sitting balance. This is the first study investigating the StartReact responses in trunk muscles in SCI patients and shows that the SAS significantly accelerates RespT in tSCI, but not in cSCI, suggesting an increased cortical control exerted by these patients., Peer Reviewed, Postprint (published version)

Objective. Impaired trunk stability is frequent in spinal cord injury (SCI), but there is a lack of quantitative measures for assessing trunk function. Our objectives were to: (a) evaluate trunk muscle activity and movement patterns during a reaching task in SCI patients, (b) compare the impact of cervical (cSCI) and thoracic (tSCI) injuries in trunk function, and (c) investigate the effects of a startling acoustic stimulus (SAS) in these patients. Approach. Electromyographic (EMG) and smartphone accelerometer data were recorded from 15 cSCI patients, nine tSCI patients, and 24 healthy controls, during a reaching task requiring trunk tilting. We calculated the response time (RespT) until pressing a target button, EMG onset latencies and amplitudes, and trunk tilt, lateral deviation, and other movement features from accelerometry. Statistical analysis was applied to analyze the effects of group (cSCI, tSCI, control) and condition (SAS, non-SAS) in each outcome measure. Main results. SCI patients, especially those with cSCI, presented significantly longer RespT and EMG onset latencies than controls. Moreover, in SCI patients, forward trunk tilt was accompanied by significant lateral deviation. RespT and EMG latencies were remarkably shortened by the SAS (the so-called StartReact effect) in tSCI patients and controls, but not in cSCI patients, who also showed higher variability. Significance. The combination of EMG and smartphone accelerometer data can provide quantitative measures for the assessment of trunk function in SCI. Our results show deficits in postural control and compensatory strategies employed by SCI patients, including delayed responses and higher lateral deviations, possibly to improve sitting balance. This is the first study investigating the StartReact responses in trunk muscles in SCI patients and shows that the SAS significantly accelerates RespT in tSCI, but not in cSCI, suggesting an increased cortical control exerted by these patients., Peer Reviewed, Postprint (published version)

Trunk stability is essential to maintain upright posture and support functional movements. In this study, we aimed to characterize the muscle activity and movement patterns of trunk flexion during an arm reaching task in sitting healthy subjects and investigate whether trunk stability is affected by a startling acoustic stimulus (SAS). For these purposes, we calculated the electromyographic (EMG) onset latencies and amplitude parameters in 8 trunk, neck, and shoulder muscles, and the tilt angle and movement features from smartphone accelerometer signals recorded during trunk bending in 33 healthy volunteers. Two-way repeated measures ANOVAs were applied to examine the effects of SAS and target distance (15 cm vs 30 cm). We found that SAS markedly reduced the response time and EMG onset latencies of all muscles, without changing neither movement duration nor muscle recruitment pattern. Longer durations, higher tilt angles, and higher EMG amplitudes were observed at 30 cm compared to 15 cm. The accelerometer signals had a higher frequency content in SAS trials, suggesting reduced movement control. The proposed measures have helped to establish the trunk flexion pattern in arm reaching in healthy subjects, which could be useful for future objective assessment of trunk stability in patients with neurological affections., Peer Reviewed, Postprint (published version)

Persistent neuronal spiking has long been considered the mechanism underlying working memory, but recent proposals argue for alternative 'activity-silent' substrates. Using monkey and human electrophysiology data, we show here that attractor dynamics that control neural spiking during mnemonic periods interact with activity-silent mechanisms in the prefrontal cortex (PFC). This interaction allows memory reactivations, which enhance serial biases in spatial working memory. Stimulus information was not decodable between trials, but remained present in activity-silent traces inferred from spiking synchrony in the PFC. Just before the new stimulus, this latent trace was reignited into activity that recapitulated the previous stimulus representation. Importantly, the reactivation strength correlated with the strength of serial biases in both monkeys and humans, as predicted by a computational model that integrates activity-based and activity-silent mechanisms. Finally, single-pulse transcranial magnetic stimulation applied to the human PFC between successive trials enhanced serial biases, thus demonstrating the causal role of prefrontal reactivations in determining working-memory behavior.

