Refining the sensory and motor ratunculus of the rat upper extremity using fMRI and direct nerve stimulation. Magn Reson Med 2007 Nov;58(5):901-9
Date
10/31/2007Pubmed ID
17969116Pubmed Central ID
PMC2519801DOI
10.1002/mrm.21408Scopus ID
2-s2.0-35948990086 (requires institutional sign-in at Scopus site) 29 CitationsAbstract
It is well understood that the different regions of the body have cortical representations in proportion to the degree of innervation. Our current understanding of the rat upper extremity has been enhanced using functional MRI (fMRI), but these studies are often limited to the rat forepaw. The purpose of this study is to describe a new technique that allows us to refine the sensory and motor representations in the cerebral cortex by surgically implanting electrodes on the major nerves of the rat upper extremity and providing direct electrical nerve stimulation while acquiring fMRI images. This technique was used to stimulate the ulnar, median, radial, and musculocutaneous nerves in the rat upper extremity using four different stimulation sequences that varied in frequency (5 Hz vs. 10 Hz) and current (0.5 mA vs. 1.0 mA). A distinct pattern of cortical activation was found for each nerve. The higher stimulation current resulted in a dramatic increase in the level of cortical activation. The higher stimulation frequency resulted in both increases and attenuation of cortical activation in different regions of the brain, depending on which nerve was stimulated.
Author List
Cho YR, Pawela CP, Li R, Kao D, Schulte ML, Runquist ML, Yan JG, Matloub HS, Jaradeh SS, Hudetz AG, Hyde JSAuthors
Hani S. Matloub MD Professor in the Plastic Surgery department at Medical College of WisconsinChristopher Pawela PhD Associate Professor in the Biomedical Engineering department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AnimalsElectric Stimulation
Electrodes
Forelimb
Magnetic Resonance Imaging
Monitoring, Physiologic
Rats