Medial Geniculate, Amygdalar and Cingulate Cortical Training-Induced Neuronal Activity during Discriminative Avoidance Learning in Rabbits with Auditory Cortical Lesions

Title
Medial Geniculate, Amygdalar and Cingulate Cortical Training-Induced Neuronal Activity during Discriminative Avoidance Learning in Rabbits with Auditory Cortical Lesions
Publication Date
2001
Author(s)
Duvel, AD
Smith, DM
Talk, A
( author )
OrcID: https://orcid.org/0000-0002-3449-5756
Email: atalk@une.edu.au
UNE Id une-id:atalk
Gabriel, M
Type of document
Journal Article
Language
en
Entity Type
Publication
Publisher
Society for Neuroscience
Place of publication
United States of America
UNE publication id
une:418
Abstract
This study addressed the neural mediation of discriminative avoidance learning, wherein rabbits step in a wheel apparatus in response to an acoustic conditional stimulus, the CS+, to avoid a foot shock, and they learn to ignore a different stimulus, the CS, not followed by foot shock. Previously, muscimol-induced inactivation of the amygdalar in the first session of training prevented learning during the inactivation and permanently blocked the development of discriminative training-induced neuronal activity (TIA) in the medial division of the medial geniculate nucleus (MGm). These results suggested that amygdalar neurons induce discriminative TIA in the MGm via basolateral (BL) amygdalar axonal projections to the auditory cortex. To test this hypothesis, the activity of neurons in the MGm was recorded during learning in rabbits with lesions of the auditory cortex. Recordings were also made in the lateral and BL amygdalar nuclei and in the cingulate cortex. In support of the hypothesis, discriminative learning in rabbits with lesions was impaired significantly during early training sessions 1-4; in these same sessions, discriminative TIA was abolished in the MGm, the BL nucleus, and the anterior cingulate cortex. The lesions also blocked posterior cingulate cortical discriminative TIA in training sessions 1-2 but spared TIA in sessions 3-7. Lateral amygdalar neurons showed gradual development of discrimination that was not significantly affected by the lesions. The results demonstrate a critical role of auditory cortex in early discriminative learning and in the production of early discriminative TIA in multiple areas.
Link
Citation
The Journal of Neuroscience, 21(9), p. 3271-3281
ISSN
1529-2401
0270-6474
Start page
3271
End page
3281

Files:

NameSizeformatDescriptionLink