Spinal plasticity is thought to contribute to sensorimotor recovery of limb function in several neurological disorders and can be experimentally induced in animals and humans using different stimulation protocols. In healthy individuals, electrical continuous Theta Burst Stimulation (TBS) of the median nerve has been shown to change spinal motoneuron excitability in the cervical spinal cord as indexed by a change in mean H-reflex amplitude in the flexor carpi radialis muscle. It is unknown whether continuous TBS of a peripheral nerve can also shift motoneuron excitability in the lower limb. In 26 healthy subjects, we examined the effects of electrical TBS given to the tibial nerve in the popliteal fossa on the excitability of lumbar spinal motoneurons as measured by H-reflex amplitude of the soleus muscle evoked by tibial nerve stimulation. Continuous TBS was given at 110% of H-reflex threshold intensity and compared to non-patterned regular electrical stimulation at 15 Hz. To disclose any pain-induced effects, we also tested the effects of TBS at individual sensory threshold. Moreover, in a subgroup of subjects we evaluated paired-pulse inhibition of H-reflex. Continuous TBS at 110% of H-reflex threshold intensity induced a short-term reduction of H-reflex amplitude. The other stimulation conditions produced no after effects. Paired-pulse H-reflex inhibition was not modulated by continuous TBS or non-patterned repetitive stimulation at 15 Hz. An effect of pain on the results obtained was discarded, since non-patterned 15 Hz stimulation at 110% HT led to pain scores similar to those induced by EcTBS at 110% HT, but was not able to induce any modulation of the H reflex amplitude. Together, the results provide first time evidence that peripheral continuous TBS induces a short-lasting change in the excitability of spinal motoneurons in lower limb circuitries. Future studies need to investigate how the TBS protocol can be optimized to produce a larger and longer effe

Spinal plasticity is thought to contribute to sensorimotor recovery of limb function in several neurological disorders and can be experimentally induced in animals and humans using different stimulation protocols. In healthy individuals, electrical continuous Theta Burst Stimulation (TBS) of the median nerve has been shown to change spinal motoneuron excitability in the cervical spinal cord as indexed by a change in mean H-reflex amplitude in the flexor carpi radialis muscle. It is unknown whether continuous TBS of a peripheral nerve can also shift motoneuron excitability in the lower limb. In 26 healthy subjects, we examined the effects of electrical TBS given to the tibial nerve in the popliteal fossa on the excitability of lumbar spinal motoneurons as measured by H-reflex amplitude of the soleus muscle evoked by tibial nerve stimulation. Continuous TBS was given at 110% of H-reflex threshold intensity and compared to non-patterned regular electrical stimulation at 15 Hz. To disclose any pain-induced effects, we also tested the effects of TBS at individual sensory threshold. Moreover, in a subgroup of subjects we evaluated paired-pulse inhibition of H-reflex. Continuous TBS at 110% of H-reflex threshold intensity induced a short-term reduction of H-reflex amplitude. The other stimulation conditions produced no after effects. Paired-pulse H-reflex inhibition was not modulated by continuous TBS or non-patterned repetitive stimulation at 15 Hz. An effect of pain on the results obtained was discarded, since non-patterned 15 Hz stimulation at 110% HT led to pain scores similar to those induced by EcTBS at 110% HT, but was not able to induce any modulation of the H reflex amplitude. Together, the results provide first time evidence that peripheral continuous TBS induces a short-lasting change in the excitability of spinal motoneurons in lower limb circuitries. Future studies need to investigate how the TBS protocol can be optimized to produce a larger and longer effe

