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Introduction: An increased knowledge of how the brain control finger movements give us keys to understand the recovery of motor function after a brain injury. This knowledge is crucial for the development of reliable and valid assessment methods in the clinical evaluation of hand function.

Research question: How are individual finger movements represented in the brain? Investigating the associations between kinematics and brain activity responses in healthy individuals.

Methods: Keeping the others still. Finger movements were performed lying in the MR scanner in order to register brain activity response during the task. Optoelectronic cameras simultaneously monitored the positions of reflective markers affixed to each finger. The marker position data were used to calculate each finger's movement frequency (MF),  movement independence (“Individuation Index”, II), stationary ability (Stationarity Index, SI)[1][1]. fMRI data was analyzed by contrasting the finger movements against its active rest.

Results: Preliminary analyses showed that (1) the finger movements primarily activate sensorimotor areas in the contralateral hemisphere (Fig. 1A), (2) that use of kinematic parameters in the fMRI analyses improved spatial specificity and (3) II engage a number of cortical areas, while MF engage fewer areas (Fig. 1B–D). Further analyses will further explore activations maps for each individual finger.

Discussion: The inclusion of movement parameters in the fMRI analyses improves the specificity in the derived activation map, increasing the interpretability of the neural correlates of movement control. This advancement carries the promise for the development of better assessment methods of the recovery of function post-stroke with usability in rehabilitation practices.