[Purely phasic neurons of the medial geniculate body--markers of changes in the signal].

The majority of neurons in the medial geniculate body responded with short bursts of activity to increments of the noise signal, and some of them--to decrements of the signal as well. Responses to changes in the signal envelope were only observed in narrow intensity range different for different neurons. The data suggest that division of neurons into groups acting within local dynamic ranges related to the cochlear nerve level, remains on the medial geniculate body level so as the ability of the organism to detect small changes in the signal envelope is maintained by the convergence of information from local detectors.