Background: The differential diagnosis between patients with essential tremor (ET) and those with Parkinson’s disease (PD) whose main manifestation is tremor may be difficult unless using complex neuroimaging techniques such as 123I-FP-CIT SPECT. We considered that using smartphone’s accelerometer to stablish a diagnostic test based on time-frequency differences between PD an ET could support the clinical diagnosis. Methods: The study was carried out in 17 patients with PD, 16 patients with ET, 12 healthy volunteers and 7 patients with tremor of undecided diagnosis (TUD), who were re-evaluated one year after the first visit to reach the definite diagnosis. The smartphone was placed over the hand dorsum to record epochs of 30 s at rest and 30 s during arm stretching. We generated frequency power spectra and calculated receiver operating characteristics curves (ROC) curves of total spectral power, to establish a threshold to separate subjects with and without tremor. In patients with PD and ET, we found that the ROC curve of relative energy was the feature discriminating better between the two groups. This threshold was then used to classify the TUD patients. Results: We could correctly classify 49 out of 52 subjects in the category with/without tremor (97.96% sensitivity and 83.3% specificity) and 27 out of 32 patients in the category PD/ET (84.38% discrimination accuracy). Among TUD patients, 2 of 2 PD and 2 of 4 ET were correctly classified, and one patient having PD plus ET was classified as PD. Conclusions: Based on the analysis of smartphone accelerometer recordings, we found several kinematic features in the analysis of tremor that distinguished first between healthy subjects and patients and, ultimately, between PD and ET patients. The proposed method can give immediate results for the clinician to gain valuable information for the diagnosis of tremor. This can be useful in environments where more sophisticated diagnostic techniques are unavailable., Peer Reviewed, Postprint (published version)

[Abstract] Understanding the origin of muscle fatigue is essential for optimizing neuro-rehabilitation treatments. Fatigue is tasks dependent and its neural substrates have been deeply addressed for isometric contractions. However, we recently showed differences in the silent periods generated at cortical or spinal levels after brief maximal rate finger tapping or isometric force tasks, advocating for a cortical but not spinal origin of fatigue for repetitive movements. Here we extend our previous findings by exploring another spinal cord circuits, as well as analyzing the modification of the compound muscle action potential. We use electric cervi- comedullary stimulation (n = 7) and the recording of the compound muscle action potential, always at the time of fatigue. Once more our results suggest a different place of fatigue onset for each type of task. Fatigue evoked by maximal rate finger tapping does not have its origin at spinal cord level.

[Abstract] Compared to isometric activities, the neural basis of fatigue induced by repetitive tasks has been scarcely studied. Recently, we showed that during short-lasting repetitive tasks at the maximal possible rate (finger tapping for 10 and 30 s), tapping rate and maximal voluntary contraction (MVC) force decrease at the end of finger tapping. We also observed larger silent periods (SP) induced by transcranial magnetic stimulation during MVC post finger tapping. However, if SP were induced by cervicomedullary stimulation (CMS) they remained unchanged. This suggested a supraspinal origin of fatigue for repetitive tasks. Nevertheless, CMS SP only partially explore spinal excitability; therefore, to evaluate a spinal origin of fatigue it is essential to know the features of the CMS-evoked potentials (CMEP). Herein, we evaluated (n = 15) the amplitude of the CMEP during MVC executed immediately (no gap) after a short-lasting finger tapping task; we also evaluated the compound muscle action potential (CMAP) so that the amplitude of the CMEP was expressed as a function of the CMAP amplitude. Indices of fatigue obtained during finger tapping were compared with those obtained during short-lasting maximal isometric tasks. While indices of excitability increased initially in both tasks, they decreased with the isometric task only when the task was prolonged to 30 s. We suggest that the inability to maintain increased levels of spinal excitability during task execution is a neurophysiological mark of fatigue. Our results suggest that the origin of fatigue induced by brief and fast repetitive tasks is not spinal.

