The new technique for accurate estimation of the spinal cord circuitry: recording reflex responses of large motor unit populations

Utku S. Yavuz, Francesco Negro, Oguz Sebik, Ales Holobar, Cornelius Froemmel, Kemal S. Turker, Dario Farina

    Research output: Contribution to journalMeeting AbstractAcademic

    Abstract

    We propose and validate a non-invasive method that enables accurate detection of the discharge times of a relatively large number of motor units during excitatory and inhibitory reflex stimulations. HDsEMG and intramuscular EMG (iEMG) were recorded from the tibialis anterior muscle during ankle dorsiflexions performed at 5%, 10%, and 20% of the maximum voluntary contraction (MVC) force, in 9 healthy subjects. The tibial nerve (inhibitory reflex) and the peroneal nerve (excitatory reflex) were stimulated with constant current stimuli. In total, 416 motor units were identified from the automatic decomposition of the HDsEMG. The iEMG was decomposed using a state-of-the-art decomposition tool and provided 84 motor units (average of two recording sites). The reflex responses of the detected motor units were analyzed using the peri-stimulus time histogram (PSTH) and the peri-stimulus frequencygram (PSF). The reflex responses of the common motor units identified concurrently from the HDsEMG and the iEMG signals showed an average disagreement (the difference between number of observed spikes in each bin relative to the mean) of 8.2±2.2% (5% MVC), 6.8±1.0% (10% MVC), and 7.5±2.2% (20% MVC), for reflex inhibition, and 6.5±4.1%, 12.0±1.8%, 13.9±2.4%, for reflex excitation. There was no significant difference between the characteristics of the reflex responses, such as latency, amplitude and duration, for the motor units identified by both techniques. Finally, reflex responses could be identified at higher force (four of the nine subjects performed contraction up to 50% MVC) using HDsEMG but not iEMG, because of the difficulty in decomposing the iEMG at high forces. In conclusion, single motor unit reflex responses can be estimated accurately and non-invasively in relatively large populations of motor units using HDsEMG. This non-invasive approach may enable a more thorough investigation of the synaptic input distribution on active motor units at various force levels.
    Original languageEnglish
    Article numberS9-3
    Pages (from-to)37-38
    Number of pages2
    JournalActa physiologica
    Volume215
    Publication statusPublished - Nov 2015
    EventJoint Meeting of the Federation of European Physiological Societies and the Baltic Physiological Societies 2015 - Kaunas, Lithuania
    Duration: 26 Aug 201529 Aug 2015
    http://www.feps2015.org/

    Cite this

    Yavuz, U. S., Negro, F., Sebik, O., Holobar, A., Froemmel, C., Turker, K. S., & Farina, D. (2015). The new technique for accurate estimation of the spinal cord circuitry: recording reflex responses of large motor unit populations. Acta physiologica, 215, 37-38. [S9-3].
    Yavuz, Utku S. ; Negro, Francesco ; Sebik, Oguz ; Holobar, Ales ; Froemmel, Cornelius ; Turker, Kemal S. ; Farina, Dario. / The new technique for accurate estimation of the spinal cord circuitry : recording reflex responses of large motor unit populations. In: Acta physiologica. 2015 ; Vol. 215. pp. 37-38.
    @article{d3508aa220c2461482596d6120abfc30,
    title = "The new technique for accurate estimation of the spinal cord circuitry: recording reflex responses of large motor unit populations",
    abstract = "We propose and validate a non-invasive method that enables accurate detection of the discharge times of a relatively large number of motor units during excitatory and inhibitory reflex stimulations. HDsEMG and intramuscular EMG (iEMG) were recorded from the tibialis anterior muscle during ankle dorsiflexions performed at 5{\%}, 10{\%}, and 20{\%} of the maximum voluntary contraction (MVC) force, in 9 healthy subjects. The tibial nerve (inhibitory reflex) and the peroneal nerve (excitatory reflex) were stimulated with constant current stimuli. In total, 416 motor units were identified from the automatic decomposition of the HDsEMG. The iEMG was decomposed using a state-of-the-art decomposition tool and provided 84 motor units (average of two recording sites). The reflex responses of the detected motor units were analyzed using the peri-stimulus time histogram (PSTH) and the peri-stimulus frequencygram (PSF). The reflex responses of the common motor units identified concurrently from the HDsEMG and the iEMG signals showed an average disagreement (the difference between number of observed spikes in each bin relative to the mean) of 8.2±2.2{\%} (5{\%} MVC), 6.8±1.0{\%} (10{\%} MVC), and 7.5±2.2{\%} (20{\%} MVC), for reflex inhibition, and 6.5±4.1{\%}, 12.0±1.8{\%}, 13.9±2.4{\%}, for reflex excitation. There was no significant difference between the characteristics of the reflex responses, such as latency, amplitude and duration, for the motor units identified by both techniques. Finally, reflex responses could be identified at higher force (four of the nine subjects performed contraction up to 50{\%} MVC) using HDsEMG but not iEMG, because of the difficulty in decomposing the iEMG at high forces. In conclusion, single motor unit reflex responses can be estimated accurately and non-invasively in relatively large populations of motor units using HDsEMG. This non-invasive approach may enable a more thorough investigation of the synaptic input distribution on active motor units at various force levels.",
    author = "Yavuz, {Utku S.} and Francesco Negro and Oguz Sebik and Ales Holobar and Cornelius Froemmel and Turker, {Kemal S.} and Dario Farina",
    year = "2015",
    month = "11",
    language = "English",
    volume = "215",
    pages = "37--38",
    journal = "Acta physiologica",
    issn = "1748-1708",
    publisher = "Wiley-Blackwell",

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    Yavuz, US, Negro, F, Sebik, O, Holobar, A, Froemmel, C, Turker, KS & Farina, D 2015, 'The new technique for accurate estimation of the spinal cord circuitry: recording reflex responses of large motor unit populations', Acta physiologica, vol. 215, S9-3, pp. 37-38.

