Parkinson’s disease (PD) is characterized by a progressive impairment of motor skills with deterioration of autonomy in daily living activities. Physiotherapy is regarded as an adjuvant to ...pharmacological and neurosurgical treatment and may provide small and short-lasting clinical benefits in PD patients. However, the development of innovative rehabilitation approaches with greater long-term efficacy is a major unmet need. Motor imagery (MI) and action observation (AO) have been recently proposed as a promising rehabilitation tool. MI is the ability to imagine a movement without actual performance (or muscle activation). The same cortical-subcortical network active during motor execution is engaged in MI. The physiological basis of AO is represented by the activation of the “mirror neuron system.” Both MI and AO are involved in motor learning and can induce improvements of motor performance, possibly mediated by the development of plastic changes in the motor cortex. The review of available evidences indicated that MI ability and AO feasibility are substantially preserved in PD subjects. A few preliminary studies suggested the possibility of using MI and AO as parts of rehabilitation protocols for PD patients.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Walking encompasses a complex interplay of neuromuscular coordination and cognitive processes. Disruptions in gait can impact personal independence and quality of life, especially among the elderly ...and neurodegenerative patients. While traditional biomechanical analyses and neuroimaging techniques have contributed to understanding gait control, they often lack the temporal resolution needed for rapid neural dynamics. This study employs a mobile brain/body imaging (MoBI) platform with high-density electroencephalography (hd-EEG) to explore event-related desynchronization and synchronization (ERD/ERS) during overground walking. Simultaneous to hdEEG, we recorded gait spatiotemporal parameters. Participants were asked to walk under usual walking and dual-task walking conditions. For data analysis, we extracted ERD/ERS in α, β, and γ bands from 17 selected regions of interest encompassing not only the sensorimotor cerebral network but also the cognitive and affective networks. A correlation analysis was performed between gait parameters and ERD/ERS intensities in different networks in the different phases of gait. Results showed that ERD/ERS modulations across gait phases in the α and β bands extended beyond the sensorimotor network, over the cognitive and limbic networks, and were more prominent in all networks during dual tasks with respect to usual walking. Correlation analyses showed that a stronger α ERS in the initial double-support phases correlates with shorter step length, emphasizing the role of attention in motor control. Additionally, β ERD/ERS in affective and cognitive networks during dual-task walking correlated with dual-task gait performance, suggesting compensatory mechanisms in complex tasks. This study advances our understanding of neural dynamics during overground walking, emphasizing the multidimensional nature of gait control involving cognitive and affective networks.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract Valence (positive and negative) and content (embodied vs non-embodied) characteristics of visual stimuli have been shown to influence motor readiness, as tested with response time paradigms. ...Both embodiment and emotional processing are affected in Parkinson’s disease (PD) due to basal ganglia dysfunction. Here we aimed to investigate, using a two-choice response time paradigm, motor readiness when processing embodied (emotional body language EBL and emotional facial expressions FACS) vs non-embodied (emotional scenes IAPS) stimuli with neutral, happy, and fearful content. We enrolled twenty-five patients with early-stage PD and twenty-five age matched healthy participants. Motor response during emotional processing was assessed by measuring response times (RTs) in a home-based, forced two-choice discrimination task where participants were asked to discriminate the emotional stimulus from the neutral one. Rating of valence and arousal was also performed. A clinical and neuropsychological evaluation was performed on PD patients. Results showed that RTs for PD patients were longer for all conditions compared to HC and that RTs were generally longer in both groups for EBL compared to FACS and IAPS, with the sole exception retrieved for PD, where in discriminating fearful stimuli, RTs for EBL were longer compared to FACS but not to IAPS. Furthermore, in PD only, when discriminating fearful respect to neutral stimuli, RTs were shorter when discriminating FACS compared to IAPS. This study shows that PD patients were faster in discriminating fearful embodied stimuli, allowing us to speculate on mechanisms involving an alternative, compensatory, emotional motor pathway for PD patients undergoing fear processing.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Deferiprone was shown to reverse iron deposition in Friedreich's ataxia. This multi-center, unblinded, single-arm pilot study evaluated safety and efficacy of deferiprone for reducing cerebral iron ...accumulation in neurodegeneration with brain iron accumulation. Four patients with genetically-confirmed pantothenate kinase-associated neurodegeneration, and 2 with parkinsonism and focal dystonia, but inconclusive genetic tests, received 15 mg/kg deferiprone bid. Magnetic resonance imaging and neurological examinations were conducted at baseline, six and 12 months. Chelation treatment caused no apparent hematologic or neurological side effects. Magnetic resonance imaging revealed decreased iron accumulation in the globus pallidus of 2 patients (one with pantothenate kinase-associated neurodegeneration). Clinical rating scales and blinded video rating evaluations documented mild-to-moderate motor improvement in 3 patients (2 with pantothenate kinase-associated neurodegeneration). These results underline the safety and tolerability of deferiprone, and suggest that chelating treatment might be effective in improving neurological manifestations associated with iron accumulation. (Clinicaltrials.gov Identifier: NTC00907283).
