36 CHAPTER 2 Neuroimaging. An eye monitor will be utilized during the MRI scanning to monitor alertness. In addition to the secondary MRI outcome (i.e. the HLJT motor imagery taskbased functional MRI signal), two different neuroimaging markers of cerebral organization will be used: A. Functional (re)organization in rest a. Participants will be asked to lie still, think of nothing in particular and look at a fixation cross while 7min of resting-state functional MRI data are obtained. b. Changes in functional activity and connectivity of several brain areas and cognitive resting-state networks (including the sensorimotor, frontoparietal and executive control networks) will be analyzed primarily with independent component analysis techniques on resting-state functional MRI data. 62 B. Structural (re)organization a. Changes in cerebral grey and white matter will be assessed using structural brain analysis based on anatomical T1-weighted MRI scans. We will perform voxel-based morphometry, a validated and fully automated technique for computational analysis of differences in global and local grey and/or white matter volume. 63 As this part of the study is exploratory, analyses of the resting-state functional MRI data and structural MRI data will not be focused on a priori regions or networks of interests. In addition to the resting-state functional MRI and structural MRI scans, a new first-person motor imagery is employed to further assess motor planning and representations. C. Neuromotor Encoding in Neuromuscular Scapular dyskinesia task (NENS-task) a. This first-person motor imagery task was specifically designed to investigate the impact of central motor planning in the clinical phenomenon of scapular dyskinesia. Participants are asked to imagine making pointing movements with their left or right elbow (novel movement) or finger (trained movements) towards targets shown on a computer screen, and to indicate with a right-foot button press when they have finished imaging the movement (i.e. when they have reached the target with the specified body part). Performance is evaluated by means of response times. Response time is defined as the time from stimulus onset to button press. b. For the NENS task, bipolar EMG of both serratus anterior muscles is used, to monitor muscle activity and exclude the influence of overt movements. The NENS task is performed outside the MRI environment, seated behind a computer screen. Other exploratory outcomes Position and orientation of the scapula: the 3D position and orientation of the scapula will be explored with a new measurement protocol. Anatomical locations for marker placement will be identified through manual palpation by a trained assessor (RL). These anatomical locations correspond to a thoracic reference plane (top and bottom of sternum, spine (vertebrae C7, T8), and three bony landmarks of the scapula (the angulus
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