HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Farmer, S F Articles by Stephens, J A Search for Related Content PubMed PubMed Citation Articles by Farmer, S F Articles by Stephens, J A

Department of Physiology, University College London.

1. The discharges of pairs of individual motor units were recorded from intrinsic hand muscles in man. Single motor unit recordings were obtained either when both members of the motor unit pair were within first dorsal interosseous muscle (1DI:1DI recordings) or where one motor unit was within 1DI and the other in second dorsal interosseous muscle (1DI:2DI recordings). The pairs of motor unit spike trains were cross-correlated in the time domain and the results compared to those of coherence analysis performed on the same spike train data. Central peaks were present in the cross-intensity functions, indicating the presence of common synaptic input to the motoneurone pair. Coherence analysis of these data indicated significant association between motor unit firing in the frequency ranges 1-12 and 16-32 Hz. 2. Analysis of sequential non-overlapping segments of data recorded from individual motor unit pairs, demonstrated that both the central cross-intensity peak and coherence in the frequency bands 1-12 and 16-32 Hz were consistent features throughout a long recording. In these sequential recordings, the size of the central cross-intensity peak and the maximal value of coherence in the frequency band 16-32 Hz covaried from segment to segment. Analysis of the entire population of motor unit pairs confirmed a positive relationship between the magnitude of peak coherence and the size of the central cross-intensity peak. 3. Voluntary sinusoidal co-modulation of the firing rates of pairs of individual motor units recorded from within 1DI was found to produce significant values of coherence corresponding to the frequency of the common modulation. However, firing rate co-modulation was not found to affect either the size of the central cross-intensity peak or the maximum value of coherence in the frequency band 16-32 Hz. 4. Pairs of single motor units were recorded from within 1DI and biceps brachii muscles of healthy subjects. The number and size of the central cross-intensity peaks and coherence peaks detected were compared for the two muscles. The incidence and size of central cross-intensity peaks and the incidence and magnitude of 16-32 Hz coherence peaks were both found to be greater for 1DI recordings when compared to biceps brachii recordings. 5. Single motor unit recordings were made from the intrinsic hand muscles of a patient with severe peripheral deafferentation. Time- and frequency-domain analysis of these recordings revealed cross-intensity peaks and frequency bands of coherence similar to those seen in healthy subjects.(ABSTRACT TRUNCATED AT 400 WORDS)

This article has been cited by other articles:

				T. W. Boonstra, M. Roerdink, A. Daffertshofer, B. van Vugt, G. van Werven, and P. J. Beek Low-Alcohol Doses Reduce Common 10- to 15-Hz Input to Bilateral Leg Muscles During Quiet Standing J Neurophysiol, October 1, 2008; 100(4): 2158 - 2164. [Abstract] [Full Text] [PDF]

				J. Lundbye-Jensen and J. B. Nielsen Central nervous adaptations following 1 wk of wrist and hand immobilization J Appl Physiol, July 1, 2008; 105(1): 139 - 151. [Abstract] [Full Text] [PDF]

				L. Patino, W. Omlor, V. Chakarov, M.-C. Hepp-Reymond, and R. Kristeva Absence of Gamma-Range Corticomuscular Coherence During Dynamic Force in a Deafferented Patient J Neurophysiol, April 1, 2008; 99(4): 1906 - 1916. [Abstract] [Full Text] [PDF]

				S. Erimaki and C. N. Christakos Coherent Motor Unit Rhythms in the 6-10 Hz Range During Time-Varying Voluntary Muscle Contractions: Neural Mechanism and Relation to Rhythmical Motor Control J Neurophysiol, February 1, 2008; 99(2): 473 - 483. [Abstract] [Full Text] [PDF]

				T. J. Dartnall, M. A. Nordstrom, and J. G. Semmler Motor Unit Synchronization Is Increased in Biceps Brachii After Exercise-Induced Damage to Elbow Flexor Muscles J Neurophysiol, February 1, 2008; 99(2): 1008 - 1019. [Abstract] [Full Text] [PDF]

				K. G. Keenan, D. Farina, F. G. Meyer, R. Merletti, and R. M. Enoka Sensitivity of the cross-correlaton between simulated surface EMGs for two muscles to detect motor unit synchronization J Appl Physiol, March 1, 2007; 102(3): 1193 - 1201. [Abstract] [Full Text] [PDF]

				S. F. Farmer, J. Gibbs, D. M. Halliday, L. M. Harrison, L. M. James, M. J. Mayston, and J. A. Stephens Changes in EMG coherence between long and short thumb abductor muscles during human development J. Physiol., March 1, 2007; 579(2): 389 - 402. [Abstract] [Full Text] [PDF]