[Abstract] The neural substrates of fatigue induced by muscular activity have been addressed in depth in relation to isometric tasks. For these activities, when fatigue develops, it has been noted that the duration of the silent periods (SPs) increases in response to both transcranial magnetic stimulation (TMS) of primary motor cortex or electric cervicomedullary stimulation (CMS). However, fatigue is known to be task-dependent and the mechanisms giving rise to a decrease in motor performance during brief, fast repetitive tasks have been less studied. We hypothesized that fatigue induced by repetitive fast finger tapping may have physiological mechanisms different from those accounting for fatigue during an isometric contraction, even in cases of matched effort durations. In these tasks, we examined the contribution of spinal and supraspinal motor circuits to the production of fatigue. The tapping rate and maximal voluntary contractions (MVC), and TMS- and CMS-evoked SPs were obtained at the time of fatigue, and while subjects maintained maximal muscle activation after fast finger-tapping (or isometric activity) of different durations (10 or 30 s). Results showed different mechanisms of fatigue triggered by isometric contraction and repetitive movements, even of short duration. Short-lasting repetitive movements induce fatigue within intracortical inhibitory circuits. They increased TMS-SPs, but not CMS-SPs. On the other hand, isometric contraction had a clear impact on spinal circuits. The consideration of these differences might help to optimize the study of fatigue in physiological conditions and neurological disorders.

Las lesiones medulares presentan, como una de las consecuencias principales, una alteración o pérdida de la capacidad de marcha. Basado en modelos animales, a finales de los años 80 se desarrolló el Entrenamiento de la Marcha Asistida con Soporte Parcial del Peso Corporal (EMA-SPPC) utilizando una cinta sin fin y la suspensión parcial del peso corporal mediante un arnés. El desarrollo de tecnología robótica para el EMA-SPPC ha llevado a la introducción de sistemas como el Lokomat® y el Gait Trainer GT I® en los centros de neurorehabilitación. Planteamos un estudio longitudinal en pacientes con una lesión medular utilizando estos dos sistemas (Lokomat® o Gait Trainer GT I®) con una frecuencia y duración del entrenamiento determinadas. La respuesta al entrenamiento la valoramos utilizando escalas clínicas y funcionales ya establecidas que nos permiten objetivar las ganancias obtenidas. Los resultados apoyan el uso preferente de estos sistemas en pacientes con una lesión motora incompleta y que los mayores beneficios se encuentran cuando se inicia el entrenamiento en las fases tempranas, dentro de los 6 primeros meses tras la lesión. Como otra herramienta de valoración de resultados utilizamos también técnicas neurofisiológicas. Es conocida la importancia de la modulación de los reflejos para obtener un control motor adecuado. En concreto examinamos la modulación del reflejo H por estimulación magnética transcraneal (EMT) y su evolución tras el entrenamiento de la marcha. De esta forma encontramos que los pacientes con una lesión medular incompleta motora tienen alteraciones en el control de los reflejos espinales segmentarios, cuyo correlato neurofisiológico se encuentra en una disminución de la facilitación del reflejo H inducida por EMT (en la fase de 20 ms.). La facilitación temprana (20 ms) del reflejo H por EMT aumenta en mayor medida tras la rehabilitación en aquellos pacientes que empezaron su entrenamiento con 3 meses desde su lesión. Existe una correlación po, Spinal cord injuries (SCI) have as one of the main consequences, the alteration or loss of the ambulation capacity. Based on animal models, in the late 1980s, body weight–supported treadmill training (BWSTT) was developed for gait rehabilitation using a treadmill, body weight support, and manual assistance. The development of robotic technology for the BWSTT, has come to the introduction of new systems like the Lokomat® and the Gait Trainer GT I® in the neurorehabilitation centers. We conducted a longitudinal study in subjects with a spinal cord injury using these two systems (Lokomat® or Gait Trainer GT I®) with the same frequency and duration of training. The response to training was assessed using accepted clinical impairment and functional scales, allowing us to assess the improvement obtained. The results support the preferred use of these systems in patients with an incomplete motor lesion, and that the most benefits are obtained if the training is started in the initial phases, especially in the first 6 months post injury. As another tool for evaluation of outcomes we also use neurophysiological techniques. It is well known, that the modulation of reflexes is an important aspect of motor control. In particularly we studied the H reflex modulation by transcranial magnetic stimulation (TMS) and its change after gait training. We found that the subjects with a motor incomplete SCI have a deficit in the appropriate control of the spinal reflexes, with a neurophysiologic correlation of a reduced H reflex facilitation by TMS (phase of 20 ms). The H reflex modulation by TMS at the early phase (20 ms) improves after gait training on those subjects who stated the training in the first 3 months after injury. There is a good correlation between the increase of H reflex facilitation and the improvement in functional aspects (gait scale WISCI II) after training in the group with less than 3 months after injury. The H reflex modulation by TMS may be another neurophysiologi

