a visual pathway links brain structures active during magnetic compass orientation in migratory birds视觉通路连接大脑结构活跃在候鸟磁罗经方位.pdfVIP

A Visual Pathway Links Brain Structures Active during Magnetic Compass Orientation in Migratory Birds 1 2 3 ¨ ¨ ¨ 2 1 Dominik Heyers *, Martina Manns , Harald Luksch , Onur Gunturkun , Henrik Mouritsen 1 AG Neurosensorik, Institute of Biology, University of Oldenburg, Oldenburg, Germany, 2 Department of Biopsychology, Institute for Cognitive Neuroscience, Ruhr-University Bochum, Bochum, Germany, 3 Chair of Zoology, Department of Zoology, Technical University Munich, Freising- Weihenstephan, Germany The magnetic compass of migratory birds has been suggested to be light-dependent. Retinal cryptochrome-expressing neurons and a forebrain region, ‘‘Cluster N’’, show high neuronal activity when night-migratory songbirds perform magnetic compass orientation. By combining neuronal tracing with behavioral experiments leading to sensory-driven gene expression of the neuronal activity marker ZENK during magnetic compass orientation, we demonstrate a functional neuronal connection between the retinal neurons and Cluster N via the visual thalamus. Thus, the two areas of the central nervous system being most active during magnetic compass orientation are part of an ascending visual processing stream, the thalamofugal pathway. Furthermore, Cluster N seems to be a specialized part of the visual wulst. These findings strongly support the hypothesis that migratory birds use their visual system to perceive the reference compass direction of the geomagnetic field and that migratory birds ‘‘see’’ the reference compass direction provided by the geomagnetic field. ¨ ¨ ¨ Citation: Heyers D, Manns M, Luksch H, Gunturkun O, Mouritsen H (2007) A Visual Pathway Links Brain Structures Active during