Ivica Husárová

Predictive motor timing performance dissociates between early diseases of the cerebellum and Parkinson's disease.

There is evidence that both the basal ganglia and the cerebellum play a role in the neural representation of time in a variety of behaviours, but whether one of them is more important is not yet clear. To address this question in the context of predictive motor timing, we tested patients with various movement disorders implicating these two structures in a motor-timing task. Specifically, we investigated four different groups: (1) patients with early Parkinsons disease (PD); (2) patients with sporadic spinocerebellar ataxia (SCA); (3) patients with familial essential tremor (ET); and (4) matched healthy controls. We used a predictive motor-timing task that involved mediated interception of a moving target, and we assessed the effect of movement type (acceleration, deceleration and constant), speed (slow, medium and fast) and angle (0°, 15° and 30°) on performance (hit, early error and late error). The main results showed that PD group and arm ET subgroup did not significantly differ from the control group. SCA and head ET subjects (severe and mild cerebellar damage, respectively) were significantly worse at interception than the other two groups. Our findings support the idea that the basal ganglia play a less significant role in predictive motor timing than the cerebellum. The fact that SCA and ET subjects seemed to have a fundamental problem with predictive motor timing suggests that the cerebellum plays an essential role in integrating incoming visual information with the motor output in a timely manner, and that ET is a heterogeneous entity that deserves increased attention from clinicians.

Functional Imaging of the Cerebellum and Basal Ganglia During Predictive Motor Timing in Early Parkinson's Disease

The basal ganglia and the cerebellum have both emerged as important structures involved in the processing of temporal information.

Essential tremor, the cerebellum, and motor timing: towards integrating them into one complex entity.

Essential tremor (ET) is the most common movement disorder in humans. It is characterized by a postural and kinetic tremor most commonly affecting the forearms and hands. Isolated head tremor has been found in 1–10% of patients, suggesting that ET may be a composite of several phenotypes. The exact pathophysiology of ET is still unknown. ET has been repeatedly shown as a disorder of mild cerebellar degeneration, particularly in postmortem studies. Clinical observations, electrophysiological, volumetric and functional imaging studies all reinforce the fact that the cerebellum is involved in the generation of ET. However, crucial debate exists as to whether ET is a neurodegenerative disease. Data suggesting that it is neurodegenerative include postmortem findings of pathological abnormalities in the brainstem and cerebellum, white matter changes on diffusion tensor imaging, and clinical studies demonstrating an association with cognitive and gait changes. There is also conflicting evidence against ET as a neurodegenerative disease: the improvement of gait abnormalities with ethanol administration, lack of gray matter volume loss on voxel-based morphometry, failure to confirm the prominent presence of Lewy bodies in the locus ceruleus, and other pathological findings. To clarify this issue, future research is needed to describe the mechanism of cellular changes in the ET brain and to understand the order in which they occur. The cerebellum has been shown to be involved in the timing of movement and sensation, acting as an internal timing system that provides the temporal representation of salient events spanning hundreds of milliseconds. It has been reported that cerebellar timing function is altered in patients with ET, showing an increased variability of rhythmic hand movements as well as diminished performance during predictive motor timing task. Based on current knowledge and observations, we argue that ET is essentially linked with cerebellar degeneration, or at least cerebellar dysfunction, together with disturbance of motor timing. We explain the context of our current understanding on this topic, highlighting possible clinical consequences for patients suffering from ET and future research directions.

Similar Circuits but Different Connectivity Patterns Between The Cerebellum, Basal Ganglia, and Supplementary Motor Area In Early Parkinson's Disease Patients and Controls During Predictive Motor Timing

The cerebellum, basal ganglia (BG), and other cortical regions, such as supplementary motor area (SMA) have emerged as important structures dealing with various aspects of timing, yet the modulation of functional connectivity between them during motor timing tasks remains unexplored.

