Cortical excitability differences in hand muscles follow a split‐hand pattern in healthy controls

Introduction: Differences in cortical and axonal excitability may underlie preferential atrophy of abductor pollicis brevis (APB) and first dorsal interosseous (FDI) in amyotrophic lateral sclerosis, termed the split‐hand. Consequently, this study aimed to determine whether differences in excitability follow a split‐hand pattern across the intrinsic hand muscles. Methods: Excitability studies were undertaken using threshold tracking techniques in 26 healthy controls with responses recorded over APB, FDI, and abductor digiti minimi. Results: Short interval intracortical inhibition was significantly greater from the APB and FDI. In addition, motor evoked potential amplitude was greater, while cortical silent period was longer from APB and FDI. At a peripheral level, the strength‐duration time constant was greater when recorded over APB. Conclusions: This study establishes that differences in cortical excitability follow the split‐hand pattern in healthy controls, a finding potentially explained by evolution of specialized activity of APB/FDI in complex hand tasks. Muscle Nerve 49: 836–844, 2014

[1]  C. Yiannikas,et al.  Split-hand index for the diagnosis of amyotrophic lateral sclerosis , 2013, Clinical Neurophysiology.

[2]  Markus Kofler,et al.  Differential effect of baclofen on cortical and spinal inhibitory circuits , 2013, Clinical Neurophysiology.

[3]  Mark Hallett,et al.  Transcranial magnetic stimulation and amyotrophic lateral sclerosis: pathophysiological insights , 2012, Journal of Neurology, Neurosurgery & Psychiatry.

[4]  T L Chenevert,et al.  Decreased motor cortex γ-aminobutyric acid in amyotrophic lateral sclerosis , 2012, Neurology.

[5]  K. Quinlan Links between electrophysiological and molecular pathology of amyotrophic lateral sclerosis. , 2011, Integrative and comparative biology.

[6]  M. Kiernan,et al.  Appearance, phenomenology and diagnostic utility of the split hand in amyotrophic lateral sclerosis , 2011 .

[7]  A. Eisen,et al.  The split hand syndrome in amyotrophic lateral sclerosis , 2011, Journal of Neurology, Neurosurgery & Psychiatry.

[8]  O. Hardiman,et al.  Amyotrophic lateral sclerosis , 2011, The Lancet.

[9]  J. Karhu,et al.  Short- and intermediate-interval cortical inhibition and facilitation assessed by navigated transcranial magnetic stimulation , 2011, Journal of Neuroscience Methods.

[10]  Alexander Kraskov,et al.  Corticospinal Neurons in Macaque Ventral Premotor Cortex with Mirror Properties: A Potential Mechanism for Action Suppression? , 2009, Neuron.

[11]  Tamara J. Dartnall,et al.  Corticomotor plasticity and learning of a ballistic thumb training task are diminished in older adults. , 2009, Journal of applied physiology.

[12]  David Burke,et al.  The effects of alterations in conditioning stimulus intensity on short interval intracortical inhibition , 2009, Brain Research.

[13]  Michel Dib,et al.  Biomarkers in Amyotrophic Lateral Sclerosis , 2009, Molecular Diagnosis & Therapy.

[14]  S. Kuwabara,et al.  Differences in excitability properties of FDI and ADM motor axons , 2009, Muscle & nerve.

[15]  M. Kiernan,et al.  Cortical hyperexcitability may precede the onset of familial amyotrophic lateral sclerosis. , 2008, Brain : a journal of neurology.

[16]  Toshio Shimizu,et al.  Dissociated small hand muscle atrophy in amyotrophic lateral sclerosis: Frequency, extent, and specificity , 2008, Muscle & nerve.

[17]  Robert Chen,et al.  The clinical diagnostic utility of transcranial magnetic stimulation: Report of an IFCN committee , 2008, Clinical Neurophysiology.

