Kalmykova I V
Zh Vyssh Nerv Deiat Im I P Pavlova. 1990 May-Jun;40(3):451-5.
Cats were trained to discriminate stimuli linearly modulated in frequency. Discrimination threshold were measured with limit method. The differential threshold, delta F/F0.100%, turned out to be constant and equal to be about 3% in the range of 1.5-6.5 kHz with no dependence on both temporal structure and frequency variation rate.