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Common input to different regions of biceps brachii long head

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Abstract

The purpose of the experiment was to compare the level of synchronization exhibited by pairs of motor units located within and between functionally distinct regions of the biceps brachii muscle. Pairs of single motor units were recorded from seven subjects using separate electrodes located in the lateral and medial aspects of the long head of biceps brachii. Participants were required to exert a combination of flexion and supination torques so that both motor units discharged at approximately 10 pps for ≥200 s and the level of motor unit synchronization could be quantified. When motor unit recordings were sufficiently stable at the completion of this synchrony task, a series of ramp contractions with multiple combinations of flexion and supination torques were performed to characterize the recruitment thresholds of the motor units. Common input strength (CIS) was significantly greater (< 0.01) for the within-region pairs of motor units (0.28 extra sync. imps/s, n = 26) than for the between-region pairs (0.13 extra sync. imps/s, n = 18), but did not differ significantly for the 12 within-region pairs from the lateral head and 14 from the medial head (0.27 vs. 0.29 extra sync. imps/s; = 0.83). Recruitment thresholds were measured for 33 motor units, but there was only a weak association between CIS and the respective recruitment patterns for motor unit pairs (n = 9). The present investigation provides evidence of a differential distribution of synaptic input across the biceps brachii motor neuron pool, but this appears to have minimal association with the recruitment patterns for individual motor units.

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References

  • Athwal GS, Steinmann SP, Rispoli DM (2007) The distal biceps tendon: footprint and relevant clinical anatomy. J Hand Surg [Am] 32:1225–1229

    Article  Google Scholar 

  • Barry BK, Riley ZA, Pascoe MA, Enoka RM (2008) A spinal pathway between synergists can modulate activity in human elbow flexor muscles. Exp Brain Res 190:347–359

    Article  PubMed  Google Scholar 

  • Bremner FD, Baker JR, Stephens JA (1991) Effect of task on the degree of synchronization of intrinsic hand muscle motor units in man. J Neurophysiol 66:2072–2083

    PubMed  CAS  Google Scholar 

  • Butler JE, Gandevia SC (2008) The output from human inspiratory motoneurone pools. J Physiol 586:1257–1264

    Article  PubMed  CAS  Google Scholar 

  • Butler TJ, Kilbreath SL, Gorman RB, Gandevia SC (2005) Selective recruitment of single motor units in human flexor digitorum superficialis muscle during flexion of individual fingers. J Physiol 567:301–309

    Article  PubMed  CAS  Google Scholar 

  • Cavallari P, Katz R (1989) Pattern of projections of group I afferents from forearm muscles to motoneurones supplying biceps and triceps muscles in man. Exp Brain Res 78:465–478

    Article  PubMed  CAS  Google Scholar 

  • Christou EA, Rudroff T, Enoka JA, Meyer F, Enoka RM (2007) Discharge rate during low-force isometric contractions influences motor unit coherence below 15 Hz but not motor unit synchronization. Exp Brain Res 178:285–295

    Article  PubMed  Google Scholar 

  • Conway BA, Halliday DM, Farmer SF, Shahani U, Maas P, Weir AI, Rosenberg JR (1995) Synchronization between motor cortex and spinal motoneuronal pool during the performance of a maintained motor task in man. J Physiol 489(Pt 3):917–924

    PubMed  CAS  Google Scholar 

  • Cope TC, Sokoloff AJ (1999) Orderly recruitment tested across muscle boundaries. Prog Brain Res 123:177–190

    Article  PubMed  CAS  Google Scholar 

  • Dartnall TJ, Nordstrom MA, Semmler JG (2008) Motor unit synchronization is increased in biceps brachii after exercise-induced damage to elbow flexor muscles. J Neurophysiol 99:1008–1019

    Article  PubMed  Google Scholar 

  • Datta AK, Stephens JA (1990) Synchronization of motor unit activity during voluntary contraction in man. J Physiol 422:397–419

    PubMed  CAS  Google Scholar 

  • Datta AK, Farmer SF, Stephens JA (1991) Central nervous pathways underlying synchronization of human motor unit firing studied during voluntary contractions. J Physiol 432:401–425