[18]  M. Kiernan,et al.  Novel threshold tracking techniques suggest that cortical hyperexcitability is an early feature of motor neuron disease. , 2006, Brain : a journal of neurology.

[19]  Matthew C Kiernan,et al.  Assessment of cortical excitability using threshold tracking techniques , 2006, Muscle & nerve.

[20]  Paul Sacco,et al.  Short-interval cortical inhibition and corticomotor excitability with fatiguing hand exercise: a central adaptation to fatigue? , 2006, Experimental Brain Research.

[21]  R. Lemon,et al.  Comparing the function of the corticospinal system in different species: Organizational differences for motor specialization? , 2005, Muscle & nerve.

[22]  Peter K. Stys,et al.  General mechanisms of axonal damage and its prevention , 2005, Journal of the Neurological Sciences.

[23]  M. Ridding,et al.  Modulation of intracortical excitability in human hand motor areas. The effect of cutaneous stimulation and its topographical arrangement , 2005, Experimental Brain Research.

[24]  T Brochier,et al.  Patterns of muscle activity underlying object-specific grasp by the macaque monkey. , 2004, Journal of neurophysiology.

[25]  J. Rothwell,et al.  The cortical silent period: intrinsic variability and relation to the waveform of the transcranial magnetic stimulation pulse , 2004, Clinical Neurophysiology.

[26]  John C Rothwell,et al.  Differential effect of muscle vibration on intracortical inhibitory circuits in humans , 2003, The Journal of physiology.

[27]  Ichiro Kanazawa,et al.  Further evidence to support different mechanisms underlying intracortical inhibition of the motor cortex , 2003, Experimental Brain Research.

[28]  H. Bostock,et al.  Two phases of intracortical inhibition revealed by transcranial magnetic threshold tracking , 2002, Experimental Brain Research.

[29]  J. Holstege,et al.  CuZn superoxide dismutase (SOD1) accumulates in vacuolated mitochondria in transgenic mice expressing amyotrophic lateral sclerosis-linked SOD1 mutations , 2001, Acta Neuropathologica.

[30]  D. Burke,et al.  Excitability of human axons , 2001, Clinical Neurophysiology.

[31]  F J Valero-Cuevas,et al.  Activation patterns of the thumb muscles during stable and unstable pinch tasks. , 2001, The Journal of hand surgery.

[32]  N. Murray,et al.  Clinical evaluation of excitability measures in sensory nerve , 2001, Muscle & nerve.

[33]  A. Eisen,et al.  The split hand in ALS has a cortical basis , 2000, Journal of the Neurological Sciences.

[34]  J. Rothwell,et al.  Direct demonstration of the effect of lorazepam on the excitability of the human motor cortex , 2000, Clinical Neurophysiology.

[35]  D. Burke,et al.  Multiple measures of axonal excitability: A new approach in clinical testing , 2000, Muscle & nerve.

[36]  A. Wilbourn,et al.  The “split hand syndrome” , 2000, Muscle & nerve.

[37]  P. Ashby,et al.  Mechanism of the silent period following transcranial magnetic stimulation Evidence from epidural recordings , 1999, Experimental Brain Research.

[38]  P J Delwaide,et al.  Corticomotoneuronal synaptic connections in normal man: an electrophysiological study. , 1999, Brain : a journal of neurology.

[39]  K J Werhahn,et al.  Differential effects on motorcortical inhibition induced by blockade of GABA uptake in humans , 1999, The Journal of physiology.

[40]  M. Schieppati,et al.  Comparison of intracortical inhibition and facilitation in distal and proximal arm muscles in humans , 1999, The Journal of physiology.

[41]  J C Rothwell,et al.  Comparison of descending volleys evoked by transcranial magnetic and electric stimulation in conscious humans. , 1998, Electroencephalography and clinical neurophysiology.

[42]  B Conrad,et al.  Continuous intrathecal baclofen infusions induced a marked increase of the transcranially evoked silent period in a patient with generalized dystonia , 1998, Muscle & nerve.