				J. Duchateau, J. G. Semmler, and R. M. Enoka Training adaptations in the behavior of human motor units J Appl Physiol, December 1, 2006; 101(6): 1766 - 1775. [Abstract] [Full Text] [PDF]

				J. F. Yang and M. Gorassini Spinal and Brain Control of Human Walking: Implications for Retraining of Walking Neuroscientist, October 1, 2006; 12(5): 379 - 389. [Abstract] [PDF]

				S. A. Winges, J. A. Johnston, and M. Santello Muscle-Pair Specific Distribution and Grip-Type Modulation of Neural Common Input to Extrinsic Digit Flexors J Neurophysiol, September 1, 2006; 96(3): 1258 - 1266. [Abstract] [Full Text] [PDF]

				M. A. Perez, J. Lundbye-Jensen, and J. B. Nielsen Changes in corticospinal drive to spinal motoneurones following visuo-motor skill learning in humans J. Physiol., June 15, 2006; 573(3): 843 - 855. [Abstract] [Full Text] [PDF]

				S. N. Baker, M. Chiu, and E. E. Fetz Afferent Encoding of Central Oscillations in the Monkey Arm J Neurophysiol, June 1, 2006; 95(6): 3904 - 3910. [Abstract] [Full Text] [PDF]

				C. N. Christakos, N. A. Papadimitriou, and S. Erimaki Parallel Neuronal Mechanisms Underlying Physiological Force Tremor in Steady Muscle Contractions of Humans J Neurophysiol, January 1, 2006; 95(1): 53 - 66. [Abstract] [Full Text] [PDF]

				J. B. Nielsen, B. A. Conway, D. M. Halliday, M.-C. Perreault, and H. Hultborn Organization of common synaptic drive to motoneurones during fictive locomotion in the spinal cat J. Physiol., November 15, 2005; 569(1): 291 - 304. [Abstract] [Full Text] [PDF]

				C. J. Mottram, E. A. Christou, F. G. Meyer, and R. M. Enoka Frequency Modulation of Motor Unit Discharge Has Task-Dependent Effects on Fluctuations in Motor Output J Neurophysiol, October 1, 2005; 94(4): 2878 - 2887. [Abstract] [Full Text] [PDF]

				T. Gilbertson, E. Lalo, L. Doyle, V. Di Lazzaro, B. Cioni, and P. Brown Existing Motor State Is Favored at the Expense of New Movement during 13-35 Hz Oscillatory Synchrony in the Human Corticospinal System J. Neurosci., August 24, 2005; 25(34): 7771 - 7779. [Abstract] [Full Text] [PDF]

				N. L. Hansen, B. A. Conway, D. M. Halliday, S. Hansen, H. S. Pyndt, F. Biering-Sorensen, and J. B. Nielsen Reduction of Common Synaptic Drive to Ankle Dorsiflexor Motoneurons During Walking in Patients With Spinal Cord Lesion J Neurophysiol, August 1, 2005; 94(2): 934 - 942. [Abstract] [Full Text] [PDF]

				C. N. Riddle and S. N Baker Manipulation of peripheral neural feedback loops alters human corticomuscular coherence J. Physiol., July 15, 2005; 566(2): 625 - 639. [Abstract] [Full Text] [PDF]

				G. Mochizuki, T. D. Ivanova, and S. J. Garland Synchronization of Motor Units in Human Soleus Muscle During Standing Postural Tasks J Neurophysiol, July 1, 2005; 94(1): 62 - 69. [Abstract] [Full Text] [PDF]

				C. T. Moritz, E. A. Christou, F. G. Meyer, and R. M. Enoka Coherence at 16-32 Hz Can Be Caused by Short-Term Synchrony of Motor Units J Neurophysiol, July 1, 2005; 94(1): 105 - 118. [Abstract] [Full Text] [PDF]

				J. A. Johnston, S. A. Winges, and M. Santello Periodic Modulation of Motor-Unit Activity in Extrinsic Hand Muscles During Multidigit Grasping J Neurophysiol, July 1, 2005; 94(1): 206 - 218. [Abstract] [Full Text] [PDF]

				M. M. Sturman, D. E. Vaillancourt, and D. M. Corcos Effects of Aging on the Regularity of Physiological Tremor J Neurophysiol, June 1, 2005; 93(6): 3064 - 3074. [Abstract] [Full Text] [PDF]

				J. G. Semmler, M. V. Sale, F. G. Meyer, and M. A. Nordstrom Motor-Unit Coherence and Its Relation With Synchrony Are Influenced by Training J Neurophysiol, December 1, 2004; 92(6): 3320 - 3331. [Abstract] [Full Text] [PDF]

