The stimulus correlated discharge periodicities of single neurons described in the literature for all parts of the acoustic channel below the geniculatum mediale were confirmed for the colliculus inferior. Furthermore a quite different kind of discharge periodicity in the geniculatum mediale is reported. With these results structure models are given for the neuronal temporal measurement of coincidence. Finally a possibility of discrimination between intra-modality-specific and intra-modality-nonspecific processing mechanism is shown. © 1969 Springer-Verlag.