[43]  K. Sakai,et al.  Paired‐pulse magnetic stimulation of the human motor cortex: differences among I waves , 1998, The Journal of physiology.

[44]  R. L. Linscheid,et al.  EMG study of hand muscle recruitment during hard hammer percussion manufacture of Oldowan tools. , 1998, American journal of physical anthropology.

[45]  D. Burke,et al.  Threshold tracking techniques in the study of human peripheral nerve , 1998, Muscle & nerve.

[46]  Roger N. Lemon,et al.  REVIEW ■ : Mechanisms of Cortical Control of Hand Function , 1997 .

[47]  Rn Lemon,et al.  Mechanisms of cortical control of hand function , 1997 .

[48]  H. Tsuji,et al.  Intracortical facilitation and inhibition after transcranial magnetic stimulation in conscious humans. , 1997, The Journal of physiology.

[49]  D Burke,et al.  Strength-duration properties of human peripheral nerve. , 1996, Brain : a journal of neurology.

[50]  C. Marsden,et al.  Corticocortical inhibition in human motor cortex. , 1993, The Journal of physiology.

[51]  A Berardelli,et al.  Silent period evoked by transcranial stimulation of the human cortex and cervicomedullary junction. , 1993, The Journal of physiology.

[52]  R N Lemon,et al.  Task dependence of responses in first dorsal interosseous muscle to magnetic brain stimulation in man. , 1993, The Journal of physiology.

[53]  R. Mutani,et al.  Magnetic brain stimulation: the silent period after the motor evoked potential. , 1992, Neurology.

[54]  B. Pant,et al.  Amyotrophic lateral sclerosis (ALS): A phylogenetic disease of the corticomotoneuron? , 1992, Muscle & nerve.

[55]  M. Jeannerod The formation of finger grip during prehension. A cortically mediated visuomotor pattern , 1986, Behavioural Brain Research.

[56]  H Bostock,et al.  The strength‐duration relationship for excitation of myelinated nerve: computed dependence on membrane parameters. , 1983, The Journal of physiology.

[57]  C. Long,et al.  Intrinsic-extrinsic muscle control of the hand in power grip and precision handling. An electromyographic study. , 1970, The Journal of bone and joint surgery. American volume.

[58]  J. Napier The prehensile movements of the human hand. , 1956, The Journal of bone and joint surgery. British volume.

[59]  A. Ludolph,et al.  Amyotrophic lateral sclerosis. , 2012, Current opinion in neurology.

[60]  W. Bradley,et al.  Mitochondrial involvement in amyotrophic lateral sclerosis , 2007, Molecular Neurobiology.

[61]  U. Ziemann Cortical threshold and excitability measurements , 2004 .

[62]  R. Johansson,et al.  Development of human precision grip I: Basic coordination of force , 2004, Experimental Brain Research.

[63]  R. Johansson,et al.  Development of human precision grip , 2004, Experimental Brain Research.

[64]  M. Hepp-Reymond,et al.  EMG activation patterns during force production in precision grip , 2004, Experimental Brain Research.

[65]  Andrew Eisen,et al.  Clinical neurophysiology of motor neuron diseases , 2004 .

[66]  Robert Chen,et al.  Interactions between inhibitory and excitatory circuits in the human motor cortex , 2003, Experimental Brain Research.

[67]  J. Rothwell,et al.  Direct recordings of descending volleys after transcranial magnetic and electric motor cortex stimulation in conscious humans. , 1999, Electroencephalography and clinical neurophysiology. Supplement.

[68]  M W Marzke,et al.  Precision grips, hand morphology, and tools. , 1997, American journal of physical anthropology.

[69]  J. Rothwell,et al.  Latent addition in motor and sensory fibres of human peripheral nerve. , 1997, The Journal of physiology.

[70]  G. Weiss Sur la possibilite de rendre comparables entre eux les appareils servant a l'excitation electrique. , 1990 .