    The new technique for accurate estimation of the spinal cord circuitry : recording reflex responses of large motor unit populations. / Yavuz, Utku S.; Negro, Francesco; Sebik, Oguz; Holobar, Ales; Froemmel, Cornelius; Turker, Kemal S.; Farina, Dario.

    In: Acta physiologica, Vol. 215, S9-3, 11.2015, p. 37-38.

    Research output: Contribution to journalMeeting AbstractAcademic

    TY - JOUR

    T1 - The new technique for accurate estimation of the spinal cord circuitry

    T2 - recording reflex responses of large motor unit populations

    AU - Yavuz, Utku S.

    AU - Negro, Francesco

    AU - Sebik, Oguz

    AU - Holobar, Ales

    AU - Froemmel, Cornelius

    AU - Turker, Kemal S.

    AU - Farina, Dario

    PY - 2015/11

    Y1 - 2015/11

    N2 - We propose and validate a non-invasive method that enables accurate detection of the discharge times of a relatively large number of motor units during excitatory and inhibitory reflex stimulations. HDsEMG and intramuscular EMG (iEMG) were recorded from the tibialis anterior muscle during ankle dorsiflexions performed at 5%, 10%, and 20% of the maximum voluntary contraction (MVC) force, in 9 healthy subjects. The tibial nerve (inhibitory reflex) and the peroneal nerve (excitatory reflex) were stimulated with constant current stimuli. In total, 416 motor units were identified from the automatic decomposition of the HDsEMG. The iEMG was decomposed using a state-of-the-art decomposition tool and provided 84 motor units (average of two recording sites). The reflex responses of the detected motor units were analyzed using the peri-stimulus time histogram (PSTH) and the peri-stimulus frequencygram (PSF). The reflex responses of the common motor units identified concurrently from the HDsEMG and the iEMG signals showed an average disagreement (the difference between number of observed spikes in each bin relative to the mean) of 8.2±2.2% (5% MVC), 6.8±1.0% (10% MVC), and 7.5±2.2% (20% MVC), for reflex inhibition, and 6.5±4.1%, 12.0±1.8%, 13.9±2.4%, for reflex excitation. There was no significant difference between the characteristics of the reflex responses, such as latency, amplitude and duration, for the motor units identified by both techniques. Finally, reflex responses could be identified at higher force (four of the nine subjects performed contraction up to 50% MVC) using HDsEMG but not iEMG, because of the difficulty in decomposing the iEMG at high forces. In conclusion, single motor unit reflex responses can be estimated accurately and non-invasively in relatively large populations of motor units using HDsEMG. This non-invasive approach may enable a more thorough investigation of the synaptic input distribution on active motor units at various force levels.

    AB - We propose and validate a non-invasive method that enables accurate detection of the discharge times of a relatively large number of motor units during excitatory and inhibitory reflex stimulations. HDsEMG and intramuscular EMG (iEMG) were recorded from the tibialis anterior muscle during ankle dorsiflexions performed at 5%, 10%, and 20% of the maximum voluntary contraction (MVC) force, in 9 healthy subjects. The tibial nerve (inhibitory reflex) and the peroneal nerve (excitatory reflex) were stimulated with constant current stimuli. In total, 416 motor units were identified from the automatic decomposition of the HDsEMG. The iEMG was decomposed using a state-of-the-art decomposition tool and provided 84 motor units (average of two recording sites). The reflex responses of the detected motor units were analyzed using the peri-stimulus time histogram (PSTH) and the peri-stimulus frequencygram (PSF). The reflex responses of the common motor units identified concurrently from the HDsEMG and the iEMG signals showed an average disagreement (the difference between number of observed spikes in each bin relative to the mean) of 8.2±2.2% (5% MVC), 6.8±1.0% (10% MVC), and 7.5±2.2% (20% MVC), for reflex inhibition, and 6.5±4.1%, 12.0±1.8%, 13.9±2.4%, for reflex excitation. There was no significant difference between the characteristics of the reflex responses, such as latency, amplitude and duration, for the motor units identified by both techniques. Finally, reflex responses could be identified at higher force (four of the nine subjects performed contraction up to 50% MVC) using HDsEMG but not iEMG, because of the difficulty in decomposing the iEMG at high forces. In conclusion, single motor unit reflex responses can be estimated accurately and non-invasively in relatively large populations of motor units using HDsEMG. This non-invasive approach may enable a more thorough investigation of the synaptic input distribution on active motor units at various force levels.

    M3 - Meeting Abstract

    VL - 215

    SP - 37

    EP - 38

    JO - Acta physiologica

    JF - Acta physiologica

    SN - 1748-1708

    M1 - S9-3

    ER -