The pathophysiological mechanisms underlying freezing of gait (FOG) are poorly defined. MRI studies in FOG showed a distinct pattern of cortical atrophy and decreased functional connectivity (FC) ...within motor and cognitive networks. Furthermore, reduced rs-FC within midbrain, frontal, and temporal areas has been also described. This study investigated the patterns of whole-brain FC alterations within midbrain inter-connected regions in PD-FOG patients, and whether these patterns are linked to midbrain structural damage using a multi-modal imaging approach, combing structural and functional imaging techniques.
Thirty three PD patients (16 PD-FOG, 17 PD noFOG), and 21 sex- and age-matched healthy controls (HCs) were prospectively enrolled. All subjects underwent MRI scan at 1.5T, whereas only PD patients underwent clinical and cognitive assessment. Grey matter (GM) integrity was measured using voxel-based morphometry (VBM). VBM findings served as basis to localize midbrain damage, and were further used as a seed region for investigating whole-brain FC alterations using rs-fMRI.
In rs-fMRI, patients with PD and FOG demonstrated significant decrease of midbrain-cortical FC levels in the R PCG, right postcentral, and supramarginal gyri compared to controls and the middle cingulate compared to noFOG group. Based on the regression analysis, MOCA, UPDRS-III total score, and FOG severity scores were associated with FC levels in several frontal, parietal and temporal regions.
The present results suggest that midbrain structural damage as well as decreased FC within the brainstem functional network might contribute to FOG occurrence in PD patients.
Mirror visual feedback (MVF) therapy has been demonstrated to be successful in neurorehabilitation, probably inducing neuroplasticity changes in the primary motor cortex (M1). However, it is not ...known whether MVF training influences the hemispheric balance between the M1s. This topic is of extreme relevance when MVF training is applied to stroke rehabilitation, as the competitive interaction between the two hemispheres induces abnormal interhemispheric inhibition (IHI) that weakens motor function in stroke patients. In the present study, we evaluated, in a group of healthy subjects, the effect of motor training and MVF training on the excitability of the two M1s and the IHI between M1s. The IHI from the ‘active’ M1 to the opposite M1 (where ‘active’ means the M1 contralateral to the moving hand in the motor training and the M1 of the seen hand in the MVF training) increased, after training, in both the experimental conditions. Only after motor training did we observe an increase in the excitability of the active M1. Our findings show that training based on MVF may influence the excitability of the transcallosal pathway and support its use in disorders where abnormal IHI is a potential target, such as stroke, where an imbalance between the affected and unaffected M1s has been documented.
Mirror visual feedback therapy has been demonstrated to be successful in neuro‐rehabilitation likely inducing neuroplasticity changes in the primary motor cortex (M1). However, it is not known whether mirror visual feedback training influences the hemispheric balance between the M1s. In the present study, we evaluated, in a group of healthy subjects, the effect of active motor training (GROUP 1) and mirror visual feedback training (GROUP 2) on the excitability of the two M1s (IO curve slope) and the interhemispheric inhibition (IHI) between M1s. The IHI from the “active” M1 to the opposite (where ‘active’ means the M1 contralateral to the moving hand in the motor training and the M1 of the seen hand in the mirror visual feedback training) increased, after training, in both the experimental conditions. Only after motor training, we observed an increase in the excitability of the ‘active’ M1. Our findings document that a training based on mirror visual feedback may influence the excitability of the transcallosal pathway and support its use in disorders where abnormal IHI is a potential target as stroke, where an unbalance between the affected and unaffected M1 has been documented.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Superficial siderosis (SS) of the central nervous system is a rare and heterogeneous condition due to deposition of hemosiderin on the surface of the brain and spinal cord. The usually ...progressive clinical course is characterized by a combination of hearing loss, cerebellar ataxia, and myelopathy. There is no known treatment for SS, but the iron chelator deferiprone (DFP) has been proposed as a potentially useful treatment.
Methods
We present a long-term (average 3.7 years) evaluation of four cases of SS treated with DFP (15 mg/kg po bid).
Results
Treatment with DFP proved safe and well tolerated. Two out of the four subjects were unchanged while the other two presented a clinical improvement with reduction of postural instability and cerebellar signs. Blinded evaluation of magnetic resonance imaging (performed every 6 months during follow-up) showed a reduction of the abnormal iron deposition for all patients.
Conclusions
This long-term observational study suggests that DFP may be effective in the management of the neurological manifestations associated with iron accumulation in SS.
Clinicaltrials.gov
identifier
NTC00907283
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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