MR compatible force sensing system for real-time monitoring of wrist moments during fMRI testing

The ability to monitor and quantify force exertions made by individuals during fMRI scans of the brain would provide researchers and clinicians a standardized, well-controlled behavioral task that could improve the repeatability and accuracy of imaging studies. In this work, we present a MRI compatible wrist module that is capable of measuring isometric forces generated at the hand and joint moments along wrist flexion-extension and wrist ulna-radial deviation axes. Joint moments measured by the system can be visually displayed to the individual and used during target matching tasks. In a small set of pilot tests, it was found that the noise on the force and moment signals were not affected by the magnetic fields nor were the fMRI images influenced by the presence of the device. In future studies, we plan to use the wrist module to investigate cortical reorganization in stroke patients following prolonged neurorehabilitation.