Las lesiones medulares presentan, como una de las consecuencias principales, una alteración o pérdida de la capacidad de marcha. Basado en modelos animales, a finales de los años 80 se desarrolló el Entrenamiento de la Marcha Asistida con Soporte Parcial del Peso Corporal (EMA-SPPC) utilizando una cinta sin fin y la suspensión parcial del peso corporal mediante un arnés. El desarrollo de tecnología robótica para el EMA-SPPC ha llevado a la introducción de sistemas como el Lokomat® y el Gait Trainer GT I® en los centros de neurorehabilitación. Planteamos un estudio longitudinal en pacientes con una lesión medular utilizando estos dos sistemas (Lokomat® o Gait Trainer GT I®) con una frecuencia y duración del entrenamiento determinadas. La respuesta al entrenamiento la valoramos utilizando escalas clínicas y funcionales ya establecidas que nos permiten objetivar las ganancias obtenidas. Los resultados apoyan el uso preferente de estos sistemas en pacientes con una lesión motora incompleta y que los mayores beneficios se encuentran cuando se inicia el entrenamiento en las fases tempranas, dentro de los 6 primeros meses tras la lesión. Como otra herramienta de valoración de resultados utilizamos también técnicas neurofisiológicas. Es conocida la importancia de la modulación de los reflejos para obtener un control motor adecuado. En concreto examinamos la modulación del reflejo H por estimulación magnética transcraneal (EMT) y su evolución tras el entrenamiento de la marcha. De esta forma encontramos que los pacientes con una lesión medular incompleta motora tienen alteraciones en el control de los reflejos espinales segmentarios, cuyo correlato neurofisiológico se encuentra en una disminución de la facilitación del reflejo H inducida por EMT (en la fase de 20 ms.). La facilitación temprana (20 ms) del reflejo H por EMT aumenta en mayor medida tras la rehabilitación en aquellos pacientes que empezaron su entrenamiento con < 3 meses desde su lesión. Existe una correlación, Spinal cord injuries (SCI) have as one of the main consequences, the alteration or loss of the ambulation capacity. Based on animal models, in the late 1980s, body weight–supported treadmill training (BWSTT) was developed for gait rehabilitation using a treadmill, body weight support, and manual assistance. The development of robotic technology for the BWSTT, has come to the introduction of new systems like the Lokomat® and the Gait Trainer GT I® in the neurorehabilitation centers. We conducted a longitudinal study in subjects with a spinal cord injury using these two systems (Lokomat® or Gait Trainer GT I®) with the same frequency and duration of training. The response to training was assessed using accepted clinical impairment and functional scales, allowing us to assess the improvement obtained. The results support the preferred use of these systems in patients with an incomplete motor lesion, and that the most benefits are obtained if the training is started in the initial phases, especially in the first 6 months post injury. As another tool for evaluation of outcomes we also use neurophysiological techniques. It is well known, that the modulation of reflexes is an important aspect of motor control. In particularly we studied the H reflex modulation by transcranial magnetic stimulation (TMS) and its change after gait training. We found that the subjects with a motor incomplete SCI have a deficit in the appropriate control of the spinal reflexes, with a neurophysiologic correlation of a reduced H reflex facilitation by TMS (phase of 20 ms). The H reflex modulation by TMS at the early phase (20 ms) improves after gait training on those subjects who stated the training in the first 3 months after injury. There is a good correlation between the increase of H reflex facilitation and the improvement in functional aspects (gait scale WISCI II) after training in the group with less than 3 months after injury. The H reflex modulation by TMS may be another neurophysiologi