				N. L. Hansen and J. B. Nielsen The effect of transcranial magnetic stimulation and peripheral nerve stimulation on corticomuscular coherence in humans J. Physiol., November 15, 2004; 561(1): 295 - 306. [Abstract] [Full Text] [PDF]

				M. M. Sturman, D. E. Vaillancourt, L. V. Metman, R. A. E. Bakay, and D. M. Corcos Effects of subthalamic nucleus stimulation and medication on resting and postural tremor in Parkinson's disease Brain, September 1, 2004; 127(9): 2131 - 2143. [Abstract] [Full Text] [PDF]

				K. T. Reilly, M. A. Nordstrom, and M. H. Schieber Short-Term Synchronization Between Motor Units in Different Functional Subdivisions of the Human Flexor Digitorum Profundus Muscle J Neurophysiol, August 1, 2004; 92(2): 734 - 742. [Abstract] [Full Text] [PDF]

				J. M. Kilner, R. J. Fisher, and R. N. Lemon Coupling of Oscillatory Activity Between Muscles Is Strikingly Reduced in a Deafferented Subject Compared With Normal Controls J Neurophysiol, August 1, 2004; 92(2): 790 - 796. [Abstract] [Full Text] [PDF]

				A. Brovelli, M. Ding, A. Ledberg, Y. Chen, R. Nakamura, and S. L. Bressler Beta oscillations in a large-scale sensorimotor cortical network: Directional influences revealed by Granger causality PNAS, June 29, 2004; 101(26): 9849 - 9854. [Abstract] [Full Text] [PDF]

				A. M. Taylor and R. M. Enoka Quantification of the Factors That Influence Discharge Correlation in Model Motor Neurons J Neurophysiol, February 1, 2004; 91(2): 796 - 814. [Abstract] [Full Text] [PDF]

				S. F. Farmer, L. M. Harrison, M. J. Mayston, A. Parekh, L.M. James, and J. A. Stephens Abnormal cortex-muscle interactions in subjects with X-linked Kallmann's syndrome and mirror movements Brain, February 1, 2004; 127(2): 385 - 397. [Abstract] [Full Text] [PDF]

				J. J. Sosnoff, D. E. Vaillancourt, and K. M. Newell Aging and Rhythmical Force Output: Loss of Adaptive Control of Multiple Neural Oscillators J Neurophysiol, January 1, 2004; 91(1): 172 - 181. [Abstract] [Full Text]

				D. E. Vaillancourt, M. M. Sturman, L. Verhagen Metman, R. A.E. Bakay, and D. M. Corcos Deep brain stimulation of the VIM thalamic nucleus modifies several features of essential tremor Neurology, October 14, 2003; 61(7): 919 - 925. [Abstract] [Full Text] [PDF]

				P. Grosse and P. Brown Acoustic Startle Evokes Bilaterally Synchronous Oscillatory EMG Activity in the Healthy Human J Neurophysiol, September 1, 2003; 90(3): 1654 - 1661. [Abstract] [Full Text] [PDF]

				J. G. Semmler, K. W. Kornatz, and R. M. Enoka Motor-Unit Coherence During Isometric Contractions Is Greater in a Hand Muscle of Older Adults J Neurophysiol, August 1, 2003; 90(2): 1346 - 1349. [Abstract] [Full Text] [PDF]

				E. A. Christou, M. Shinohara, and R. M. Enoka Fluctuations in acceleration during voluntary contractions lead to greater impairment of movement accuracy in old adults J Appl Physiol, July 1, 2003; 95(1): 373 - 384. [Abstract] [Full Text] [PDF]

				D. M. Halliday, B. A. Conway, L.O.D. Christensen, N. L. Hansen, N. P. Petersen, and J. B. Nielsen Functional Coupling of Motor Units Is Modulated During Walking in Human Subjects J Neurophysiol, February 1, 2003; 89(2): 960 - 968. [Abstract] [Full Text] [PDF]

				P. Grosse, R. Guerrini, L. Parmeggiani, P. Bonanni, A. Pogosyan, and P. Brown Abnormal corticomuscular and intermuscular coupling in high-frequency rhythmic myoclonus Brain, February 1, 2003; 126(2): 326 - 342. [Abstract] [Full Text] [PDF]

				K. Toma, T. Mima, T. Matsuoka, C. Gerloff, T. Ohnishi, B. Koshy, F. Andres, and M. Hallett Movement Rate Effect on Activation and Functional Coupling of Motor Cortical Areas J Neurophysiol, December 1, 2002; 88(6): 3377 - 3385. [Abstract] [Full Text] [PDF]

				D. H. Laidlaw, S. K. Hunter, and R. M. Enoka Nonuniform activation of the agonist muscle does not covary with index finger acceleration in old adults J Appl Physiol, October 1, 2002; 93(4): 1400 - 1410. [Abstract] [Full Text] [PDF]

