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English

Retinal waves drive the activity-dependent development of visual circuits in vivo
Michael Crair (Yale University School of Medicine)

日時

September 24, 2012 (Mon), 17:00-18:00

場所

3F Seminar Room, Nanobiology Building

演者

Michael Crair (Yale University School of Medicine)

演題

Retinal waves drive the activity-dependent development of visual circuits in vivo

要旨

The display of patterned spontaneous activity is an emergent property of the immature nervous system that is thought to mediate synaptic competition and instruct self-organization in many developing neural circuits. In the visual system, isolated (in vitro) preparations of developing retina exhibit propagating electrical activity amongst neighboring retinal ganglion cells (RGCs), termed 'retinal waves'. Since RGCs relay visual information to higher order structures in the central nervous system, retinal waves are thought to play a key role in activity-dependent refinement of topographic neural maps in the superior colliculus (SC), lateral geniculate nucleus (LGN), and visual cortex (VCtx). However, the role of retinal waves in neural circuit development remains remarkably controversial, in part because their existence has never been demonstrated in vivo, likely because of the methodological challenges associated with recording from a large cohort of RGCs in neonatal animals. We describe experiments using a highly novel imaging approach to examine and characterize spontaneous activity throughout the visual neuraxis in neonatal mice in vivo. We show that traveling waves of spontaneous activity occur in awake, behaving neonatal mice, and examine the spatiotemporal properties of waves throughout the developing visual system during the first two weeks after birth. Our data indicate that spontaneous retinal waves in vivo exhibit a similar profile as those described previously in vitro. Moreover, retinal waves generate matched activity patterns in the SC and VCtx. We also show that exogenously manipulating the pattern of activity during the first week after birth alters the neural circuit that forms in the developing visual system. Given the remarkable fidelity of retinal waves during the period prior to eye opening in mice we report here in vivo, together with previous work demonstrating that spontaneous waves within macaque retina are present in vitro before birth, the visual system likely experiences patterned activation by retinal waves for a substantial gestational period during human fetal development that may be crucial for shaping the functional maturation of neural circuits before the onset of sensory experience.

世話人

Nobuhiko Yamamoto
Tel: 06-6879-4636
E-mail: nobuhiko[at]fbs.osaka-u.ac.jp


http://www.fbs.osaka-u.ac.jp/jpn/seminar/seminar/docs/fbs-seminar-yamamoto-20120924-b.pdf