    PubMed  CAS  Google Scholar 

  • De Luca CJ, Roy AM, Erim Z (1993) Synchronization of motor-unit firings in several human muscles. J Neurophysiol 70:2010–2023

    PubMed  Google Scholar 

  • De Troyer A, Kirkwood PA, Wilson TA (2005) Respiratory action of the intercostal muscles. Physiol Rev 85:717–756

    Article  PubMed  Google Scholar 

  • Eames MH, Bain GI, Fogg QA, van Riet RP (2007) Distal biceps tendon anatomy: a cadaveric study. J Bone Joint Surg Am 89:1044–1049

    Article  PubMed  CAS  Google Scholar 

  • Ellaway PH (1978) Cumulative sum technique and its application to the analysis of peristimulus time histograms. Electroencephalogr Clin Neurophysiol 45:302–304

    Article  PubMed  CAS  Google Scholar 

  • Ellaway PH, Murthy KS (1985) The origins and characteristics of cross-correlated activity between gamma-motoneurones in the cat. Q J Exp Physiol 70:219–232

    PubMed  CAS  Google Scholar 

  • English AW, Letbetter WD (1981) Intramuscular “compartmentalization” of the cat biceps femoris and semitendinosus muscles: anatomy and EMG patterns. Abstr Soc Neurosci 7:557

    Google Scholar 

  • Epstein M, Wong M, Herzog W (2006) Should tendon and aponeurosis be considered in series? J Biomech 39:2020–2025

    Article  PubMed  Google Scholar 

  • Ettema G, Styles G, Kippers V (1998) The moment arms of 23 muscle segments of the upper limb with varying elbow and forearm positions: implications for motor control. Hum Mov Sci 17:201–220

    Article  Google Scholar 

  • Farmer SF, Bremner FD, Halliday DM, Rosenberg JR, Stephens JA (1993a) The frequency content of common synaptic inputs to motoneurones studied during voluntary isometric contraction in man. J Physiol 470:127–155

    PubMed  CAS  Google Scholar 

  • Farmer SF, Swash M, Ingram DA, Stephens JA (1993b) Changes in motor unit synchronization following central nervous lesions in man. J Physiol 463:83–105

    PubMed  CAS  Google Scholar 

  • Henneman E, Somjen G, Carpenter DO (1965) Functional significance of cell size in spinal motoneurons. J Neurophysiol 28:560–580

    PubMed  CAS  Google Scholar 

  • Herrmann U, Flanders M (1998) Directional tuning of single motor units. J Neurosci 18:8402–8416

    PubMed  CAS  Google Scholar 

  • Katz R, Penicaud A, Rossi A (1991) Reciprocal Ia inhibition between elbow flexors and extensors in the human. J Physiol 437:269–286

    PubMed  CAS  Google Scholar 

  • Keen DA, Fuglevand AJ (2003) Role of intertendinous connections in distribution of force in the human extensor digitorum muscle. Muscle Nerve 28:614–622

    Article  PubMed  Google Scholar 

  • Keen DA, Fuglevand AJ (2004a) Assessment of synchrony in motor unit pools with different presumed levels of corticomotoneuronal input. Abstr Soc Neurosci #992.5

  • Keen DA, Fuglevand AJ (2004b) Common input to motor neurons innervating the same and different compartments of the human extensor digitorum muscle. J Neurophysiol 91:57–62

    Article  PubMed  Google Scholar 

  • Keen DA, Fuglevand AJ (2004c) Distribution of motor unit force in human extensor digitorum assessed by spike-triggered averaging and intraneural microstimulation. J Neurophysiol 91:2515–2523

    Article  PubMed  Google Scholar 

  • Kilbreath SL, Gandevia SC (1994) Limited independent flexion of the thumb and fingers in human subjects. J Physiol 479(Pt 3):487–497

    PubMed  Google Scholar 

  • Kilbreath SL, Gorman RB, Raymond J, Gandevia SC (2002) Distribution of the forces produced by motor unit activity in the human flexor digitorum profundus. J Physiol 543:289–296

