Kathleen M. Osborn Chair in Molecular and Integrative Physiology
State University of New York, 1975
Neurophysiology - motor control
Specific research interests include: 1) brain mechanisms underlying the control of voluntary movements, and 2) recovery of motor function following brain injury.
Modern neurophysiological techniques are used to investigate the function of neurons in the cerebral cortex and brainstem. The electrical discharges of single neurons are recorded during various movement tasks. Computerized analysis techniques are used to reveal the functional contribution of a neuron to movement.
Brain control of movement and movement disorders
Recent work has focused on the use of stimulus triggered averaging of EMG activity to characterize the motoneuronal targets of corticospinal neurons. Our recent findings show that the majority of single corticospinal neurons involved in arm reach and grasp tasks influence muscles of both distal and proximal joints acting as a functional synergy during some phase of the reaching task .
Figure 1. Stimulus triggered averages from 24 forelimb muscles generated from the 15 µA stimuli applied to primary motor cortex (M1) during performance of a reach-to-grasp task. The averages show clear poststimulus facilitation in muscles at both proximal (shoulder and elbow) and distal (wrist and digit) joints. Poststimulus suppression is also present in FCU and PL. Using this approach, the representation of individual muscles and muscle groups in M1 was mapped.
In other work, stimulus triggered averaging of EMG activity has been used to map primary motor cortex with respect to 24 muscles of the forelimb (Figure1). Collapsing maps for all distal muscles and all proximal muscles reveals one of the consistent features in the intra-areal representation of the forelimb in primary motor cortex (see Fig. 2). A similar approach has been used to map secondary motor areas (PMv, PMd, SMA). This work forms the foundation for investigating recovery of motor function following brain injury associated with stroke.
Figure 2. Representation of distal (blue) and proximal (red) muscles in primary motor cortex constructed from output effects in stimulus triggered averages computed at 15 microamps during a reach and grasp task. Primary motor cortex is unfolded and represented in two dimensions. The purple area represents sites which evoked effects in combinations of proximal and distal muscles. These sites may be particularly important in mediating coactivation of distal and proximal muscles commonly observed during reach and grasp. From Park, Belhaj-Saif, Gordon and Cheney, J. Neuroscience 21: 2784-2792, 2001.
McKiernan, B.J., Marcario, J.K., Hill-Karrer, J. and Cheney, P.D. Correlations between the magnitude of Corticomotoneuronal cell postspike effects and the strength of cell-target muscle covariation. J. Neurophysiol. 83: 99-115, 2000
Park, M.C., Belhaj-Saif, A. and Cheney, P.D. Chronic recording of EMG activity from large numbers of forelimb muscles in awake macaque monkeys. J. Neurosci. Methods 15: 153-160, 2000.
Cheney, P.D., Park, M.C. Belhaj-Saïf, A. Hill-Karrer, J. McKiernan, B.J. and Marcario, J. K. Cortical motor areas an their properties: implications for neuroprosthetics. Prog. Brain Res. 128: 135-160, 2000
Park, M.C., Belhaj-Saif, A. and Cheney, P.D. Consistent features in the forelimb representation of primary motor cortex of rhesus macaques. J. Neurosci. 21: 2784-2792, 2001.
Cheney, P.D. Electrophysiological Methods for Mapping Brain Motor Circuits. In: Brain Mapping: The Methods, Second Edition, A. W. Toga and J. C. Mazziotta (Eds.), New York, NY: Academic Press, 2002.
Park, M.C., Belhaj-Saif, A. and Cheney, P.D. Distribution and properties of poststimulus effects in proximal and distal forelimb muscles from primary motor cortex in rhesus macaques. J. Neurophysiol. 92: 2968-2984, 2004.
Marcario, J.K., Manaye, K.F., SantaCruz, K.S., Mouton, P.R., Berman, N.E.J., and Cheney, P.D. Severe subcortical degeneration in macaques infected with neurovirulent simian immunodeficiency virus. J. Neurovirol. 10: 387-399, 2004.
Cheney, P.D., Belhaj-Saïf, A. and Boudrias, M.H. Principles of Corticospinal System Organization and Function. In: Handbook of Clinical Neurophysiology, Vol. 4, Clinical Neurophysiology of Motor Neuron Diseases, A. Eisen, Editor, New York, NY: Elsevier Science, pp. 59-96, 2004.
Boudrias, M.H, Belhaj-Saïf and Cheney, P.D. Output Properties of Supplementary Motor Area (SMA) in Rhesus Macaques. Cerebral Cortex 16: 632-638, 2006.
Marcario, J.K., Riazi, M., Adany, A., Kenjale, H., Fleming, H.K., Marquis, M., Nemon, O., Mayo, M., Yankee, T., Narayan, O., and Cheney, P.D. Effect of morphine on the neuropathogenesis of SIVmac infection in Indian rhesus macaques. J. Neuroimmune Pharmacology 3: 12-25, 2008.
Griffin, D.M., Hudson, H.M., Belhaj-Sa?f, A., McKiernan, B.J. and Cheney, P.D. Do Corticomotoneuronal Cells Predict Target Muscle EMG Activity? J. Neurophysiol. 99: 1169-1186, 2008.
Cheney, P.D., Riazi, M. and Marcario, J.K. Behavioral and Neurophysiological Hallmarks of SIV Infection in Macaque Monkeys. J. Neurovirol. 14: 301-308, 2008.
Riazi, M., Marcario, J.K., Samson, F.K., Kenjale, H., Adany, I., Staggs, V., Ledford, E., Marquis, J., Narayan, O., and Cheney, P.D. Rhesus macaque model of chronic opiate dependence and neuro-AIDS: longitudinal assessment of auditory brainstem responses and visual evoked potentials. J. Neuroimmune Pharmacology 4: 260-275, 2009.
Griffin, D.M., Hudson, H.M., Belhaj-Sa?f, A. and Cheney, P.D. Stability of output effects from motor cortex to forelimb muscles in primates. J. Neurosci., 29: 1915-1927, 2009.
Boudrias, M.H., Lee, S.P., Svojanovsky, S. and Cheney, P.D. Forelimb muscle representations and output properties of the motor areas in the mesial wall of rhesus macaques. Cerebral Cortex, in press, 2009.
Boudrias, M.H., McPherson, R.L., Frost, S.B. and Cheney, P.D. Output properties and organization of the forelimb representation of motor areas on the lateral aspect of the hemisphere in rhesus macaques. Cerebral Cortex, in press, 2009.