ESTIMATING POSTSYNAPTIC POTENTIALS IN TONICALLY DISCHARGING HUMAN MOTONEURONS

The activity of single motor units in human muscles can be recorded wi th relative ease, and the spike train of a single motor unit precisely reflects the spike train of the parent motoneurone. This has led to t he proposal of a number of methods to estimate stimulus-evoked post-sy naptic potentials in human motoneurones. All of these methods rely on manipulating the spike trains of motor units over a number of trials. All are based on a number of assumptions, all have limitations, and no ne so far have passed the test of a direct comparison of the estimate of the shape of the post-synaptic potential with a direct intracellula r measurement of it. These techniques are summarised in this review. ( C) 1997 Elsevier Science B.V.