title: Bilateral force transients in the upper limbs evoked by single-pulse microstimulation in the pontomedullary reticular formation.
abstract: Neurons in the pontomedullary reticular formation (PMRF) give rise to the reticulospinal tract. The motor output of the PMRF was investigated using stimulus-triggered averaging of electromyography (EMG) and force recordings in two monkeys (M. fascicularis). EMG was recorded from 12 pairs of upper limb muscles, and forces were detected using two isometric force-sensitive handles. Of 150 stimulation sites, 105 (70.0%) produced significant force responses, and 139 (92.5%) produced significant EMG responses. Based on the average flexor EMG onset latency of 8.3 ms and average force onset latency of 15.9 ms poststimulation, an electromechanical delay of ∼7.6 ms was calculated. The magnitude of force responses (∼10 mN) was correlated with the average change in EMG activity (P < 0.001). A multivariate linear regression analysis was used to estimate the contribution of each muscle to force generation, with flexors and extensors exhibiting antagonistic effects. A predominant force output pattern of ipsilateral flexion and contralateral extension was observed in response to PMRF stimulation, with 65.3% of significant ipsilateral force responses directed medially and posteriorly (P < 0.001) and 78.6% of contralateral responses directed laterally and anteriorly (P < 0.001). This novel approach permits direct measurement of force outputs evoked by central nervous system microstimulation. Despite the small magnitude of poststimulus EMG effects, low-intensity single-pulse microstimulation of the PMRF evoked detectable forces. The forces, showing the combined effect of all muscle activity in the arms, are consistent with reciprocal pattern of force outputs from the PMRF detectable with stimulus-triggered averaging of EMG.
authors: Neuroscience Graduate Program, The Ohio State University, Columbus, Ohio; and.
authors: Thomas J
authors: TJ
authors: Hirschauer
authors: Neuroscience Graduate Program, The Ohio State University, Columbus, Ohio; and Physical Therapy Division, The Ohio State University, Columbus, Ohio buford.5@osu.edu.
authors: John A
authors: JA
authors: Buford
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D004576:Electromyography; D008252:Macaca fascicularis; D008297:Male; D055595:Mechanical Phenomena; D008526:Medulla Oblongata / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D065821:Pontine Tegmentum / Q000502:physiology*; D034941:Upper Extremity / Q000502:physiology
keywords: electrophysiology; macaque; reticulospinal; stimulus-triggered averaging
references: J Neurophysiol. 1984 Oct;52(4):653-75
references: 6491711
references: J Neurophysiol. 1970 May;33(3):382-92
references: 4985724
references: J Neurophysiol. 1985 Oct;54(4):978-87
references: 4067629
references: J Neurophysiol. 1990 Sep;64(3):767-81
references: 2230923
references: J Neurophysiol. 1990 Sep;64(3):782-95
references: 2230924
references: Eur J Appl Physiol Occup Physiol. 1991;63(2):124-8
references: 1748102
references: Science. 1992 Jun 19;256(5064):1692-5
references: 1609282
references: J Neurophysiol. 1994 Dec;72(6):2648-64
references: 7897481
references: Brain. 1995 Apr;118 ( Pt 2):495-510
references: 7735890
references: Annu Rev Physiol. 1979;41:127-40
references: 373586
references: Exp Brain Res. 1979 Jun 1;36(1):1-20
references: 467530
references: Acta Physiol Scand. 1979 Jul;106(3):241-8
references: 506761
references: Acta Neurobiol Exp (Wars). 1980;40(4):741-55
