Elsevier

Neuroscience Letters

Volume 358, Issue 1, 18 March 2004, Pages 49-52
Neuroscience Letters

The dual pattern of corticothalamic projection of the primary auditory cortex in macaque monkey

https://doi.org/10.1016/j.neulet.2004.01.008Get rights and content

Abstract

The distribution and terminal morphology of the corticothalamic projection originating from the primary auditory cortex (A1) were established in a macaque monkey, using the anterograde (and retrograde) tracer biotinylated dextran amine. A dense corticothalamic projection from A1 was found in the ventral (vMGB) and dorsal (dMGB) divisions of the medial geniculate body and, to a lesser extent, in the medial division (mMGB), the posterior thalamic nucleus (PO) and the suprageniculate nucleus. Most terminal boutons were small (<1 μm), except some large boutons (2–6 μm) located in PO and vMGB. The data demonstrate that the corticothalamic projection from A1 in primate consists of two types of terminals (small and giant endings) in line with previous observations in rat and cat. Retrogradely labeled thalamocortical neurons formed clusters generally overlapping the corticothalamic terminal fields.

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Acknowledgements

We thank V. Moret, C. Roulin, and F. Tinguely for their technical assistance for histology, J. Corpataux and B. Morandi for animal care and surgical assistance, A. Gaillard and B. Aebischer for mechanics and electronics, L. Monney for computer sciences. Grant Sponsors: Swiss National Science Foundation, grants No 31-43422.95 and 31-61857.00, National Center of Competence in Research (NCCR) in Neurosciences.

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