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Investigators:
- Vlodek Siemionow, Ph.D.
- Guang H. Yue, Ph.D.
- Jingzhi Liu, Ph.D.
- Yin Fang, Ph.D.
- Vinoth K. Ranganathan, M.S., M.B.A.
Collaborators:
- Vinod Sahgal, M.D., Dept. of Rehabilitation Medicine, CCF
- Leonard H. Calabrese, D.O., Dept. of Immunology, CCF
- Erik Pioro, M.D., Ph.D., Dept. of Neurology, CCF
- Janis Daly, Ph.D., Dept. of Neurology, CWRU
- Steve Reger, Ph.D., Dept. of Rehabilitation Medicine, CCF
Brief Description:
A central and still unresolved question for the neurosciences is how the brain participates in producing/controlling voluntary motor activity. In addition to the large volume of results that are based on animal experiments, several methods can be used to study aspects of neuromuscular control in humans. Functional magnetic resonance imaging (fMRI) is one such promising technique. It makes use of blood oxygenation level dependent (BOLD) contrast mechanism to identify areas of the brain that are activated during voluntary motor tasks. In hand motor activity, for example, the area of greatest activation is the motor cortex contralateral to the contracting (e.g. flexing) hand. The supplementary motor area and the ipsilateral motor cortex also clearly show cortical activity during hand flexion or extension. Using a multimodality approach, the areas of brain activation defined by fMRI can be superimposed on magnetic resonance images to represent regions of the brain with precise anatomical accuracy and high spatial resolution. This information, however, did not provide us in the time course of activity in the areas activated with voluntary action.
The electroencephalographic (EEG) activity related to muscle contraction, called the motor activity related potential (MRCP), provides us with information within a time resolution of milliseconds. Where in the brain do MRCPs come from? If the fMRI and the MRCP could be acquired simultaneously/acquired in synchrony, both spatial and temporal information could be more efficiently and accurately obtained. MRCPs represent EEG activity both before and after a voluntary motor action. To identify MRCPs, it is necessary to average the EEG signal with respect to the joint force changes. Just as evoked potentials on the EEG are time-locked to the external stimulus, the MRCPs must be time-locked to a phase of electromyographic activity, such as its onset. Major focus is devoted to the potential components that occur before muscle contraction begins, because they may relate to generation of the voluntary force generation. Averaged cortical potentials can be analyzed for consistency of negative waveforms, their temporal relationship to the force, and their topography. MRCPs begin with slowly rising negativity (the readiness potential) and progress to steeper, later negativity starting at about 100 msec before the onset of action (the negativity slope).
A central interest of our Neural Control Laboratory is to determine the differences in how the brain controls voluntary motor activity in healthy people as opposed to patients with motor disabilities. The relationship between MRCPs and muscle activation has not yet been well characterized. Our experimental studies, however, have shown that activation of the motor cortex varies linearly between (a) the magnitude of the MRCP and the level of voluntary muscle force, and (b) the amplitude of the MRCP and the variation in the rate of muscle force (dF/dt). We hypothesize that this linear relationship between cortical output and muscle activation is lost in case of patients after stroke and blocked or otherwise impaired in those with motor deficits. We are now expanding our studies to include patients with stroke, patients with chronic fatigue syndrome, elderly subjects, and other groups.
Key References:
Yue, G.H., Ranganathan, V., Siemionow, V. , Liu, J.Z., and Sahgal, V.: "Older Adults Exhibit a Reduced Ability to Fully Activate Their Biceps Brachii Muscle". Journal of Gerontology , Vol. 54A, No. 4, M249-M253, 1999.
Yue, G.H., Siemionow, V ., Liu, J.Z., Ranganathan, V., Sahgal, V.: "Brain Activation during Human Finger Extension and Flexion Movements" Brain Research , 856:291-300, 2000.
Siemionow, V. , Yue, G., Barnett, G.H., Sahgal. V., Heilbrun, M.P.: "Measurement of Tissue Electrical Impedance Confirms Stereotactically Localized Internal Segment of the Globus Pallidus during Surgery". Journal of Neuroscience Methods , 96:113-117, 2000.
Siemionow, V. , Yue, G.H., Ranganathan, V.K., Liu, J.Z., Sahgal, V.: “Relationship between motor activity-related cortical potential and voluntary muscle activation”. Experimental Brain Research , 133:303-312, 2000.
Fang, Y., Siemionow, V ., Sahgal V., Xiong, F. and Yue, H.G.: “ Greater Movement-Related Cortical Potential during Human Eccentric and Concentric Muscle Contractions”. J Neurophysiology, 86:1764-1772, 2001.
Ranganathan, V.K., Siemionow, V. , Liu, J.Z., Sahgal, V. and Yue, G.H.: “Skilled Finger Movement Exercise Improves Hand Function”, Journal of Gerontology: Medical Sciences , 56A:M518-M522, 2001.
Li, S., Latash, M.L., Yue, G.H., Siemionow, V . and Sahgal, V.: “The Effects of Stroke and Age on Finger Coordination in Multifinger Force Production Tasks”. Clinical Neurophysiology , 114(9):1646-55, 2003.
Karwowski, W., Siemionow, V . and Gielo-Perczak, K.: “Physical Neuroergonomics: The Human Brain in Control of Physical Work Activities”. Theor Issues in Ergon Sci , 4, 1-2:175-199, 2003.
Ranganathan, V.K., Siemionow, V. , Liu, J.Z., Sahgal, V. and Yue, G.H.: “From Mental Power to Muscle Power – Gaining Strength by Using the Mind”. Neuropsychologia, 42:944-956, 2004.
Siemionow, V ., Fang, Y., Calabrese, L., Sahgal V., and Yue, H.G.: “Alternations In Central Nervous System Signal During Motor Performance In Chronic Fatigue Syndrome”. Clin Neurophysiol , 115:2372-2381, 2004.
Daly, J., Fang, Y., Perepezko, E., Siemionow, V. , Yue, G.H.: ”Prolonged cognitive planning time, elevated cognitive effort, and relationship between coordination and motor control following stroke”. IEEE Transactions on Neural Systems and Rehabilitation Engineering , 14(2):168-171, 2006.
Liu, J.Z., Lewandowski, B., Karakasis, C., Yao , B., Siemionow, V., Sahgal, V., and Yue, G.H.: “Shifting of activation center in the brain during muscle fatigue: an explanation of minimal central fatigue?”., NeuroImage, 35:299–307, 2007.
Siemionow, V ., Fang, Y., Sahgal V., and Yue, H.G.: “Strong Mental Effort for Muscle Contraction is Associated with Elevated Excitability of Neurons in the Sensorimotor Cortex”. Experimental Brain Research. Prepared for submission.