eMedicine Specialties > Neurology > Electroencephalography and Evoked Potentials

Motor Evoked Potentials: Multimedia

Author: Jasvinder Chawla, MBBS, MD, MBA, Associate Professor of Neurology, Director of Neurology Residency Training Program, Director of Clinical Neurophysiology Laboratory, Assistant Director of Neurology Clerkship Program, Department of Neurology, Loyola University Medical Center
Contributor Information and Disclosures

Updated: Nov 25, 2008

Multimedia

Double-pulse study. Using a common single coil, a...
(Enlarge Image)
Media file 1: Double-pulse study. Using a common single coil, a conditioning stimulus (1) is given over the target hemisphere a short delay prior to a test stimulus (2) over the same location. The conditioning effect is evaluated by comparing conditioned responses to baseline responses that are obtained without conditioning stimulus. This allows measurement of intracortical inhibition and facilitation.
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Double-pulse study. Using a common single coil, a...

Double-pulse study. Using a common single coil, a conditioning stimulus (1) is given over the target hemisphere a short delay prior to a test stimulus (2) over the same location. The conditioning effect is evaluated by comparing conditioned responses to baseline responses that are obtained without conditioning stimulus. This allows measurement of intracortical inhibition and facilitation.

Interhemispheric conditioning study. A conditioni...
(Enlarge Image)
Media file 2: Interhemispheric conditioning study. A conditioning stimulus (1) is given over the contralateral hemisphere a short delay prior to a test stimulus (2) over the target hemisphere. The conditioning effect is evaluated by comparing conditioned responses to baseline responses that are obtained without a conditioning stimulus. This allows measurement of transcallosal inhibition or excitation.
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Interhemispheric conditioning study. A conditioni...

Interhemispheric conditioning study. A conditioning stimulus (1) is given over the contralateral hemisphere a short delay prior to a test stimulus (2) over the target hemisphere. The conditioning effect is evaluated by comparing conditioned responses to baseline responses that are obtained without a conditioning stimulus. This allows measurement of transcallosal inhibition or excitation.

Example of motor map obtained by transcranial mag...
(Enlarge Image)
Media file 3: Example of motor map obtained by transcranial magnetic stimulation using a stereotactic technique. The TMS map is represented in red. It is compared to the map that is obtained with functional MRI in green. The overlap of TMS and functional MRI maps is represented in yellow. The 2 techniques can provide complementary information on motor control.
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Example of motor map obtained by transcranial mag...

Example of motor map obtained by transcranial magnetic stimulation using a stereotactic technique. The TMS map is represented in red. It is compared to the map that is obtained with functional MRI in green. The overlap of TMS and functional MRI maps is represented in yellow. The 2 techniques can provide complementary information on motor control.

More on Motor Evoked Potentials

References
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References

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Further Reading

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Keywords

motor evoked potentials, MEPs, electrical stimulation of motor cortex, corticospinal connections, transcranial electrical stimulation, TES, transcranial magnetic stimulation, TMS, pyramidal tract, stimulation of the central nervous system, stimulation of the CNS, magnetic stimulation, electrical stimulation, electrophysiology of motor evoked potentials, electrophysiology of MEPs, clinical applications of motor evoked potentials, clinical applications of MEPs

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Contributor Information and Disclosures

Author

Jasvinder Chawla, MBBS, MD, MBA, Associate Professor of Neurology, Director of Neurology Residency Training Program, Director of Clinical Neurophysiology Laboratory, Assistant Director of Neurology Clerkship Program, Department of Neurology, Loyola University Medical Center
Jasvinder Chawla, MBBS, MD, MBA is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American Clinical Neurophysiology Society, and American Medical Association
Disclosure: Nothing to disclose.

Medical Editor

Sydney Louis, MB, BCh, MD, Emeritus Professor, Department of Neurology, Brown University School of Medicine
Sydney Louis, MB, BCh, MD is a member of the following medical societies: American Academy of Neurology
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Norberto Alvarez, MD, Assistant Professor, Department of Neurology, Harvard Medical School; Consulting Staff, Department of Neurology, Boston Children's Hospital
Norberto Alvarez, MD is a member of the following medical societies: American Academy of Neurology, American Epilepsy Society, and Child Neurology Society
Disclosure: Nothing to disclose.

CME Editor

Matthew J Baker, MD, Consulting Staff, Collier Neurologic Specialists, Naples Community Hospital
Matthew J Baker, MD is a member of the following medical societies: American Academy of Neurology
Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

 
 
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