    Article  PubMed  CAS  Google Scholar 

  • Kim M-S, Masakado Y, Tomita Y, Chino N, Pae YS, Lee K (2001) Synchronization of single motor units during voluntary contractions in the upper and lower extremities. Clin Neurophysiol 112:1243–1249

    Article  PubMed  CAS  Google Scholar 

  • Kirkwood PA, Sears TA, Stagg D, Westgaard RH (1982a) The spatial distribution of synchronization of intercostal motoneurones in the cat. J Physiol 327:137–155

    PubMed  CAS  Google Scholar 

  • Kirkwood PA, Sears TA, Tuck DL, Westgaard RH (1982b) Variations in the time course of the synchronization of intercostal motoneurones in the cat. J Physiol 327:105–135

    PubMed  CAS  Google Scholar 

  • Mattei B, Schmied A, Mazzocchio R, Decchi B, Rossi A, Vedel JP (2003) Pharmacologically induced enhancement of recurrent inhibition in humans: effects on motoneurone discharge patterns. J Physiol 548:615–629

    Article  PubMed  CAS  Google Scholar 

  • McIsaac TL, Fuglevand AJ (2007) Motor unit synchrony within and across compartments of the human flexor digitorum superficialis. J Neurophysiol 97:550–556

    Article  PubMed  Google Scholar 

  • McKiernan BJ, Marcario JK, Karrer JH, Cheney PD (1998) Corticomotoneuronal postspike effects in shoulder, elbow, wrist, digit, and intrinsic hand muscles during a reach and prehension task. J Neurophysiol 80:1961–1980

    PubMed  CAS  Google Scholar 

  • Monti RJ, Roy RR, Hodgson JA, Edgerton VR (1999) Transmission of forces within mammalian skeletal muscles. J Biomech 32:371–380

    Article  PubMed  CAS  Google Scholar 

  • Naito A, Shindo M, Miyasaka T, Sun YJ, Morita H (1996) Inhibitory projection from brachioradialis to biceps brachii motoneurones in human. Exp Brain Res 111:483–486

    Article  PubMed  CAS  Google Scholar 

  • Naito A, Shindo M, Miyasaka T, Sun YJ, Momoi H, Chishima M (1998) Inhibitory projections from pronator teres to biceps brachii motoneurones in human. Exp Brain Res 121:99–102

    Article  PubMed  CAS  Google Scholar 

  • Nielsen J, Kagamihara Y (1994) Synchronization of human leg motor units during co-contraction in man. Exp Brain Res 102:84–94

    PubMed  CAS  Google Scholar 

  • Nordstrom MA, Fuglevand AJ, Enoka RM (1992) Estimating the strength of common input to human motoneurons from the cross-correlogram. J Physiol 453:547–574

    PubMed  CAS  Google Scholar 

  • Palmer E, Ashby P (1992) Corticospinal projections to upper limb motoneurones in humans. J Physiol 448:397–412

    PubMed  CAS  Google Scholar 

  • Reilly KT, Schieber MH (2003) Incomplete functional subdivision of the human multitendoned finger muscle flexor digitorum profundus: an electromyographic study. J Neurophysiol 90:2560–2570

    Article  PubMed  Google Scholar 

  • Reilly KT, Nordstrom MA, Schieber MH (2004) Short-term synchronization between motor units in different functional subdivisions of the human flexor digitorum profundus muscle. J Neurophysiol 92:734–742

    Article  PubMed  Google Scholar 

  • Riek S, Bawa P (1992) Recruitment of motor units in human forearm extensors. J Neurophysiol 68:100–108

    PubMed  CAS  Google Scholar 

  • Schmied A, Ivarsson C, Fetz EE (1993) Short-term synchronization of motor units in human extensor digitorum communis muscle: relation to contractile properties and voluntary control. Exp Brain Res 97:159–172

    Article  PubMed  CAS  Google Scholar 

  • Sears TA, Stagg D (1976) Short-term synchronization of intercostal motoneurone activity. J Physiol 263:357–381

