Skip to main content

Advertisement

SpringerLink
Log in

The Hand Motor Hotspot is not Always Located in the Hand Knob: A Neuronavigated Transcranial Magnetic Stimulation Study

  • Original Paper
  • Published:
Brain Topography Aims and scope Submit manuscript

Abstract

The hand motor hot spot (hMHS) is one of the most salient parameters in transcranial magnetic stimulation (TMS) practice, notably used for targeting. It is commonly accepted that the hMHS corresponds to the hand representation within the primary motor cortex (M1). Anatomical and imaging studies locate this representation in a region of the central sulcus called the “hand knob”. The aim of this study was to determine if the hMHS location corresponds to its expected location at the hand knob. Twelve healthy volunteers and eleven patients with chronic neuropathic pain of various origins, but not related to a brain lesion, were enrolled. Morphological magnetic resonance imaging of the brain was normal in all participants. Both hemispheres were studied in all participants except four (two patients and two healthy subjects). Cortical mapping of the hand motor area was conducted using a TMS-dedicated navigation system and recording motor evoked potentials (MEPs) in the contralateral first dorsal interosseous (FDI) muscle. We then determined the anatomical position of the hMHS, defined as the stimulation site providing the largest FDI-MEPs. In 45 % of hemispheres of normal subjects and 25 % of hemispheres of pain patients, the hMHS was located over the central sulcus, most frequently at the level of the hand knob. However, in the other cases, the hMHS was located outside M1, most frequently anteriorly over the precentral or middle frontal gyrus. This study shows that the hMHS does not always correspond to the hand knob and M1 location in healthy subjects or patients. Therefore, image-guided navigation is needed to improve the anatomical accuracy of TMS targeting, even for M1.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  • Ahdab R, Ayache SS, Brugières P et al (2010) Comparison of “standard” and “navigated” procedures of TMS coil positioning over motor, premotor and prefrontal targets in depressive patients. Neurophysiol Clin 40:27–36

    Article  CAS  PubMed  Google Scholar 

  • Ahdab R, Ayache SS, Farhat WH et al (2014) Reappraisal of the anatomical landmarks of motor and premotor cortical regions for image-guided brain navigation in TMS practice. Hum Brain Mapp 35:2435–2447

    Article  PubMed  Google Scholar 

  • Brodmann K (1909) Vergleichende Lokalisationslehre der Groβhirnrinde in ihren 883 Prinzipien dargestellt auf Grund des Zellaufbaues. Barth, Leipzig

    Google Scholar 

  • Classen J, Knorr U, Werhahn KJ et al (1998) Multimodal output mapping of human central motor representation on different spatial scales. J Physiol 512:163–179

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Danner N, Julkunen P, Könönen M, Säisänen L, Nurkkala J, Karhu J (2008) Navigated transcranial magnetic stimulation and computed electric field strength reduce stimulator-dependent differences in the motor threshold. J Neurosci Methods 174:116–122

    Article  PubMed  Google Scholar 

  • Deng ZD, Lisanby SH, Peterchev AV (2013) Electric field depth-focality tradeoff in transcranial magnetic stimulation: simulation comparison of 50 coil designs. Brain Stimul 6:1–13

    Article  PubMed  Google Scholar 

  • Denslow S, Bohning DE, Bohning PA et al (2005) An increased precision comparison of TMS-induced motor cortex BOLD fMRI response for image-guided versus function-guided coil placement. Cogn Behav Neurol 18:119–126

    Article  PubMed  Google Scholar 

  • Diekhoff S, Uludag K, Sparing R et al (2011) Functional localization in the human brain: gradient-echo, spin-echo, and arterial spin-labeling fMRI compared with neuronavigated TMS. Hum Brain Mapp 32:341–357

    Article  PubMed  Google Scholar 

  • Foerster O (1936) The motor cortex in man in the light of Hughlings Jackson’s doctrines. Brain 59:135–159

    Article  Google Scholar 

  • Geyer S, Matelli M, Luppino G, Zilles K (2000) Functional neuroanatomy of the primate isocortical motor system. Anat Embryol 202:443–474

    Article  CAS  PubMed  Google Scholar 

  • Ghosh S, Porter R (1988) Corticocortical synaptic influences on morphologically identified pyramidal neurones in the motor cortex of the monkey. J Physiol 400:617–629