44. The cerebellum, basal ganglia and motor timing in movement disorders. Behavioral and fMRI study

Introduction Published studies demonstrated that the cerebellum and basal ganglia participate in various motor and non-motor task related to prediction. In a series of behavioural and functional imaging studies we studied different populations of patients with movements disorders to clarify the role of the cerebellum and basal ganglia with respect to the motor timing. Methods Specifically, we investigated four different groups: (i) patients with early Parkinson’s disease (PD); (ii) patients with sporadic spinocerebellar ataxia (SCA); (iii) patients with essential tremor (ET); (IV) patients with focal dystonia – cervical dystonia (CD) and (v) matched healthy controls. We used a predictive motor timing task that involved mediated interception of a moving target, and we assessed the effect of movement type (acceleration, deceleration, constant), speed (slow, medium, fast), and angle (0°, 15°, 30°) on performance (hit, early error, late error). Using functional magnetic resonance imaging (fMRI) we evaluated the effect of hits, early errors, late errors – and their contrasts. Results Behavioral: The main results showed that the PD group did not significantly differ from the control group. However, the SCA, ET and CD subjects (severe and mild cerebellar damage, respectively) were significantly worse at interception than the other two groups. We found that the PD patients failed to postpone their action until the right moment and to adapt from one trial to the next more often than the controls. Imaging The lobule VI of the right cerebellum was more activated in the healthy controls relative to the PD patients during successful trials. Also, successful trial-by-trial adjustments were associated with more pronounced activation in the right putamen and lobule VI for the healthy controls relative to the PD patients. PD subjects and healthy controls used identical functional circuits to maintain the successful outcome in predictive motor timing behavior, however the strength of effective connectivity differed between these two groups. Conclusions The cerebellum plays an essential role in integrating incoming visual information with motor output when making predictions about upcoming actions. Both the cerebellum and the basal ganglia are necessary for the predictive motor timing in general, with the cerebellum being associated with the postponement of the action until the right moment, and with both the cerebellum and the basal ganglia needed for successful adaptation in the task from one trial to the next. Future studies of the exact roles of subcortical structures in movement disorders is the challenge for the researchers. This work was supported by the project “CEITEC – Central European Institute of Technology” (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund and by a research project of the Czech Ministry of Health Foundation (2010–2015) NT/13437.

Generalized myoclonus as a prominent symptom in a patient with FTLD-TDP

We report on a patient who developed generalized asymmetric myoclonus associated with frontotemporal lobar degeneration with TDP-43 positive inclusions (FTLD-TDP).

Correspondence on ‘‘Outcome Measures Used in Studies of Botulinum Toxin in Childhood Cerebral Palsy: A Systematic Review’’

Used outcome measures and scales in the treatment of spasticity in cerebral palsy with botulinum toxin: systematic overview of the current literature

24. Basal ganglia and cerebellum in the motor timing prediction task: Effective connectivity

transform was performed and potential of its features was tested. The dataset consisted of EEG channels from polysomnographic recordings of 12 healthy term newborns. From each recording artifact-free parts corresponding to active and quiet sleep were selected. As processing of this type of signal is a complex multilevel procedure, we focused our attention on feature extraction. After the application of constant segmentation each segment was represented by its features, derived after the application of discrete WT. Set of extracted features comprised statistical parameters as well as total and relative sub-band energies. We explored how these features change for different behavioral states, and how their values changed with the position of electrodes. Also, as parameters of WT various types of mother wavelets were tested. For final classification the same classifier was used through the study in order to obtain comparable results. As feature extraction is important for automatic classification, obtained results concerning WT parameters and appropriate features may provide a reference for developing or enhancing algorithms in this field of EEG application. Acknowledgement: This research was supported by Grant Nos. 1ET101210512 and MSM6840770012.

MO19 Functional imaging of the cerebellum and subcortical structures in early Parkinson's disease in timing prediction task: fMRI study

MO16 Combining EEG and fMRI to investigate the cortical oscillatory activities during finger movement Emanuela Formaggio 1, Mirko Avesani 1, Silvia Francesca Storti 1 , Michele Acler 1, Franco Milanese 1 , Anna Gasparini 2, Roberto Cerini 2, Roberto Pozzi Mucelli 2 , Antonio Fiaschi 1, Paolo Manganotti 1 1Section of Neurological Rehabilitation, Department of Neurological and Visual Sciences, “Gianbattista Rossi” Hospital, University of Verona, Verona, Italy; 2Department of Morphologic and Biomedical Sciences, “Gianbattista Rossi” Hospital, University of Verona, Verona, Italy; 3Section of Neurological Rehabilitation, Department of Neurological and Visual Sciences, “Gianbattista Rossi” Hospital, University of Verona, Verona, Italy.-IRCCS “San Camillo” Hospital-Venice-Italy