Role of the medial geniculate body in the production of conditioned reflexes to amplitude-modulated stimuli in rats

1.	The limiting frequency of modulation of the amplitude of the stimulus at which differentiation between tonal and amplitude-modulated stimuli is still possible, detectable after bilateral ablation of the auditory cortex of the rat brain, does not change following bisection of the brachia of the posterior colliculus.
2.	Bilateral ablation of the auditory cortex and section of the brachia of the posterior colliculus in rats completely impair differentiation between the tonal stimulus and the amplitude-modulated signals with a modulation frequency below 27–31 Hz, and have no effect on the differentiation between tonal and amplitude-modulated signals with modulation frequencies above 27–31 Hz.

Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 37, No. 2, pp. 265–271, March–April, 1987.