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Godschalk M, Mitz AR, van Duin B, van der Burg H (1995) Somatotopy of monkey premotor cortex examined with microstimulation. Neurosci Res 23:269–279

    Article  CAS  PubMed  Google Scholar 

  • Grafton ST, Woods RP, Mazziotta JC, Phelps ME (1991) Somatotopic mapping of the primary motor cortex in humans: activation studies with cerebral blood flow and positron emission tomography. J Neurophysiol 66:735–743

    CAS  PubMed  Google Scholar 

  • Graziano MS, Taylor CS, Moore T (2002a) Complex movements evoked by microstimulation of precentral cortex. Neuron 34:841–851

    Article  CAS  PubMed  Google Scholar 

  • Graziano MS, Taylor CS, Moore T, Cooke DF (2002b) The cortical control of movement revisited. Neuron 36:349–362

    Article  CAS  PubMed  Google Scholar 

  • He SQ, Dum RP, Strick PL (1993) Topographic organization of corticospinal projections from the frontal lobe: motor areas on the lateral surface of the hemisphere. J Neurosci 13:952–980

    CAS  PubMed  Google Scholar 

  • He SQ, Dum RP, Strick PL (1995) Topographic organization of corticospinal projections from the frontal lobe: motor areas on the medial surface of the hemisphere. J Neurosci 15:3284–3306

    CAS  PubMed  Google Scholar 

  • Inuggi A, Filippi M, Chieffo R et al (2010) Motor area localization using fMRI-constrained cortical current density reconstruction of movement-related cortical potentials, a comparison with fMRI and TMS mapping. Brain Res 1308:68–78

    Article  CAS  PubMed  Google Scholar 

  • Julkunen P, Ruohonen J, Sääskilahti S et al (2011) Threshold curves for transcranial magnetic stimulation to improve reliability of motor pathway status assessment. Clin Neurophysiol 122:975–983

    Article  PubMed  Google Scholar 

  • Kahn T, Schwabe B, Bettag M et al (1996) Mapping of the cortical motor hand area with functional MR imaging and MR imaging-guided laser-induced interstitial thermotherapy of brain tumors. Radiology 200:149–157

    Article  CAS  PubMed  Google Scholar 

  • Kantelhardt SR, Fadini T, Finke M et al (2010) Robot-assisted image-guided transcranial magnetic stimulation for somatotopic mapping of the motor cortex: a clinical pilot study. Acta Neurochir 152:333–343

    Article  PubMed  Google Scholar 

  • Kraus D, Gharabaghi A (2015) Projecting navigated TMS sites on the gyral anatomy decreases inter-subject variability of cortical motor maps. Brain Stimul. doi:10.1016/j.brs.2015.03.006

    PubMed  Google Scholar 

  • Lefaucheur JP (2010) Why image-guided navigation becomes essential in the practice of transcranial magnetic stimulation. Neurophysiol Clin 40:1–5

    Article  PubMed  Google Scholar 

  • Lefaucheur JP, André-Obadia N, Antal A et al (2014) Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS). Clin Neurophysiol 125:2150–2206

    Article  PubMed  Google Scholar 

  • Lotze M, Kaethner RJ, Erb M et al (2003) Comparison of representational maps using functional magnetic resonance imaging and transcranial magnetic stimulation. Clin Neurophysiol 114:306–312

    Article  CAS  PubMed  Google Scholar 

  • Maier MA, Armand J, Kirkwood PA et al (2002) Differences in the corticospinal projection from primary motor cortex and supplementary motor area to macaque upper limb motoneurons: an anatomical and electrophysiological study. Cereb Cortex 12:281–296

    Article  CAS  PubMed  Google Scholar 

  • Meincke J, Hewitt M, Batsikadze G, Liebetanz D (2016) Automated TMS hotspot-hunting using a closed loop threshold-based algorithm. Neuroimage 124:509–517

    Article  PubMed  Google Scholar 

  • Mylius V, Ayache SS, Ahdab R et al (2013) Definition of DLPFC and M1 according to anatomical landmarks for navigated brain stimulation: inter-rater reliability, accuracy, and influence of gender and age. Neuroimage 78:224–232

