Deciphering the contribution of intrinsic and synaptic currents to the effects of transient synaptic inputs on human motor unit discharge

Powers R. K., Türker K. S.

Clinical Neurophysiology, cilt.121, sa.10, ss.1643-1654, 2010 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Derleme
  • Cilt numarası: 121 Sayı: 10
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1016/j.clinph.2009.10.041
  • Dergi Adı: Clinical Neurophysiology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1643-1654
  • Anahtar Kelimeler: Motor unit, Motoneuron, Synaptic potentials, Peri-stimulus time histogram (PSTH), Peri-stimulus time frequencygram (PSF)
  • İstanbul Gelişim Üniversitesi Adresli: Hayır

Özet

The amplitude and time course of synaptic potentials in human motoneurons can be estimated in tonically discharging motor units by measuring stimulus-evoked changes in the rate and probability of motor unit action potentials. However, in spite of the fact that some of these techniques have been used for over 30 years, there is still no consensus on the best way to estimate the characteristics of synaptic potentials or on the accuracy of these estimates. In this review, we compare different techniques for estimating synaptic potentials from human motor unit discharge and also discuss relevant animal models in which estimated synaptic potentials can be compared to those directly measured from intracellular recordings. We also review the experimental evidence on how synaptic noise and intrinsic motoneuron properties influence their responses to synaptic inputs. Finally, we consider to what extent recordings of single motor unit discharge in humans can be used to distinguish the contribution of changes in synaptic inputs versus changes in intrinsic motoneuron properties to altered motoneuron responses following CNS injury. © 2010.