Night-migratory songbirds travel thousands of kilometers between breeding and wintering grounds, relying on celestial cues and the Earth’s magnetic field for navigation. Both visual and—presumably—magnetic information are processed at the level of the retina. Despite growing interest in avian magnetoreception, the cellular and circuit-level organization of the bird retina remains poorly understood.
In this seminar, Professor Karin Dedek will present recent work dissecting the retinal circuitry of songbirds using a combination of immunohistochemistry, serial electron microscopy reconstructions, and adeno-associated virus (AAV)–mediated EGFP expression. She will discuss distinct adaptations of the bird retina, including the remarkable anoxia tolerance of the inner retina and the organization of the avian double-cone photoreceptor system, composed of a principal and an accessory member (recently termed PR5 and PR6).
Special attention will be given to the retinal distribution of double cones and their synaptic connectivity with bipolar and horizontal cells. These findings allow new hypotheses about horizontal cell light responses and point toward a potential retinal pathway involved in magnetoreception. Together, this work provides novel insights into how visual and magnetic signals may be integrated at the earliest stages of sensory processing.
This research was supported by the DFG-funded Collaborative Research Center SFB 1372 “Magnetoreception and Navigation in Vertebrates”.
About the speaker
Prof. Karin Dedek is an Adjunct Professor at the University of Oldenburg and a long-standing investigator in sensory neuroscience, with a particular focus on retinal processing of visual and magnetic signals in mice and birds. She earned her PhD studying potassium ion channels in the laboratory of Prof. Dr. Thomas Jentsch in Hamburg, where she performed electrophysiological recordings from cochlear hair cells in mice.
During her postdoctoral work at the University of Oldenburg and Weill Medical College of Cornell University in New York, she investigated the functional role of gap junctions in the mouse retina, further strengthening her expertise in retinal circuitry and signal integration. She has been an Adjunct Professor at the University of Oldenburg since 2015 and has served as principal investigator in numerous European and national collaborative research projects.
Currently, Karin is a principal investigator and board member of the Cluster of Excellence “NaviSense” and the Collaborative Research Center 1372 “Magnetoreception and Navigation in Vertebrates”. She was included in the TOP LIST of Excellent Women in European Vision Research and Ophthalmology (2021) and has served as Reviewing Editor for The Journal of Physiology since 2022.
