title: Assessment of the haptic robot as a new tool for the study of the neural control of reaching.
abstract: 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.
authors.affiliation: Division of Neurology, Institute of Clinical Neurophysiology, University Medical Centre Ljubljana, Zaloska 7, Ljubljana, Slovenia, ris101@gmail.com.
authors.forename: Martin
authors.initials: M
authors.lastname: Rakusa
authors.forename: Ales
authors.initials: A
authors.lastname: Hribar
authors.forename: Blaz
authors.initials: B
authors.lastname: Koritnik
authors.forename: Marko
authors.initials: M
authors.lastname: Munih
authors.forename: Piero Paolo
authors.initials: PP
authors.lastname: Battaglni
authors.forename: Ales
authors.initials: A
authors.lastname: Belic
authors.forename: Janez
authors.initials: J
authors.lastname: Zidar
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D003344:Cortical Synchronization; D004569:Electroencephalography; D005260:Female; D006225:Hand / Q000294:innervation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009068:Movement / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012371:Robotics
chemical_list: D010100:Oxygen