references: 7435273
references: Exp Brain Res. 1981;42(1):81-8
references: 7215512
references: J Comp Neurol. 1984 Jan 10;222(2):265-300
references: 6365984
references: Neuroscience. 1984 Feb;11(2):473-86
references: 6717800
references: Exp Brain Res. 2010 Jun;203(2):271-83
references: 20379705
references: J Neurosci. 2011 Feb 9;31(6):1944-8
references: 21307232
references: Clin Neurophysiol. 2012 Jun;123(6):1216-25
references: 22364723
references: J Physiol. 2012 Aug 15;590(16):4011-27
references: 22641776
references: J Neurophysiol. 2012 Dec;108(11):3096-104
references: 22956793
references: J Neurosci. 2014 Feb 26;34(9):3350-63
references: 24573292
references: J Neurophysiol. 1999 Nov;82(5):2676-92
references: 10561437
references: J Neurosci Methods. 2000 Mar 15;96(2):153-60
references: 10720680
references: Nat Neurosci. 2001 Oct;4(10):1020-5
references: 11547338
references: J Physiol. 2002 Aug 15;543(Pt 1):289-96
references: 12181299
references: J Neurophysiol. 1985 Mar;53(3):786-804
references: 2984354
references: Exp Brain Res. 1974;21(1):19-44
references: 4422971
references: J Physiol. 1975 Apr;246(3):549-69
references: 1133787
references: Exp Brain Res. 1975 Oct 24;23(4):333-51
references: 1183508
references: Brain Res. 1976 Dec 3;117(3):529-33
references: 990943
references: J Comp Neurol. 1997 Jan 13;377(2):234-50
references: 8986883
references: Behav Brain Res. 1997 Sep;87(2):255-69
references: 9331494
references: Neuroimage. 1996 Oct;4(2):119-50
references: 9345504
references: J Neurosci Methods. 1998 Feb 20;79(2):143-50
references: 9543480
references: J Neurophysiol. 1998 Sep;80(3):1391-406
references: 9744948
references: J Neurophysiol. 1998 Oct;80(4):1961-80
references: 9772253
references: J Neurophysiol. 1999 Jan;81(1):319-33
references: 9914292
references: Science. 1999 Sep 24;285(5436):2136-9
references: 10497133
references: J Physiol. 1952 Aug;117(4):492-9
references: 12991236
references: Yale J Biol Med. 1952 Dec;25(3):176-201
references: 13015950
references: Am J Physiol. 1954 Jan;176(1):52-64
references: 13124495
references: J Anat. 1958 Apr;92(2):198-218
references: 13525235
references: Exp Brain Res. 2004 Dec;159(3):284-300
references: 15221165
references: Neuroscientist. 2006 Feb;12(1):67-79
references: 16394194
references: Exp Brain Res. 2006 Aug;173(1):25-39
references: 16506008
references: J Neurophysiol. 2006 Nov;96(5):2229-52
references: 16837662
references: J Neurosci. 2007 Jul 25;27(30):8053-8
references: 17652596
references: J Physiol. 2007 Sep 15;583(Pt 3):1145-54
references: 17656436
references: Annu Rev Neurosci. 2008;31:195-218
references: 18558853
references: J Neurophysiol. 2008 Oct;100(4):2235-53
references: 18632892
references: Eur J Appl Physiol. 2009 Jan;105(1):131-9
references: 18853177
references: J Neurosci. 2009 Apr 15;29(15):4993-9
references: 19369568
references: Neuroscience. 2009 Nov 10;163(4):1158-70
references: 19631726
references: Eur J Neurosci. 2003 Oct;18(8):2273-84
references: 14622188
references: Prog Brain Res. 2004;143:239-49
references: 14653169
references: Prog Brain Res. 2004;143:251-61
references: 14653170
references: J Neurophysiol. 2004 Jul;92(1):83-95
references: 15014106
references: J Neurophysiol. 2004 Oct;92(4):2217-38
references: 15175364
references: Experientia. 1966 Jun 15;22(6):390
references: 5961677
references: J Neurophysiol. 1968 Jan;31(1):14-27
references: 4966614
references: Acta Physiol Scand. 1968 Nov;74(3):274-84
references: 5708553
references: J Neurosci. 2003 Mar 1;23(5):1867-78
references: 12629191