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Current experimental methods for the study of reaching in the MRI environment do not exactly mimic actual reaching, due to constrains in movement which are imposed by the MRI machine itself. We tested a haptic robot (HR) as such a tool. Positive results would also be promising for combined use of fMRI and EEG to study reaching. Twenty right-handed subjects performed reaching tasks with their right hand with and without the HR. Reaction time, movement time (MT), accuracy, event-related potentials (ERPs) and event-related desynchronisation/synchronisation (ERD/ERS) were studied. Reaction times and accuracies did not differ significantly between the two tasks, while the MT was significantly longer in HR reaching (959 vs. 447 ms). We identified two positive and two negative ERP peaks across all leads in both tasks. The latencies of the P1 and N2 peaks were significantly longer in HR reaching, while there were no significant differences in the P3 and N4 latencies. ERD/ERS topographies were similar between tasks and similar to other reaching studies. Main difference was in ERS rebound which was observed only in actual reaching. Probable reason was significantly larger MT. We found that reaching with the HR engages similar neural structures as in actual reaching. Although there are some constrains, its use may be superior to other techniques used for reaching studies in the MRI environment, where freedom of movement is limited. [ABSTRACT FROM AUTHOR]

This paper presents the development and testing of a haptic interface compatible with a functional magnetic resonance imaging (fMRI) environment for neuroscience human motor control studies. A carbon fiber extension enables us to use the widely accepted and available haptic device Phantom 1.5. In the first part of the paper development of the mechanical extension together with its kinematic and dynamic models are presented. The second part is focused on testing of the extended haptic interface. The experiment's results both inside and outside the fMRI environment are presented. Tests outside a scanner have shown that the mechanical extension has no notable effect on a subject performance. Experiments with the scanner have confirmed electromagnetic compatibility of the extended haptic system. At the end it is concluded that the extended haptic device is fully compatible with the fMRI environment, and a virtual environment task that will allow neuroscientists to study a human motor control is proposed. [ABSTRACT FROM AUTHOR]