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Functional magnetic resonance imaging(fMRI) has been widely used to study the neural basis of perception, cognition and emotion,as it is non-invasive. Such studies have traditionally focused on human brain function. As the important part of the central nervous system, it will be very useful to apply the fMRI technology to the spinal cord. The diagnosis and treatment of many diseases will be hopeful.Different from the human brain, the application of fMRI to spinal cord is much challenging. The main difficulties facing researchers attempting to image the spinal cord are its small cross-sectional area, the influence of physiological effects that displace the cord,etc. As a result, the spinal cord fMRI is effected by the physiological noise, and displays false-positive activation in the process. To solve the problem, we proposed a method to model the physiological, and try to remove the aliasing signal. Based on the GLM(general linear model, GLM),we try to model the signal the heart fluctuation and respiration signal as additional terms to the Fourier expansion used by the RETROICOR., the signals are modeled using sin/cos term and assigned according to the cycle that are in the physiological cycle. We are trying to removing the noise signal in the frequency domain. Through using this method, the activation map is obtained in the medetomidine-sedated rat.To analyze the activated region during the electrical stimulation, we do a functional connectivity in the resting-state data. The results show that there is connectivity during distinct region, and show a functional and structural connectivity. And synchronized LFF of BOLD signal are observed in the cortices and caudate-putamen of the two hemispheres symmetrically, but there is no such feature in the thalamus. It’s interesting that the motor-sensory system showed significant hemisphere predominance during resting state. Compared to the resting-state connectivity, the connectivity is lower in the stimulated animals,which may be used as the sign of the sensory pathway.
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