Detection of depression and facilitation of quantal electromyographic responses in man

Quantal EMG responses in human muscles and methods of evoking and recording them are described briefly. Techniques and statistical tests for the analysis of quantal H-reflexes are derived from probit analysis: to give a precise estimate of reflex threshold; to characterize the responding motoneurones; to assess threshold shift. With these techniques, the precision of the threshold estimate is usually better than +/- 2%. A probability profile and its associated cumulative sum chart are constructed from quantal response data to assess the latency and time course of conditioned changes in response probability. The application of these techniques is illustrated using recordings from recent experiments in man.