Details

Autor(en) / Beteiligte

• Niederleitner, Bertram
• Gutierrez‐Ibanez, Cristian
• Krabichler, Quirin
• Weigel, Stefan
• Luksch, Harald

Titel

A novel relay nucleus between the inferior colliculus and the optic tectum in the chicken (Gallus gallus)

Ist Teil von

• Journal of comparative neurology (1911), 2017-02, Vol.525 (3), p.513-534

Ort / Verlag

United States: Wiley Subscription Services, Inc

Erscheinungsjahr

2017

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• ABSTRACT Processing multimodal sensory information is vital for behaving animals in many contexts. The barn owl, an auditory specialist, is a classic model for studying multisensory integration. In the barn owl, spatial auditory information is conveyed to the optic tectum (TeO) by a direct projection from the external nucleus of the inferior colliculus (ICX). In contrast, evidence of an integration of visual and auditory information in auditory generalist avian species is completely lacking. In particular, it is not known whether in auditory generalist species the ICX projects to the TeO at all. Here we use various retrograde and anterograde tracing techniques both in vivo and in vitro, intracellular fillings of neurons in vitro, and whole‐cell patch recordings to characterize the connectivity between ICX and TeO in the chicken. We found that there is a direct projection from ICX to the TeO in the chicken, although this is small and only to the deeper layers (layers 13–15) of the TeO. However, we found a relay area interposed among the IC, the TeO, and the isthmic complex that receives strong synaptic input from the ICX and projects broadly upon the intermediate and deep layers of the TeO. This area is an external portion of the formatio reticularis lateralis (FRLx). In addition to the projection to the TeO, cells in FRLx send, via collaterals, descending projections through tectopontine‐tectoreticular pathways. This newly described connection from the inferior colliculus to the TeO provides a solid basis for visual‐auditory integration in an auditory generalist bird. J. Comp. Neurol. 525:513–534, 2017. © 2016 Wiley Periodicals, Inc. We used various methods to characterize the connectivity between the external nucleus of the inferior colliculus (ICX) and the optic tectum (TeO) in the chicken. Although we found only a small reciprocal connection between ICX and the TeO, we found that the external portion of the formatio reticularis lateralis receives inputs from ICX and projects to the TeO.