    PubMed  CAS  Google Scholar 

  • Segal RL (1992) Neuromuscular compartments in the human biceps brachii muscle. Neurosci Lett 140:98–102

    Article  PubMed  CAS  Google Scholar 

  • Semmler JG, Steege JW, Kornatz KW, Enoka RM (2000) Motor-unit synchronization is not responsible for larger motor-unit forces in old adults. J Neurophysiol 84:358–366

    PubMed  CAS  Google Scholar 

  • Semmler JG, Kornatz KW, Dinenno DV, Zhou S, Enoka RM (2002) Motor unit synchronisation is enhanced during slow lengthening contractions of a hand muscle. J Physiol 545:681–695

    Article  PubMed  CAS  Google Scholar 

  • Tanji J, Kato M (1973) Recruitment of motor units in voluntary contraction of a finger muscle in man. Exp Neurol 40:759–770

    Article  PubMed  CAS  Google Scholar 

  • Taylor AM, Enoka RM (2004) Quantification of the factors that influence discharge correlation in model motor neurons. J Neurophysiol 91:796–814

    Article  PubMed  Google Scholar 

  • ter Haar Romeny BM, Denier van der Gon JJ, Gielen CC (1982) Changes in recruitment order of motor units in the human biceps muscle. Exp Neurol 78:360–368

    Article  PubMed  CAS  Google Scholar 

  • ter Haar Romeny BM, van der Gon JJ, Gielen CC (1984) Relation between location of a motor unit in the human biceps brachii and its critical firing levels for different tasks. Exp Neurol 85:631–650

    Article  PubMed  CAS  Google Scholar 

  • Turker KS, Powers RK (2001) Effects of common excitatory and inhibitory inputs on motoneuron synchronization. J Neurophysiol 86:2807–2822

    PubMed  CAS  Google Scholar 

  • Turker KS, Powers RK (2002) The effects of common input characteristics and discharge rate on synchronization in rat hypoglossal motoneurones. J Physiol 541:245–260

    Article  PubMed  CAS  Google Scholar 

  • van Bolhuis BM, Medendorp WP, Gielen CC (1997) Motor unit firing behavior in human arm flexor muscles during sinusoidal isometric contractions and movements. Exp Brain Res 117:120–130

    Article  PubMed  Google Scholar 

  • van Zuylen EJ, Gielen CC, Denier van der Gon JJ (1988) Coordination and inhomogeneous activation of human arm muscles during isometric torques. J Neurophysiol 60:1523–1548

    PubMed  Google Scholar 

  • Wiegner AW, Wierzbicka MM (1987) A method for assessing significance of peaks in cross-correlation histograms. J Neurosci Methods 22:125–131

    Article  PubMed  CAS  Google Scholar 

  • Windhorst U, Hamm TM, Stuart DG (1989) On the function of muscle and reflex partitioning. Behav Brain Sci 12:629–681

    Article  Google Scholar 

  • Winges SA, Santello M (2004) Common input to motor units of digit flexors during multi-digit grasping. J Neurophysiol 92:3210–3220

    Article  PubMed  Google Scholar 

  • Yu WS, Kilbreath SL, Fitzpatrick RC, Gandevia SC (2007) Thumb and finger forces produced by motor units in the long flexor of the human thumb. J Physiol 583:1145–1154

    Article  PubMed  CAS  Google Scholar 

  • Yucesoy CA, Koopman BH, Baan GC, Grootenboer HJ, Huijing PA (2003) Effects of inter- and extramuscular myofascial force transmission on adjacent synergistic muscles: assessment by experiments and finite-element modeling. J Biomech 36:1797–1811

    Article  PubMed  Google Scholar 

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Acknowledgments

This research was supported by: Australian Research Council to SR and RGC, National Health and Medical Research Council to RGC, and NIH (NS042734) to RME.

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Correspondence to Benjamin K. Barry.

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Barry, B.K., Pascoe, M.A., Riek, S. et al. Common input to different regions of biceps brachii long head. Exp Brain Res 193, 351–359 (2009). https://doi.org/10.1007/s00221-008-1631-2

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  • DOI: https://doi.org/10.1007/s00221-008-1631-2

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