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Biosignal Interpretation: Advanced Methods for Neural Signals and Images“. Objectives: An efficient way to investigate the neural basis of nociceptive responses is the analysis of the event-related brain potentials (ERPs). The main objective of this work was to study how adaptation and fatigue affect the ERPs to stimuli of different modalities, by characterizing the responses to infrequent and frequent stimulation in different recording periods. Methods: In this work, series of averaged EEG epochs recorded after thermal, electrical and auditory stimulation were analyzed with time-frequency representation and non-linear measures as spectral entropy and auto-mutual information function. The study was performed by considering the traditional EEG frequency bands. Results: The defined measures presented a statistical significance p-value < 0.01 and accuracy higher than 60% by differentiating windows of response to infrequent (I) and frequent (F) stimuli between the start and end of the EEG recording. Conclusions: These measures permitted to observe some aspects of the subject’s adaptation and the nociceptive response, Peer Reviewed, Postprint (published version)

[Abstract] Startle stimuli lead to shorter reaction times in control subjects and Parkinson's disease (PD) patients. However, non-startle stimuli also enhance movement initiation in PD. We wanted to examine whether a startle-triggered movement would retain similar kinematic and EMG-related characteristics compared to one induced by a non-startle external cue in PD patients. In this study we investigated the electromyography pattern and the reaction time during a wrist flexion movement in response to three different stimuli: a visual imperative stimulus; visual stimulus simultaneous with a non-startle auditory stimulus and with a startle auditory stimulus. Ten PD patients and ten aged matched controls participated in this study. The reaction times were faster for startle and non-startle stimuli in comparison with the visual imperative stimulus, in both patients and control subjects. The startle cue induced a faster reaction than the non-startle cue. The electromyography pattern remained unchanged across the conditions. The results suggest that the startle reaction effect for upper limb movements are unimpaired in PD patients and has different characteristics than the effect of non-startle stimuli.

[Abstract] Background. Auditory external cues enhance step initiation in Parkinson's disease (PD) patients. We wanted to explore whether a startle reaction has a comparable effect on step initiation in PD. Methods. Thirteen PD patients and 13 aged-matched controls participated in this study. Electromyography pattern and onset toe-off time during a step initiation task were recorded in response to three different stimuli: a visual imperative stimulus; visual stimulus simultaneous with a nonstartle auditory stimulus and with a startle auditory stimulus. Results. In all subjects, onset of tibialis anterior was faster in the startle auditory condition, compared with the nonstartle auditory condition. However, in the patient group, there was no difference in onset of soleus and toe-off between the startle and nonstartle conditions. Conclusions. Startle reaction in PD patients demonstrates a disordered coupling between the anticipatory postural adjustments that initiate the weight shift and the movement to initiate toe-off during step initiation.

OBJECTIVES: to provide a revised version of earlier guidelines published in 2006. BACKGROUND: primary dystonias are chronic and often disabling conditions with a widespread spectrum mainly in young people. DIAGNOSIS: primary dystonias are classified as pure dystonia, dystonia plus or paroxysmal dystonia syndromes. Assessment should be performed using a validated rating scale for dystonia. Genetic testing may be performed after establishing the clinical diagnosis. DYT1 testing is recommended for patients with primary dystonia with limb onset before age 30, and in those with an affected relative with early-onset dystonia. DYT6 testing is recommended in early-onset or familial cases with cranio-cervical dystonia or after exclusion of DYT1. Individuals with early-onset myoclonus should be tested for mutations in the DYT11 gene. If direct sequencing of the DYT11 gene is negative, additional gene dosage is required to improve the proportion of mutations detected. A levodopa trial is warranted in every patient with early-onset primary dystonia without an alternative diagnosis. In patients with idiopathic dystonia, neurophysiological tests can help with describing the pathophysiological mechanisms underlying the disorder. TREATMENT: botulinum toxin (BoNT) type A is the first-line treatment for primary cranial (excluding oromandibular) or cervical dystonia; it is also effective on writing dystonia. BoNT/B is not inferior to BoNT/A in cervical dystonia. Pallidal deep brain stimulation (DBS) is considered a good option, particularly for primary generalized or cervical dystonia, after medication or BoNT have failed. DBS is less effective in secondary dystonia. This treatment requires a specialized expertise and a multidisciplinary team.

Peer Reviewed, Postprint (published version)

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