Tomáš Gescheidt

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.

Functional anatomy of outcome evaluation during Iowa Gambling Task performance in patients with Parkinson’s disease: an fMRI study

The aim of this study was to investigate the functional anatomy of decision-making during the Iowa Gambling Task in patients with Parkinson’s disease. We used event-related functional magnetic resonance imaging (fMRI) during a computerized version of IGT to compare 18 PD patients on dopaminergic medication in the ON state and 18 healthy control subjects. Our analyses focused on outcome evaluation following card selection, because we expected this aspect of decision-making to be impaired in PD patients. The PD patients exhibited lower activation of the left putamen than the control group as a reaction to penalty. Using psychophysiological interaction analysis, we identified decreased functional connectivity between the right globus pallidus internus and the left anterior cingulate gyrus in the PD group. In contrast, increased connectivity between these structures was observed after penalty in the control group. Our results suggest altered functioning of the basal ganglia and their connections with the cortical structures involved in the limbic loop (e.g., the limbic fronto-striatal circuit of the basal ganglia) during decision-making in PD patients. Differences in the response to loss could be associated with insufficient negative reinforcement after a loss in PD patients in the ON state in comparison to a healthy population.

17. Functional anatomy of outcome evaluation during Iowa Gambling Task performance in patients with Parkinson’s disease: An fMRI study

Introduction The aim of this study was to investigate the functional anatomy of decision-making during the Iowa Gambling Task in patients with Parkinson’s disease (PD). Method We used event-related functional magnetic resonance imaging (fMRI) during a computerized version of IGT to compare 18 PD patients on dopaminergic medication in the ON state and 18 healthy control subjects. Our analyses focused on outcome evaluation following card selection, because we expected this aspect of decision making to be impaired in PD patients. Results The PD patients exhibited lower activation of the left putamen than the control group as a reaction to penalty. Using psychophysiological interaction analysis, we identified decreased functional connectivity between the right globus pallidus internus and the left anterior cingulate gyrus in the PD group. In contrast, increased connectivity between these structures was observed after penalty in the control group. Conclusions Our results suggest altered functioning of the basal ganglia and their connections with the cortical structures involved in the limbic loop (e.g. the limbic fronto-striatal circuit of the basal ganglia) during decision making in PD patients. Differences in the response to loss could be associated with insufficient negative reinforcement following a loss in PD patients in the ON state in comparison to a healthy population. 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. The participation of T.U. was supported by a research project of the Czech Science Foundation, No. P407/12/2432. The participation of J.V. was supported by the European Regional Development Fund Project FNUSA-ICRC (No. CZ.1.05/1.1.00/02.0123).

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