Lm. Kitzes et Gs. Hollrigel, RESPONSE PROPERTIES OF UNITS IN THE POSTERIOR AUDITORY FIELD DEPRIVEDOF INPUT FROM THE IPSILATERAL PRIMARY AUDITORY-CORTEX, Hearing research, 100(1-2), 1996, pp. 120-130
The influence of the ipsilateral primary auditory field (AI) on the re
sponse properties of neurons in the posterior auditory field (Field P)
was examined in three cats anesthetized with sodium pentobarbital. Ra
te/level functions were obtained, by extracellular recording, from sin
gle units in Field P before (n=38) and after (n=50) subpial aspiration
of AI. The ablations were primarily confined to the medial ectosylvia
n gyrus, although in one case extended into the high-frequency portion
of the anterior auditory field. Comparisons between the behavior of u
nits isolated before and after AI ablation failed to demonstrate any c
hanges in the response properties of neurons in Field P attributable t
o the ablation. Nonmonotonic response profiles, first spike latency, v
ariability in latency, threshold and maximal discharge rates of the un
its to acoustic stimuli were not significantly altered by the AI ablat
ion. These results indicate that the basic response properties of neur
ons in Field P do not depend on input from the ipsilateral AI. This su
ggests that these properties are most likely determined by thalamic in
put or by circuitry within Field P.