title: Inhibition of contralateral premotor cortex delays visually guided reaching movements in men but not in women.
abstract: The premotor-parietal network for preparation of visually guided reaching demonstrates activity mainly contralateral to the reaching arm in men but bilaterally in women. These sex differences are most prominent in the dorsal premotor cortex (PMd); however, the functional implications of these differences remain unclear. Therefore, in the experiments described here, we used continuous theta burst stimulation (cTBS) to test hypotheses regarding the roles of PMd both contralateral and ipsilateral to the reaching arm in men and in women. Inhibitory cTBS of the ipsilateral PMd did not have a significant effect on reaction time in either men or women. However, cTBS of the contralateral PMd resulted in a slowed mean reaction time in men but not in women. Movement times were unaffected by stimulation applied to either hemisphere. These results suggest the presence of sex differences in processing within the left PMd during visually guided reaching movements using the right arm. Further, when taken together, the results suggest that ipsilateral PMd activity in women may not be functionally necessary for reaching movements. Rather, this ipsilateral activity may provide a protective redundancy that can compensate for decreased activity from the contralateral PMd. The observation of sex differences in reaction times but not in movement times following cTBS to the contralateral hemisphere suggests that these sex differences are more strongly associated with movement planning than with motor execution.
authors: Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada.
authors: Diana J
authors: DJ
authors: Gorbet
authors: W Richard
authors: WR
authors: Staines
references: Brain Lang. 2003 Jun;85(3):385-95
references: 12744950
references: Stroke. 1996 May;27(5):897-903
references: 8623110
references: Nat Rev Neurosci. 2006 Jun;7(6):477-84
references: 16688123
references: Neuroimage. 2007 Jul 1;36(3):691-9
references: 17499524
references: Neuropsychologia. 2000;38(10):1362-74
references: 10869579
references: Neuroimage. 2003 Nov;20 Suppl 1:S89-100
references: 14597301
references: Neuropsychologia. 2009 Oct;47(12):2427-35
references: 19383501
references: J Neurosci. 1993 Mar;13(3):952-80
references: 7680069
references: Cortex. 2009 Apr;45(4):473-82
references: 18400218
references: Cereb Cortex. 1995 Sep-Oct;5(5):410-28
references: 8547788
references: Clin Neurophysiol. 2007 May;118(5):1028-32
references: 17368094
references: Clin Neurophysiol. 2009 Jun;120(6):1195-203
references: 19410505
references: Neuropsychologia. 2002;40(7):808-16
references: 11900731
references: Neurology. 2000 Dec 26;55(12):1883-94
references: 11134389
references: Restor Neurol Neurosci. 2009;27(3):163-79
references: 19531872
references: Cereb Cortex. 2008 Dec;18(12):2920-31
references: 18440950
references: J Neurophysiol. 2002 Feb;87(2):1149-54
references: 11826082
references: Ann Neurol. 1995 Jun;37(6):723-32
references: 7778845
references: Neuroreport. 2005 May 31;16(8):795-8
references: 15891572
references: Neuropsychologia. 2006;44(13):2594-606
references: 16300804
references: Neuroreport. 2002 Oct 28;13(15):1929-32
references: 12395094
references: Science. 2000 Dec 1;290(5497):1782-6
references: 11099420
references: Neuropsychologia. 2000;38(3):304-12
references: 10678696
references: Int J Psychophysiol. 2008 Apr;68(1):41-50
references: 18295364
references: Trends Neurosci. 2002 Jun;25(6):307-12
references: 12086749
references: Brain Lang. 2006 Aug;98(2):150-8
references: 16716389
references: Neuron. 2005 Jan 20;45(2):201-6
references: 15664172
references: Brain. 1998 May;121 ( Pt 5):785-99
references: 9619185
references: Psychiatry Res. 2000 Feb 28;98(1):1-13
references: 10708922
references: Exp Brain Res. 2010 Jun;203(4):693-700
references: 20461362
references: Neuroimage. 2005 Nov 15;28(3):618-26
references: 16081303
references: Annu Rev Neurosci. 1997;20:25-42
references: 9056706
references: Proc Natl Acad Sci U S A. 1996 Feb 6;93(3):1249-53
references: 8577749
references: Biol Psychiatry. 2007 Oct 15;62(8):847-55
references: 17544382
references: Nature. 1995 Feb 16;373(6515):607-9
references: 7854416
references: Neuroreport. 2004 Feb 9;15(2):219-23
references: 15076740
references: J Cogn Neurosci. 2003 Jul 1;15(5):683-93
references: 12965042
references: J Neurophysiol. 2004 Jul;92(1):10-9
references: 15212434
references: Exp Brain Res. 1993;95(1):28-40
references: 8405252
references: Cereb Cortex. 2001 Jun;11(6):490-7
references: 11375910
references: J Neurol Neurosurg Psychiatry. 2004 Apr;75(4):637-9
references: 15026515
references: Clin Neurophysiol. 2009 Apr;120(4):796-801
references: 19231274
references: Int J Psychophysiol. 2009 Jan;71(1):43-9
references: 18755225
references: Brain Lang. 2000 Jul;73(3):456-65
references: 10860566
references: Clin Neurophysiol. 2006 Jan;117(1):26-32
references: 16337187
references: Neuroimage. 2003 Sep;20(1):512-9
references: 14527611
references: Cereb Cortex. 1996 Mar-Apr;6(2):102-19
references: 8670643
references: Eur J Neurosci. 2007 Feb;25(4):1228-39
references: 17331218
references: Brain Res Rev. 2009 Oct;61(2):49-59
references: 19406148
references: J Neurosci. 2006 Jul 12;26(28):7452-9
references: 16837593
references: Curr Opin Neurobiol. 1997 Dec;7(6):849-59
references: 9464979
references: Neuropsychologia. 1971 Mar;9(1):97-113
references: 5146491
references: Exp Brain Res. 2008 Jun;188(1):77-89
references: 18368398
references: Neuroimage. 2003 Jul;19(3):513-31
references: 12880784
references: Stroke. 2003 May;34(5):1114-9
references: 12690218
references: J Stroke Cerebrovasc Dis. 2007 Jan-Feb;16(1):34-9
references: 17689390
references: Exp Brain Res. 2010 May;202(3):633-46
references: 20135101
references: Neuropsychologia. 2002;40(13):2397-408
references: 12417468
references: J Neurophysiol. 2009 Jun;101(6):2872-7
references: 19339458
references: Cereb Cortex. 2001 Jun;11(6):513-27
references: 11375913
references: Neuroimage. 2000 May;11(5 Pt 1):532-40
references: 10806038
references: Nat Neurosci. 2000 Apr;3(4):404-8
references: 10725932
references: Neuroimage. 2001 Jul;14(1 Pt 2):S40-5
references: 11373131
references: Ann Emerg Med. 2002 Nov;40(5):453-60
references: 12399786
references: Neuron. 2005 Mar 3;45(5):801-14
references: 15748854
references: Neuroimage. 2000 May;11(5 Pt 1):554-63
references: 10806041
references: Exp Brain Res. 2005 Dec;167(3):414-21
references: 16047176
references: J Neurol Neurosurg Psychiatry. 2007 Aug;78(8):819-24
references: 17098842
references: Biol Psychiatry. 2001 Mar 1;49(5):460-3
references: 11274658