RT Journal Article
SR Electronic
T1 Patterns of unit activity in the rostral thalamus of cats related to short-latency discrimination between different auditory stimuli
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 48
OP 58
DO 10.1523/JNEUROSCI.11-01-00048.1991
VO 11
IS 1
A1 CD Woody
A1 E Gruen
A1 O Melamed
A1 V Chizhevsky
YR 1991
UL http://www.jneurosci.org/content/11/1/48.abstract
AB Short-latency auditory-responsive units were found in the rostral thalamus of cats during performance of conditioned eyeblink responses (CRs) elicited discriminatively by a forward-paired, 70-dB-click conditioned stimulus (CS) as opposed to a backward-paired, 70-dB-hiss discriminative stimulus (DS). Discharges in response to the CS or DS were found in 57% of 138 units tested. Forty-one percent of units responding to the CS did so at latencies of less than 40 msec. After conditioning a discriminative CR to click CS, an increase in the ratio of CS-evoked activity to baseline activity was found relative to that before conditioning. This increase was attributable, in part, to a decrease in baseline activity and, in part, to an increase in the magnitude of response to the CS. These responses preceded early components of the electromyographically measured motor responses with latencies sufficient to contribute to initiation of the movement. After acquisition of the CR, the proportion of CS responsive units also increased. We conclude that this area of the thalamus, a region thought to support thalamocortical reverberatory activity, also functions to transmit short-latency auditory signals. Our evidence further suggests that this region may participate in the elicitation of conditioned responses by specific auditory stimuli and in discrimination between auditory stimuli of different significance.