Sigita Augustinaite, Two-photon imaging of the deepest cortical layer in the behaving mouse

Speaker: Sigita Augustinaite, Optical Neuroimaging (Kuhn) Unit

Title: Two-photon imaging of the deepest cortical layer in the behaving mouse

Abstract: Our sensory organs (eyes, ears, tongue, skin and nose) connect the outside world to our inner world, modeled in the brain. The accuracy and intensity of what we feel, depends not only on the physical properties of the sensory stimuli (e.g. brightness of a lightning or decibels of a thunder), but also on our behavioral state (e.g. are we alert or sleeping during the thunderstorm). Layer 6 (L6), the deepest lamina of cerebral cortex, is part of the thalamocortical circuit and so, one of the key structures regulating behavior state related processing of sensory information. However, very little is known about L6 neuronal activity in vivo, especially in awake animal. Here, we focus on primary visual cortex L6 feedback projections to visual thalamus (dorsal lateral geniculate nucleus) which regulate visual signal transmission from retina to cortex. To study corticothalamic feedback in response to visual stimulation during different behavior states, we image calcium activity of L6 neurons with two-photon microscopy for hours in head-fixed mice. Simultaneously, we record and determine the behavioral state by electrocorticogram, pupil size and locomotion. In this seminar, I will explain how the thalamocortical circuit is involved in state-dependent sensory input transfer, describe principal experimental procedures and discuss our main findings. Looking forward to see you!

After the seminar (17:00-17:30), join us for discussion with free pizza and soft drinks!