Functional Imaging of Human Spinal Cord – FIHSC

Multiparametric imaging of the human spinal cord for a quantitative evaluation of spinal structures to assess the level of affection at anatomical level
Indirect electrophysiology based on the analysis of the electromyographic (EMG in the muscle) or electroencephalographic signals (EEG, the brain) and their modifications after stimulation of peripheral nerve trunks and / or cerebral cortex

In ALS patients, MRI revealed an anatomical affection of the sensorimotor pathways and electrophysiology, a functional disruption of sensorimotor networks.
We observed that the tDCS modifies the activity of spinal networks in healthy subjects and began the study in hemiplegic patients.

We will continue to include patients to get enough data for valid comparisons. We will test if there is a correlation between anatomical data (MRI) and fucntionnal data (electrophysiology).

in running

Research on human spinal cord and on its interactions with supra-spinal centres is not as developed as on the brain, mainly for methodological reasons. Due to a still insufficient spatial resolution, magnetic resonance imaging (MRI) does not allow a detailed study of small spinal structures. However, models recently developed from images of the diffusion tensor and magnetization transfer allowed a quantitative assessment of the main tracts in the spinal cord (myelination, number of fibres). However, these new methods of analysis still do not allow studying the functional characteristics of spinal networks and their ascending and descending interactions with the midbrain structures and the brain. Electrophysiological methods have been developed to study indirectly the human central nervous system and allowed a relatively detailed description of the organization of the spinal circuits and their excitability depending on the conditions of movement. These methods have also their limitations especially in the study of transmission pathways of descending motor command and interaction with the midbrain structures and basal ganglia. MRI and electrophysiology have been developed separately so far, but they are complementary and their combination would allow an anatomo-functional study of the interactions between the brain and the spinal cord. The team project is to bring together experts of these two methodological approaches and develop new models based on experimental data, which will allow a more detailed analysis of spinal networks and their interaction with supraspinal structures. This new approach will help us to better characterize the neural interactions between the brain and spinal cord in humans from an anatomical and functional point of view, and their changes after traumatic, vascular or degenerative lesion of the central nervous system affecting motor functions. A better understanding of the neural circuits involved in the sensory-motor control of the four limbs, and of the neural mechanisms underlying the post-lesion plasticity involved in the residual motility and/or the motor recovery will help, on one hand, to better characterize the causes of motor dysfunctions (earlier diagnosis of neurodegenerative damage) and, on the other hand, to better identify the therapeutic targets (functional rehabilitation). The team includes researchers, physicians and engineers who have an expertise in MRI, modelling and indirect electrophysiology and who have a position in a research or clinical department at the Pitié-Salpêtrière hospital, and young researchers and students who will be trained in both methodological techniques and then will have a double competence. The team will collaborate with physicians and researchers of other hospitals and with international institutes (Canada, Australia). This collaboration marks the beginning of a new team that will integrate the Laboratory of Functional Imaging (LIF, UMR_S 678 INSERM/Université Pierre et Marie Curie -UPMC- Paris 6, H. Benali) for the next five-year program 2014-2018. The funding request focuses on two short-term projects; each corresponding to the pursuit of scientific projects that were previously carried out in parallel by the group of electrophysiology (V. Marchand-Pauvert, Er 6 UPMC) and the MRI group (H. Benali, UMR_S 678 INSERM/UPMC). The merger of both groups will enable to combine the two methodological approaches and document the links between anatomy and function of the target structures.