Functional MR Imaging of the Cervical Spinal Cord by Use of Median Nerve Stimulation and Fist Clenching

Example of the time course of the MR imaging signal evoked by median nerve stimulation in a spinal cord voxel. During execution, the paradigm proceeds as follows: rest, right hand stimulation, rest, left hand stimulation, and so on. In each 30-s epoch, five images were acquired. The black dots and lines represent the raw data; the red curve, the model function fitted to the responses. Note the considerable left-right differences in amplitude despite the standardized stimulus intensity

Example of a statistical parametric map obtained in an fMR imaging session with median nerve stimulation. Sagittal views of the statistical parametric maps of the fMR imaging responses superimposed on the first acquired T2*-weighted image (A) and the spatially corresponding anatomic T1-weighted image section (B). The voxels displayed in colors of the activation pattern analyzed with a statistical threshold of P < .01. Vertebrae C7 and T1 are indicated. The color bar indicates the statistical Z values