    Article  CAS  PubMed  Google Scholar 

  • Nii Y, Uematsu S, Lesser RP, Gordon B (1996) Does the central sulcus divide motor and sensory functions? Cortical mapping of human hand areas as revealed by electrical stimulation through subdural grid electrodes. Neurology 46:360–367

    Article  CAS  PubMed  Google Scholar 

  • Niskanen E, Julkunen P, Säisänen L, Vanninen R, Karjalainen P, Könönen M (2010) Group-level variations in motor representation areas of thenar and anterior tibial muscles: navigated Transcranial Magnetic Stimulation Study. Hum Brain Mapp 31:1272–1280

    PubMed  Google Scholar 

  • Nummenmaa A, Stenroos M, Ilmoniemi RJ et al (2013) Comparison of spherical and realistically shaped boundary element head models for transcranial magnetic stimulation navigation. Clin Neurophysiol 124:1995–2007

    Article  PubMed  PubMed Central  Google Scholar 

  • Opitz A, Legon W, Rowlands A et al (2013) Physiological observations validate finite element models for estimating subject-specific electric field distributions induced by transcranial magnetic stimulation of the human motor cortex. Neuroimage 81:253–264

    Article  PubMed  Google Scholar 

  • Penfield W, Boldrey E (1937) Somatic motor and sensory representation in the cerebral cortex of man as studied by electrical stimulation. Brain 60:389–443

    Article  Google Scholar 

  • Picht T, Mularski S, Kuehn B et al (2009) Navigated transcranial magnetic stimulation for preoperative functional diagnostics in brain tumor surgery. Neurosurgery 65:93–99

    Article  PubMed  Google Scholar 

  • Picht T, Schmidt S, Brandt S et al (2011) Preoperative functional mapping for rolandic brain tumor surgery: comparison of navigated transcranial magnetic stimulation to direct cortical stimulation. Neurosurgery 69:581–588

    Article  PubMed  Google Scholar 

  • Puce A, Constable RT, Luby ML et al (1995) Functional magnetic resonance imaging of sensory and motor cortex: comparison with electrophysiological localization. J Neurosurg 83:262–270

    Article  CAS  PubMed  Google Scholar 

  • Rademacher J, Burgel U, Geyer S et al (2001) Variability and asymmetry in the human precentral motor system. A cytoarchitectonic and myeloarchitectonic brain mapping study. Brain 124:2232–2258

    Article  CAS  PubMed  Google Scholar 

  • Rossini PM, Burke D, Chen R et al (2015) Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: basic principles and procedures for routine clinical and research application. An updated report from an I.F.C.N Committee. Clin Neurophysiol 126:1071–1107

    Article  CAS  PubMed  Google Scholar 

  • Rumeau C, Tzourio N, Murayama N et al (1994) Location of hand function in the sensorimotor cortex: MR and functional correlation. AJNR Am J Neuroradiol 15:567–572

    CAS  PubMed  Google Scholar 

  • Ruohonen J, Karhu J (2010) Navigated transcranial magnetic stimulation. Neurophysiol Clin 40:7–17

    Article  CAS  PubMed  Google Scholar 

  • Schmidt S, Bathe-Peters R, Fleischmann R, Rönnefarth M, Scholz M, Brandt SA (2015) Nonphysiological factors in navigated TMS studies; confounding covariates and valid intracortical estimates. Hum Brain Mapp 36:40–49

    Article  PubMed  Google Scholar 

  • Shimazu H, Maier MA, Cerri G et al (2004) Macaque ventral premotor cortex exerts powerful facilitation of motor cortex outputs to upper limb motoneurons. J Neurosci 24:1200–1211

    Article  CAS  PubMed  Google Scholar 

  • Sparing R, Buelte D, Meister IG et al (2008) Transcranial magnetic stimulation and the challenge of coil placement: a comparison of conventional and stereotaxic neuronavigational strategies. Hum Brain Mapp 29:82–96

    Article  PubMed  Google Scholar 

  • Tarapore PE, Tate MC, Findlay AM et al (2012) Preoperative multimodal motor mapping: a comparison of magnetoencephalography imaging, navigated transcranial magnetic stimulation, and direct cortical stimulation. J Neurosurg 117:354–362

