[A comparison of statistical methods for quantal analysis in computer and physiological experiments]

Amplitude distributions of postsynaptic potentials were simulated in computer experiments on the basis of binomial statistics. Influences of the sample size (N) and noise standard deviation (Sn) on the determination of the quantal content (m) and quantal size (v) were studied. Four methods of the quantal parameter estimation were modified and used: histogram, variance, failure and combined method. Three last methods gave satisfactory estimations (within +/- 10%) at N = 500-1000 and Sn less than 2v. The histogram method was adequate at Sn less than or equal to v. Similar results were obtained at N = 50-200, when the experiment was repeated about ten times. Applicability of similar methods was confirmed by the analysis of an intracellular record of inhibitory postsynaptic potentials (N = 1333) from the sensorimotor cortex of rabbit.