In analogy to observations in voluntary hand movements (Berends et al., 2013, Macuga and Frey, 2012 and Nedelko et al., 2012) we expected the activity to be greater during AO + MI than during AO or MI in both the static and dynamic balance task. In summary, the overall goal of this study was to identify differences in the pattern of neural activity evoked by MI, AO and AO + MI of differently demanding balance tasks that can be used to develop recommendations for the non-physical training of immobilized patients. Sixteen healthy participants (6 females) aged between 20 and 37 years (mean ± SD = 27 ± 4.81) free from neurological and orthopedic disorders
participated in this this website study. They had normal or corrected-to-normal vision. All participants were briefed on the experiments and gave written informed consent to the experimental procedure before testing. The study was approved by the local ethics committee and was in accordance with the Declaration of Helsinki. Participants were familiarized with the experimental conditions before scanning started: they watched a video showing the procedure and the various different tasks. After this familiarization phase participants entered the scanner for data acquisition. In the scanner, a video provided written and auditory information
about which of the three conditions and which click here of the two tasks was about to
be presented: The conditions (a) MI during AO (AO + MI), (b) MI, or (c) AO were tested in this order in separate runs with 3 min break in-between. In a random order, two videos showing two different motor tasks were displayed: (i) dynamic standing balance (medio-lateral perturbation on a laterally tilting surface) and (ii) static standing balance. The perturbation video showed a subject counteracting a medio-lateral perturbation in order to regain his balance. The standing video displayed a character in normal PtdIns(3,4)P2 upright bipedal stance, thus hardly moving at all (see Fig. 1). Both videos were repeated every 2 sec for 10 times. Auditory and written instruction before each video provided information about what motor task was about to follow. Each experimental run was composed of 8 blocs (four dynamic and four static trials) and lasted 6 min. Each bloc was composed of a video which lasted 20 sec followed by a 21-sec rest period where a white cross on a black screen was displayed. On the video the start of a new trial was indicated every 2 sec by a sound (for both dynamic and static task). The order of presentation of the static and dynamic balance tasks was fully randomized within an experimental run. The MRI session lasted about 30 min.