    Article  PubMed  PubMed Central  Google Scholar 

  • Teitti S, Määttä S, Säisänen L et al (2008) Non-primary motor areas in the human frontal lobe are connected directly to hand muscles. Neuroimage 40:1243–1250

    Article  CAS  PubMed  Google Scholar 

  • Terao Y, Ugawa Y, Sakai K et al (1998) Localizing the site of magnetic brain stimulation by functional MRI. Exp Brain Res 121:145–152

    Article  CAS  PubMed  Google Scholar 

  • Thielscher A, Kammer T (2004) Electric field properties of two commercial figure-8 coils in TMS: calculation of focality and efficiency. Clin Neurophysiol 115:1697–1708

    Article  PubMed  Google Scholar 

  • Tokuno H, Nambu A (2000) Organization of nonprimary motor cortical inputs on pyramidal and nonpyramidal tract neurons of primary motor cortex: an electrophysiological study in the macaque monkey. Cereb Cortex 10:58–68

    Article  CAS  PubMed  Google Scholar 

  • Uematsu S, Lesser R, Fisher RS et al (1992) Motor and sensory cortex in humans: topography studied with chronic subdural stimulation. Neurosurgery 31:59–71

    Article  CAS  PubMed  Google Scholar 

  • Wassermann EM, Wang B, Zeffiro TA et al (1996) Locating the motor cortex on the MRI with transcranial magnetic stimulation and PET. Neuroimage 3:1–9

    Article  CAS  PubMed  Google Scholar 

  • Yousry TA, Schmid UD, Jassoy AG et al (1995) Topography of the cortical motor hand area: prospective study with functional MR imaging and direct motor mapping at surgery. Radiology 195:23–29

    Article  CAS  PubMed  Google Scholar 

  • Yousry TA, Schmid UD, Alkadhi H et al (1997) Localization of the motor hand area to a knob on the precentral gyrus: a new landmark. Brain 120:141–157

    Article  PubMed  Google Scholar 

Download references

Author information

Author notes

    Authors and Affiliations

    1. EA 4391, Excitabilité Nerveuse et Thérapeutique, Université Paris-Est-Créteil, Créteil, France

      Rechdi Ahdab, Samar S. Ayache, Wassim H. Farhat & Jean-Pascal Lefaucheur

    2. Service de Physiologie – Explorations Fonctionnelles, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, 51 avenue de Lattre de Tassigny, 94010, Créteil, France

      Rechdi Ahdab, Samar S. Ayache, Wassim H. Farhat & Jean-Pascal Lefaucheur

    3. Neurology Division, University Medical Center Rizk Hospital, Beirut, Lebanon

      Rechdi Ahdab & Samar S. Ayache

    4. Service de Neuroradiologie, Hôpital Henri Mondor, Assistance Publique – Hôpitaux de Paris, Créteil, France

      Pierre Brugières

    Authors
    1. Rechdi Ahdab
      View author publications

      You can also search for this author in PubMed Google Scholar

    2. Samar S. Ayache
      View author publications

      You can also search for this author in PubMed Google Scholar

    3. Pierre Brugières
      View author publications

      You can also search for this author in PubMed Google Scholar

    4. Wassim H. Farhat
      View author publications

      You can also search for this author in PubMed Google Scholar

    5. Jean-Pascal Lefaucheur
      View author publications

      You can also search for this author in PubMed Google Scholar

    Corresponding author

    Correspondence to Samar S. Ayache.

    Additional information

    Rechdi Ahdab and Samar S. Ayache have contributed equally to this work.

    Rights and permissions

    Reprints and permissions

    About this article

    Check for updates. Verify currency and authenticity via CrossMark

    Cite this article

    Ahdab, R., Ayache, S.S., Brugières, P. et al. The Hand Motor Hotspot is not Always Located in the Hand Knob: A Neuronavigated Transcranial Magnetic Stimulation Study. Brain Topogr 29, 590–597 (2016). https://doi.org/10.1007/s10548-016-0486-2

    Download citation

    • Received:

    • Accepted:

    • Published:

    • Issue Date:

    • DOI: https://doi.org/10.1007/s10548-016-0486-2

    Keywords

    Search

    Navigation