				S. Farmer Neural rhythms in Parkinson's disease Brain, June 1, 2002; 125(6): 1175 - 1176. [Full Text] [PDF]

				S. Salenius, S. Avikainen, S. Kaakkola, R. Hari, and P. Brown Defective cortical drive to muscle in Parkinson's disease and its improvement with levodopa Brain, March 1, 2002; 125(3): 491 - 500. [Abstract] [Full Text] [PDF]

				B. U. Kleine, D. F. Stegeman, D. Mund, and C. Anders Influence of motoneuron firing synchronization on SEMG characteristics in dependence of electrode position J Appl Physiol, October 1, 2001; 91(4): 1588 - 1599. [Abstract] [Full Text] [PDF]

				N. L. Hansen, S. Hansen, L.O.D. Christensen, N. T. Petersen, and J. B. Nielsen Synchronization of Lower Limb Motor Unit Activity During Walking in Human Subjects J Neurophysiol, September 1, 2001; 86(3): 1266 - 1276. [Abstract] [Full Text] [PDF]

				J. F. Marsden, P. Limousin-Dowsey, P. Ashby, P. Pollak, and P. Brown Subthalamic nucleus, sensorimotor cortex and muscle interrelationships in Parkinson's disease Brain, February 1, 2001; 124(2): 378 - 388. [Abstract] [Full Text] [PDF]

				B. Feige, A. Aertsen, and R. Kristeva-Feige Dynamic Synchronization Between Multiple Cortical Motor Areas and Muscle Activity in Phasic Voluntary Movements J Neurophysiol, November 1, 2000; 84(5): 2622 - 2629. [Abstract] [Full Text] [PDF]

				J. H. McAuley and C. D. Marsden Physiological and pathological tremors and rhythmic central motor control Brain, August 1, 2000; 123(8): 1545 - 1567. [Abstract] [Full Text] [PDF]

				J. F. Marsden, P. Ashby, P. Limousin-Dowsey, J. C. Rothwell, and P. Brown Coherence between cerebellar thalamus, cortex and muscle in man: Cerebellar thalamus interactions Brain, July 1, 2000; 123(7): 1459 - 1470. [Abstract] [Full Text] [PDF]

				M. A. J. Tijssen, J. F. Marsden, and P. Brown Frequency analysis of EMG activity in patients with idiopathic torticollis Brain, April 1, 2000; 123(4): 677 - 686. [Abstract] [Full Text] [PDF]

				D. M. Halliday Weak, Stochastic Temporal Correlation of Large-Scale Synaptic Input Is a Major Determinant of Neuronal Bandwidth Neural Comput., March 1, 2000; 12(3): 693 - 707. [Abstract] [Full Text]

				J. H. McAuley, T. C. Britton, J. C. Rothwell, L. J. Findley, and C. D. Marsden The timing of primary orthostatic tremor bursts has a task-specific plasticity Brain, February 1, 2000; 123(2): 254 - 266. [Abstract] [Full Text] [PDF]

				W. Yao, R. J. Fuglevand, and R. M. Enoka Motor-Unit Synchronization Increases EMG Amplitude and Decreases Force Steadiness of Simulated Contractions J Neurophysiol, January 1, 2000; 83(1): 441 - 452. [Abstract] [Full Text] [PDF]

				D. M. Halliday, B. A. Conway, S. F. Farmer, and J. R. Rosenberg Load-Independent Contributions From Motor-Unit Synchronization to Human Physiological Tremor J Neurophysiol, August 1, 1999; 82(2): 664 - 675. [Abstract] [Full Text] [PDF]

				P. Brown, S. F. Farmer, D. M. Halliday, J. Marsden, and J. R. Rosenberg Coherent cortical and muscle discharge in cortical myoclonus Brain, March 1, 1999; 122(3): 461 - 472. [Abstract] [Full Text] [PDF]

				P. Brown, S. Salenius, J. C. Rothwell, and R. Hari Cortical Correlate of the Piper Rhythm in Humans J Neurophysiol, December 1, 1998; 80(6): 2911 - 2917. [Abstract] [Full Text] [PDF]

				S. I. Perlmutter, M. A. Maier, and E. E. Fetz Activity of Spinal Interneurons and Their Effects on Forearm Muscles During Voluntary Wrist Movements in the Monkey J Neurophysiol, November 1, 1998; 80(5): 2475 - 2494. [Abstract] [Full Text] [PDF]

				S. Salenius, K. Portin, M. Kajola, R. Salmelin, and R. Hari Cortical Control of Human Motoneuron Firing During Isometric Contraction J Neurophysiol, June 1, 1997; 77(6): 3401 - 3405. [Abstract] [Full Text] [PDF]